Чудаков Дмитрий Михайлович

Личная информация

Окончил Московский Государственный Университет им. М. В. Ломоносова. Работает в ИБХ РАН с 2000 года. Защитил кандидатскую (2003 год) и докторскую (2011 год) диссертации по разработке и применению генетически кодируемых флуоресцентных инструментов. С 2011 года возглавляет лабораторию Геномики адаптивного иммунитета ИБХ РАН.

 

Образование

Период обученияСтрана, городУчебное заведениеДополнительная информация
1995–2000 Россия, Москва МГУ им. Ломоносова

Премии и заслуги

1. Медаль Российской академии наук с премией для молодых ученых РАН, 2005 г.

2. Медаль Европейской Академии наук, 2006 г.

3. Лауреат программы "Выдающиеся ученые. Кандидаты и доктора наук РАН", 2006-2007, 2008-2009 гг.

4. Диплом I степени МАИК за лучшую публикацию в журнале «Биоорганическая химия» за 2008 год.

5. Премия  конкурса МАИК «Наука/Интерпериодика» на лучшую публикацию по биологическим наукам за 2008 год.

6. Диплом за лучшую публикацию в журналах РАН за 2008 год.

7. Диплом II степени МАИК за лучшую публикацию в журнале «Биоорганическая химия» за 2011 год.

8.Диплом за лучшую публикацию в журналах РАН за 2011год.

9. Диплом за наиболее цитируемую за 2011 год публикацию в журналах группы BJ Cell.

10. Премия Президента Российской Федерации для молодых ученых в области науки и инноваций за 2012 год

 

Основные научные результаты

Расшифровал механизм обратимой фотоактивации флуоресценции, подразумевающий цис-транс изомеризацию хромофора, и получил целый ряд так называемых фотоактивируемых белков с высоким контрастом активации. Флуоресцентные характеристики таких белков могут обратимо либо необратимо изменяться в ответ на облучение светом определенной длины волны, что предоставляет уникальные возможности для прицельной маркировки и слежения за живыми объектами, а также для технологий флуоресцентной микроскопии сверх-высокого разрешения.

Разработал палитру ярких мономерных флуоресцентных белков, флуоресцирующих в диапазоне всего видимого спектра и позволяющих проводить многоцветное мечение молекул в живых клетках: TagBFP, TagCFP, TagGFP, TagYFP, TagRFP, а также дальне-красные белки mKate и mKate2. Белок TagRFP является самым ярким из разработанных мономерных красных флуоресцентных белков, существенно опережая немногие имеющиеся аналоги, и хорошо зарекомендовал себя в химерных конструкциях с различными исследуемыми белками. Белок mKate2 является абсолютным лидером по яркости среди мономерных дальне-красных флуоресцентных белков.

Разработал яркие быстро созревающие белки: TurboGFP, TurboYFP, TurboRFP, TurboFP602, а также яркий дальне-красный белок Катюша (Katushka, TurboFP635). Уникальное для флуоресцентных белков сочетание высокой яркости и длинноволнового излучения позволяет эффективно детектировать сигнал Катюши в живых тканях, проницаемость которых повышена в дальне-красной области спектра. Катюша существенно повышает чувствительность технологий прижизненной визуализации клеток и тканей в интактных трансгенных организмах, и в перспективе может найти свое применение в практической медицине.

Получил ряд высоко-контрастных генетически кодируемых сенсоров на основе флуоресцентных белков, в том числе сенсоров концентрации кальция, сенсоров программируемой клеточной гибели.

С участием Чудакова Д. М. получен первый и единственный на сегодняшний день генетически кодируемый фотосенсибилизатор KillerRed.

Разработанные Чудаковым Д. М. флуоресцентные инструменты широко используются в научных лабораториях и на фармацевтических компаниях. Чудаков Д. М. является автором более 60 статей в рецензируемых журналах. Индивидуальный индекс цитирования: 3900. Индекс Хирша: 28.

Чудаков Д. М. принимал участие более чем в 40 международных конференциях, в большинстве случаев в качестве докладчика.

Чудаков Д. М. является соавтором ряда патентов и  международных патентных заявок.

Под руководством Чудакова Д.М. были защищены кандидатские диссертации:

Суслова Екатерина Андреевна, «Высококонтрастные генетически кодируемые сенсоры на основе зеленого флуоресцентного белка», 2008 год, по специальности  «Молекулярная биология».

Щербо Дмитрий Сергеевич, «Дальнекрасные флуоресцентные белки», 2010 год, по специальности  «Молекулярная биология».

Путинцева Екатерина Викторовна, "Разнообразие репертуаров Т-клеточных рецепторов человека и его изменения в ходе старения", 2014 год, по специальности  «Молекулярная биология».

 

Избранные публикации

  1. Turchaninova M.A., Davydov A., Britanova O.V., Shugay M., Bikos V., Egorov E.S., Kirgizova V.I., Merzlyak E.M., Staroverov D.B., Bolotin D.A., Mamedov I.Z., Izraelson M., Logacheva M.D., Kladova O., Plevova K., Pospisilova S., Chudakov D.M. (2016). High-quality full-length immunoglobulin profiling with unique molecular barcoding. Nat Protoc 11 (9), 1599–616 [+]

    High-throughput sequencing analysis of hypermutating immunoglobulin (IG) repertoires remains a challenging task. Here we present a robust protocol for the full-length profiling of human and mouse IG repertoires. This protocol uses unique molecular identifiers (UMIs) introduced in the course of cDNA synthesis to control bottlenecks and to eliminate PCR and sequencing errors. Using asymmetric 400+100-nt paired-end Illumina sequencing and UMI-based assembly with the new version of the MIGEC software, the protocol allows up to 750-nt lengths to be sequenced in an almost error-free manner. This sequencing approach should also be applicable to various tasks beyond immune repertoire studies. In IG profiling, the achieved length of high-quality sequence covers the variable region of even the longest chains, along with the fragment of a constant region carrying information on the antibody isotype. The whole protocol, including preparation of cells and libraries, sequencing and data analysis, takes 5 to 6 d.

    ID:1665
  2. Britanova O.V., Shugay M., Merzlyak E.M., Staroverov D.B., Putintseva E.V., Turchaninova M.A., Mamedov I.Z., Pogorelyy M.V., Bolotin D.A., Izraelson M., Davydov A.N., Egorov E.S., Kasatskaya S.A., Rebrikov D.V., Lukyanov S., Chudakov D.M. (2016). Dynamics of Individual T Cell Repertoires: From Cord Blood to Centenarians. J. Immunol. 196 (12), 5005–13 [+]

    The diversity, architecture, and dynamics of the TCR repertoire largely determine our ability to effectively withstand infections and malignancies with minimal mistargeting of immune responses. In this study, we have employed deep TCRβ repertoire sequencing with normalization based on unique molecular identifiers to explore the long-term dynamics of T cell immunity. We demonstrate remarkable stability of repertoire, where approximately half of all T cells in peripheral blood are represented by clones that persist and generally preserve their frequencies for 3 y. We further characterize the extremes of lifelong TCR repertoire evolution, analyzing samples ranging from umbilical cord blood to centenarian peripheral blood. We show that the fetal TCR repertoire, albeit structurally maintained within regulated borders due to the lower numbers of randomly added nucleotides, is not limited with respect to observed functional diversity. We reveal decreased efficiency of nonsense-mediated mRNA decay in umbilical cord blood, which may reflect specific regulatory mechanisms in development. Furthermore, we demonstrate that human TCR repertoires are functionally more similar at birth but diverge during life, and we track the lifelong behavior of CMV- and EBV-specific T cell clonotypes. Finally, we reveal gender differences in dynamics of TCR diversity constriction, which come to naught in the oldest age. Based on our data, we propose a more general explanation for the previous observations on the relationships between longevity and immunity.

    ID:1534
  3. Nazarov V.I., Minervina A.A., Komkov A.Y., Pogorelyy M.V., Maschan M.A., Olshanskaya Y.V., Zvyagin I.V., Chudakov D.M., Lebedev Y.B., Mamedov I.Z. (2016). Reliability of immune receptor rearrangements as genetic markers for minimal residual disease monitoring. Bone marrow transplantation , ID:1532
  4. Sarkisyan K.S., Bolotin D.A., Meer M.V., Usmanova D.R., Mishin A.S., Sharonov G.V., Ivankov D.N., Bozhanova N.G., Baranov M.S., Soylemez O., Bogatyreva N.S., Vlasov P.K., Egorov E.S., Logacheva M.D., Kondrashov A.S., Chudakov D.M., Putintseva E.V., Mamedov I.Z., Tawfik D.S., Lukyanov K.A., Kondrashov F.A. (2016). Local fitness landscape of the green fluorescent protein. Nature 533 (7603), 397–401 [+]

    Fitness landscapes depict how genotypes manifest at the phenotypic level and form the basis of our understanding of many areas of biology, yet their properties remain elusive. Previous studies have analysed specific genes, often using their function as a proxy for fitness, experimentally assessing the effect on function of single mutations and their combinations in a specific sequence or in different sequences. However, systematic high-throughput studies of the local fitness landscape of an entire protein have not yet been reported. Here we visualize an extensive region of the local fitness landscape of the green fluorescent protein from Aequorea victoria (avGFP) by measuring the native function (fluorescence) of tens of thousands of derivative genotypes of avGFP. We show that the fitness landscape of avGFP is narrow, with 3/4 of the derivatives with a single mutation showing reduced fluorescence and half of the derivatives with four mutations being completely non-fluorescent. The narrowness is enhanced by epistasis, which was detected in up to 30% of genotypes with multiple mutations and mostly occurred through the cumulative effect of slightly deleterious mutations causing a threshold-like decrease in protein stability and a concomitant loss of fluorescence. A model of orthologous sequence divergence spanning hundreds of millions of years predicted the extent of epistasis in our data, indicating congruence between the fitness landscape properties at the local and global scales. The characterization of the local fitness landscape of avGFP has important implications for several fields including molecular evolution, population genetics and protein design.

    ID:1529
  5. Bagaev D.V., Zvyagin I.V., Putintseva E.V., Izraelson M., Britanova O.V., Chudakov D.M., Shugay M. (2016). VDJviz: a versatile browser for immunogenomics data. BMC Genomics 17 (1), 453 [+]

    The repertoire of T- and B-cell receptor sequences encodes the antigen specificity of adaptive immunity system, determines its present state and guides its ability to mount effective response against encountered antigens in future. High throughput sequencing of immune repertoires (Rep-Seq) is a promising technique that allows to profile millions of antigen receptors of an individual in a single experiment. While a substantial number of tools for mapping and assembling Rep-Seq data were published recently, the field still lacks an intuitive and flexible tool that can be used by researchers with little or no computational background for in-depth analysis of immune repertoire profiles.

    ID:1531
  6. Feng Y., vanderVeeken J., Shugay M., Putintseva E.V., Osmanbeyoglu H.U., Dikiy S., Hoyos B.E., Moltedo B., Hemmers S., Treuting P., Leslie C.S., Chudakov D.M., Rudensky A.Y. (2015). A mechanism for expansion of regulatory T-cell repertoire and its role in self-tolerance. Nature 528 (7580), 132–6 [+]

    T-cell receptor (TCR) signalling has a key role in determining T-cell fate. Precursor cells expressing TCRs within a certain low-affinity range for complexes of self-peptide and major histocompatibility complex (MHC) undergo positive selection and differentiate into naive T cells expressing a highly diverse self-MHC-restricted TCR repertoire. In contrast, precursors displaying TCRs with a high affinity for 'self' are either eliminated through TCR-agonist-induced apoptosis (negative selection) or restrained by regulatory T (Treg) cells, whose differentiation and function are controlled by the X-chromosome-encoded transcription factor Foxp3 (reviewed in ref. 2). Foxp3 is expressed in a fraction of self-reactive T cells that escape negative selection in response to agonist-driven TCR signals combined with interleukin 2 (IL-2) receptor signalling. In addition to Treg cells, TCR-agonist-driven selection results in the generation of several other specialized T-cell lineages such as natural killer T cells and innate mucosal-associated invariant T cells. Although the latter exhibit a restricted TCR repertoire, Treg cells display a highly diverse collection of TCRs. Here we explore in mice whether a specialized mechanism enables agonist-driven selection of Treg cells with a diverse TCR repertoire, and the importance this holds for self-tolerance. We show that the intronic Foxp3 enhancer conserved noncoding sequence 3 (CNS3) acts as an epigenetic switch that confers a poised state to the Foxp3 promoter in precursor cells to make Treg cell lineage commitment responsive to a broad range of TCR stimuli, particularly to suboptimal ones. CNS3-dependent expansion of the TCR repertoire enables Treg cells to control self-reactive T cells effectively, especially when thymic negative selection is genetically impaired. Our findings highlight the complementary roles of these two main mechanisms of self-tolerance.

    ID:1533
  7. Egorov E.S., Merzlyak E.M., Shelenkov A.A., Britanova O.V., Sharonov G.V., Staroverov D.B., Bolotin D.A., Davydov A.N., Barsova E., Lebedev Y.B., Shugay M., Chudakov D.M. (2015). Quantitative profiling of immune repertoires for minor lymphocyte counts using unique molecular identifiers. J. Immunol. 194 (12), 6155–63 [+]

    Emerging high-throughput sequencing methods for the analyses of complex structure of TCR and BCR repertoires give a powerful impulse to adaptive immunity studies. However, there are still essential technical obstacles for performing a truly quantitative analysis. Specifically, it remains challenging to obtain comprehensive information on the clonal composition of small lymphocyte populations, such as Ag-specific, functional, or tissue-resident cell subsets isolated by sorting, microdissection, or fine needle aspirates. In this study, we report a robust approach based on unique molecular identifiers that allows profiling Ag receptors for several hundred to thousand lymphocytes while preserving qualitative and quantitative information on clonal composition of the sample. We also describe several general features regarding the data analysis with unique molecular identifiers that are critical for accurate counting of starting molecules in high-throughput sequencing applications.

    ID:1313
  8. Bolotin D.A., Poslavsky S., Mitrophanov I., Shugay M., Mamedov I.Z., Putintseva E.V., Chudakov D.M. (2015). MiXCR: software for comprehensive adaptive immunity profiling. Nat. Methods 12 (5), 380–1 ID:1270
  9. Shugay M., Britanova O.V., Merzlyak E.M., Turchaninova M.A., Mamedov I.Z., Tuganbaev T.R., Bolotin D.A., Staroverov D.B., Putintseva E.V., Plevova K., Linnemann C., Shagin D., Pospisilova S., Lukyanov S., Schumacher T.N., Chudakov D.M. (2014). Towards error-free profiling of immune repertoires. Nat. Methods 11 (6), 653–5 [+]

    Deep profiling of antibody and T cell-receptor repertoires by means of high-throughput sequencing has become an attractive approach for adaptive immunity studies, but its power is substantially compromised by the accumulation of PCR and sequencing errors. Here we report MIGEC (molecular identifier groups-based error correction), a strategy for high-throughput sequencing data analysis. MIGEC allows for nearly absolute error correction while fully preserving the natural diversity of complex immune repertoires.

    ID:1163
  10. Zvyagin I.V., Pogorelyy M.V., Ivanova M.E., Komech E.A., Shugay M., Bolotin D.A., Shelenkov A.A., Kurnosov A.A., Staroverov D.B., Chudakov D.M., Lebedev Y.B., Mamedov I.Z. (2014). Distinctive properties of identical twins' TCR repertoires revealed by high-throughput sequencing. Proc. Natl. Acad. Sci. U.S.A. , [+]

    Adaptive immunity in humans is provided by hypervariable Ig-like molecules on the surface of B and T cells. The final set of these molecules in each organism is formed under the influence of two forces: individual genetic traits and the environment, which includes the diverse spectra of alien and self-antigens. Here we assess the impact of individual genetic factors on the formation of the adaptive immunity by analyzing the T-cell receptor (TCR) repertoires of three pairs of monozygous twins by next-generation sequencing. Surprisingly, we found that an overlap between the TCR repertoires of monozygous twins is similar to an overlap between the TCR repertoires of nonrelated individuals. However, the number of identical complementary determining region 3 sequences in two individuals is significantly increased for twin pairs in the fraction of highly abundant TCR molecules, which is enriched by the antigen-experienced T cells. We found that the initial recruitment of particular TCR V genes for recombination and subsequent selection in the thymus is strictly determined by individual genetic factors. J genes of TCRs are selected randomly for recombination; however, the subsequent selection in the thymus gives preference to some α but not β J segments. These findings provide a deeper insight into the mechanism of TCR repertoire generation.

    ID:1015
  11. Britanova O.V., Putintseva E.V., Shugay M., Merzlyak E.M., Turchaninova M.A., Staroverov D.B., Bolotin D.A., Lukyanov S., Bogdanova E.A., Mamedov I.Z., Lebedev Y.B., Chudakov D.M. (2014). Age-Related Decrease in TCR Repertoire Diversity Measured with Deep and Normalized Sequence Profiling. J. Immunol. 192 (6), 2689–98 [+]

    The decrease of TCR diversity with aging has never been studied by direct methods. In this study, we combined high-throughput Illumina sequencing with unique cDNA molecular identifier technology to achieve deep and precisely normalized profiling of TCR β repertoires in 39 healthy donors aged 6-90 y. We demonstrate that TCR β diversity per 10(6) T cells decreases roughly linearly with age, with significant reduction already apparent by age 40. The percentage of naive T cells showed a strong correlation with measured TCR diversity and decreased linearly up to age 70. Remarkably, the oldest group (average age 82 y) was characterized by a higher percentage of naive CD4(+) T cells, lower abundance of expanded clones, and increased TCR diversity compared with the previous age group (average age 62 y), suggesting the influence of age selection and association of these three related parameters with longevity. Interestingly, cross-analysis of individual TCR β repertoires revealed a set >10,000 of the most representative public TCR β clonotypes, whose abundance among the top 100,000 clones correlated with TCR diversity and decreased with aging.

    ID:1010
  12. Linnemann C., Heemskerk B., Kvistborg P., Kluin R.J., Bolotin D.A., Chen X., Bresser K., Nieuwland M., Schotte R., Michels S., GomezEerland R., Jahn L., Hombrink P., Legrand N., Shu C.J., Mamedov I.Z., Velds A., Blank C.U., Haanen J.B., Turchaninova M.A., Kerkhoven R.M., Spits H., Hadrup S.R., Heemskerk M.H., Blankenstein T., Chudakov D.M., Bendle G.M., Schumacher T.N. (2013). High-throughput identification of antigen-specific TCRs by TCR gene capture. Nat. Med. , [+]

    The transfer of T cell receptor (TCR) genes into patient T cells is a promising approach for the treatment of both viral infections and cancer. Although efficient methods exist to identify antibodies for the treatment of these diseases, comparable strategies to identify TCRs have been lacking. We have developed a high-throughput DNA-based strategy to identify TCR sequences by the capture and sequencing of genomic DNA fragments encoding the TCR genes. We establish the value of this approach by assembling a large library of cancer germline tumor antigen-reactive TCRs. Furthermore, by exploiting the quantitative nature of TCR gene capture, we show the feasibility of identifying antigen-specific TCRs in oligoclonal T cell populations from either human material or TCR-humanized mice. Finally, we demonstrate the ability to identify tumor-reactive TCRs within intratumoral T cell subsets without knowledge of antigen specificities, which may be the first step toward the development of autologous TCR gene therapy to target patient-specific neoantigens in human cancer.

    ID:885
  13. Bolotin D.A., Shugay M., Mamedov I.Z., Putintseva E.V., Turchaninova M.A., Zvyagin I.V., Britanova O.V., Chudakov D.M. (2013). MiTCR: software for T-cell receptor sequencing data analysis. Nat. Methods 10 (9), 813–4 ID:886
  14. Pletnev V.Z., Pletneva N.V., Lukyanov K.A., Souslova E.A., Fradkov A.F., Chudakov D.M., Chepurnykh T., Yampolsky I.V., Wlodawer A., Dauter Z., Pletnev S. (2013). Structure of the red fluorescent protein from a lancelet (Branchiostoma lanceolatum): a novel GYG chromophore covalently bound to a nearby tyrosine. Acta Crystallogr. D Biol. Crystallogr. 69 (Pt 9), 1850–60 [+]
    ID:1017
  15. Turchaninova M.A., Britanova O.V., Bolotin D.A., Shugay M., Putintseva E.V., Staroverov D.B., Sharonov G., Shcherbo D., Zvyagin I.V., Mamedov I.Z., Linnemann C., Schumacher T.N., Chudakov D.M. (2013). Pairing of T-cell receptor chains via emulsion PCR. European journal of immunology , [+]

    Our ability to analyze adaptive immunity and engineer its activity has long been constrained by our limited ability to identify native pairs of heavy-light antibody chains and alpha-beta T-cell receptor (TCR) chains - both of which comprise coupled "halves of a key", collectively capable of recognizing specific antigens. Here we report a cell-based emulsion RT-PCR approach that allows the selective fusion of the native pairs of amplified TCR alpha and beta chain genes for complex samples. A new type of PCR suppression technique was developed that makes it possible to amplify the fused library with minimal noise for subsequent analysis by high-throughput paired-end Illumina sequencing. With this technique, single analysis of a complex blood sample allows identification of multiple native TCR chain pairs. This approach may be extended to identify native antibody chain pairs and, more generally, pairs of mRNA molecules that are co-expressed in the same living cells. This article is protected by copyright. All rights reserved.

    ID:849
  16. Shugay M., Bolotin D.A., Putintseva E.V., Pogorelyy M.V., Mamedov I.Z., Chudakov D.M. (2013). Huge Overlap of Individual TCR Beta Repertoires. Front Immunol 4, 466 ID:1275
  17. Putintseva E.V., Britanova O.V., Staroverov D.B., Merzlyak E.M., Turchaninova M.A., Shugay M., Bolotin D.A., Pogorelyy M.V., Mamedov I.Z., Bobrynina V., Maschan M., Lebedev Y.B., Chudakov D.M. (2013). Mother and child T cell receptor repertoires: deep profiling study. Front Immunol 4, 463 [+]

    The relationship between maternal and child immunity has been actively studied in the context of complications during pregnancy, autoimmune diseases, and haploidentical transplantation of hematopoietic stem cells and solid organs. Here, we have for the first time used high-throughput Illumina HiSeq sequencing to perform deep quantitative profiling of T cell receptor (TCR) repertoires for peripheral blood samples of three mothers and their six children. Advanced technology allowed accurate identification of 5 × 10(5) to 2 × 10(6) TCR beta clonotypes per individual. We performed comparative analysis of these TCR repertoires with the aim of revealing characteristic features that distinguish related mother-child pairs, such as relative TCR beta variable segment usage frequency and relative overlap of TCR beta complementarity-determining region 3 (CDR3) repertoires. We show that thymic selection essentially and similarly shapes the initial output of the TCR recombination machinery in both related and unrelated pairs, with minor effect from inherited differences. The achieved depth of TCR profiling also allowed us to test the hypothesis that mature T cells transferred across the placenta during pregnancy can expand and persist as functional microchimeric clones in their new host, using characteristic TCR beta CDR3 variants as clonal identifiers.

    ID:1276
  18. Bolotin D.A., Mamedov I.Z., Britanova O.V., Zvyagin I.V., Shagin D., Ustyugova S.V., Turchaninova M.A., Lukyanov S., Lebedev Y.B., Chudakov D.M. (2012). Next generation sequencing for TCR repertoire profiling: platform-specific features and correction algorithms. European journal of immunology , [+]

    The T-cell receptor (TCR) repertoire is a mirror of the human immune system that reflects processes caused by infections, cancer, autoimmunity, and aging. Next generation sequencing (NGS) is becoming a powerful tool for deep TCR profiling; yet, questions abound regarding the methodological approaches for sample preparation and correct data interpretation. Accumulated PCR and sequencing errors along with library preparation bottlenecks and uneven PCR efficiencies lead to information loss, biased quantification, and generation of huge artificial TCR diversity. Here, we compare Illumina, 454, and Ion Torrent platforms for individual TCR profiling, evaluate the rate and character of errors, and propose advanced platform-specific algorithms to correct massive sequencing data. These developments are applicable to a wide variety of NGS applications. We demonstrate that advanced correction allows the removal of the majority of artificial TCR diversity with concomitant rescue of most of the sequencing information. Thus, this correction enhances the accuracy of clonotype identification and quantification as well as overall TCR diversity measurements.

    ID:733
  19. Britanova O.V., Bochkova A.G., Staroverov D.B., Fedorenko D.A., Bolotin D.A., Mamedov I.Z., Turchaninova M.A., Putintseva E.V., Kotlobay A.A., Lukyanov S., Novik A.A., Lebedev Y.B., Chudakov D.M. (2012). First autologous hematopoietic SCT for ankylosing spondylitis: a case report and clues to understanding the therapy. Bone marrow transplantation , ID:732
  20. Shemiakina I.I., Ermakova G.V., Cranfill P.J., Baird M.A., Evans R.A., Souslova E.A., Staroverov D.B., Gorokhovatsky A.Y., Putintseva E.V., Gorodnicheva T.V., Chepurnykh T.V., Strukova L., Lukyanov S., Zaraisky A.G., Davidson M.W., Chudakov D.M., Shcherbo D. (2012). A monomeric red fluorescent protein with low cytotoxicity. Nat Commun 3, 1204 [+]

    Multicolour labelling with fluorescent proteins is frequently used to differentially highlight specific structures in living systems. Labelling with fusion proteins is particularly demanding and is still problematic with the currently available palette of fluorescent proteins that emit in the red range due to unsuitable subcellular localization, protein-induced toxicity and low levels of labelling efficiency. Here we report a new monomeric red fluorescent protein, called FusionRed, which demonstrates both high efficiency in fusions and low toxicity in living cells and tissues.

    ID:832
  21. Mamedov I.Z., Britanova O.V., Bolotin D.A., Chkalina A.V., Staroverov D.B., Zvyagin I.V., Kotlobay A.A., Turchaninova M.A., Fedorenko D.A., Novik A.A., Sharonov G.V., Lukyanov S., Chudakov D.M., Lebedev Y.B. (2011). Quantitative tracking of T cell clones after haematopoietic stem cell transplantation. EMBO Mol Med 3 (4), 201–7 [+]

    Autologous haematopoietic stem cell transplantation is highly efficient for the treatment of systemic autoimmune diseases, but its consequences for the immune system remain poorly understood. Here, we describe an optimized RNA-based technology for unbiased amplification of T cell receptor beta-chain libraries and use it to perform the first detailed, quantitative tracking of T cell clones during 10 months after transplantation. We show that multiple clones survive the procedure, contribute to the immune response to activated infections, and form a new skewed and stable T cell receptor repertoire.

    ID:453
  22. Luker K.E., Mihalko L.A., Schmidt B.T., Lewin S.A., Ray P., Shcherbo D., Chudakov D.M., Luker G.D. (2011). In vivo imaging of ligand receptor binding with Gaussia luciferase complementation. Nat. Med. 18 (1), 172–7 [+]

    Studies of ligand-receptor binding and the development of receptor antagonists would benefit greatly from imaging techniques that translate directly from cell-based assays to living animals. We used Gaussia luciferase protein fragment complementation to quantify the binding of chemokine (C-X-C motif) ligand 12 (CXCL12) to chemokine (C-X-C motif) receptor 4 (CXCR4) and CXCR7. Studies established that small-molecule inhibitors of CXCR4 or CXCR7 specifically blocked CXCL12 binding in cell-based assays and revealed differences in kinetics of inhibiting chemokine binding to each receptor. Bioluminescence imaging showed CXCL12-CXCR7 binding in primary and metastatic tumors in a mouse model of breast cancer. We used this imaging technique to quantify drug-mediated inhibition of CXCL12-CXCR4 binding in living mice. We expect this imaging technology to advance research in areas such as ligand-receptor interactions and the development of new therapeutic agents in cell-based assays and small animals.

    ID:633
  23. Shcherbo D., Shemiakina I.I., Ryabova A.V., Luker K.E., Schmidt B.T., Souslova E.A., Gorodnicheva T.V., Strukova L., Shidlovskiy K.M., Britanova O.V., Zaraisky A.G., Lukyanov K.A., Loschenov V.B., Luker G.D., Chudakov D.M. (2010). Near-infrared fluorescent proteins. Nat. Methods 7 (10), 827–9 [+]

    Fluorescent proteins with emission wavelengths in the near-infrared and infrared range are in high demand for whole-body imaging techniques. Here we report near-infrared dimeric fluorescent proteins eqFP650 and eqFP670. To our knowledge, eqFP650 is the brightest fluorescent protein with emission maximum above 635 nm, and eqFP670 displays the most red-shifted emission maximum and high photostability.

    ID:369
  24. Zvyagin I.V., Mamedov I.Z., Britanova O.V., Staroverov D.B., Nasonov E.L., Bochkova A.G., Chkalina A.V., Kotlobay A.A., Korostin D.O., Rebrikov D.V., Lukyanov S., Lebedev Y.B., Chudakov D.M. (2010). Contribution of functional KIR3DL1 to ankylosing spondylitis. Cellular & molecular immunology , [+]

    Increasing evidence points to a role for killer immunoglobulin-like receptors (KIRs) in the development of autoimmune diseases. In particular, a positive association of KIR3DS1 (activating receptor) and a negative association of KIR3DL1 (inhibitory receptor) alleles with ankylosing spondylitis (AS) have been reported by several groups. However, none of the studies analyzed these associations in the context of functionality of polymorphic KIR3DL1. To better understand how the KIR3DL1/3DS1 genes determine susceptibility to AS, we analyzed the frequencies of alleles and genotypes encoding functional (KIR3DL1*F) and non-functional (KIR3DL1*004) receptors. We genotyped 83 AS patients and 107 human leukocyte antigen (HLA)-B27-positive healthy controls from the Russian Caucasian population using a two-stage sequence-specific primer PCR, which distinguishes KIR3DS1, KIR3DL1*F and KIR3DL1*004 alleles. For the patients carrying two functional KIR3DL1 alleles, those alleles were additionally genotyped to identify KIR3DL1*005 and KIR3DL1*007 alleles, which are functional but are expressed at low levels. KIR3DL1 was negatively associated with AS at the expense of KIR3DL1*F but not of KIR3DL1*004. This finding indicates that the inhibitory KIR3DL1 receptor protects against the development of AS and is not simply a passive counterpart of the segregating KIR3DS1 allele encoding the activating receptor. However, analysis of genotype frequencies indicates that the presence of KIR3DS1 is a more important factor for AS susceptibility than the absence of KIR3DL1*F. The activation of either natural killer (NK) or T cells via the KIR3DS1 receptor can be one of the critical events in AS development, while the presence of the functional KIR3DL1 receptor has a protective effect. Nevertheless, even individuals with a genotype that carried two inhibitory KIR3DL1 alleles expressed at high levels could develop AS.Cellular & Molecular Immunology advance online publication, 6 September 2010; doi:10.1038/cmi.2010.42.

    ID:370
  25. Chudakov D.M., Matz M.V., Lukyanov S., Lukyanov K.A. (2010). Fluorescent proteins and their applications in imaging living cells and tissues. Physiol. Rev. 90 (3), 1103–63 [+]

    Green fluorescent protein (GFP) from the jellyfish Aequorea victoria and its homologs from diverse marine animals are widely used as universal genetically encoded fluorescent labels. Many laboratories have focused their efforts on identification and development of fluorescent proteins with novel characteristics and enhanced properties, resulting in a powerful toolkit for visualization of structural organization and dynamic processes in living cells and organisms. The diversity of currently available fluorescent proteins covers nearly the entire visible spectrum, providing numerous alternative possibilities for multicolor labeling and studies of protein interactions. Photoactivatable fluorescent proteins enable tracking of photolabeled molecules and cells in space and time and can also be used for super-resolution imaging. Genetically encoded sensors make it possible to monitor the activity of enzymes and the concentrations of various analytes. Fast-maturing fluorescent proteins, cell clocks, and timers further expand the options for real time studies in living tissues. Here we focus on the structure, evolution, and function of GFP-like proteins and their numerous applications for in vivo imaging, with particular attention to recent techniques.

    ID:362
  26. Bogdanov A.M., Bogdanova E.A., Chudakov D.M., Gorodnicheva T.V., Lukyanov S., Lukyanov K.A. (2009). Cell culture medium affects GFP photostability: a solution. Nat. Methods 6 (12), 859–60 ID:298
  27. Mamedov I.Z., Britanova O.V., Chkalina A.V., Staroverov D.B., Amosova A.L., Mishin A.S., Kurnikova M.A., Zvyagin I.V., Mutovina Z.Y., Gordeev A.V., Khaidukov S.V., Sharonov G.V., Shagin D.A., Chudakov D.M., Lebedev Y.B. (2009). Individual characterization of stably expanded T cell clones in ankylosing spondylitis patients. Autoimmunity 42 (6), 525–36 [+]

    Ankylosing spondylitis (AS) is commonly characterized by clonal expansions of T cells. However, these clonal populations are poorly studied and their role in disease initiation and progression remains unclear. Here, we performed mass sequencing of TCR V beta libraries to search for the expanded T cell clones for two AS patients. A number of clones comprising more than 5% of the corresponding TCR V beta family were identified in both patients. For the first time, expanded clones were shown to be stably abundant in blood samples of AS patients for the prolonged period (1.5 and 2.5 years for two patients, correspondingly). These clones were individually characterized in respect to their differentiation status using fluorescent cell sorting with CD27, CD28, and CD45RA markers followed by quantitative identification of each clone within corresponding fraction using real time PCR analysis. Stable clones differed in phenotype and several were shown to belong to the proinflammatory CD27 - /CD28 - population. Their potentially cytotoxic status was confirmed by staining with perforin-specific antibodies. Search for the TCR V beta CRD3 sequences homologous to the identified clones revealed close matches with the previously reported T cell clones from AS and reactive arthritis patients, thus supporting their role in the disease and proposing consensus TCR V beta CDR3 motifs for AS. Interestingly, these motifs were also found to have homology with earlier reported virus-specific CDR3 variants, indicating that viral infections could play role in development of AS.

    ID:276
  28. Serebrovskaya E.O., Edelweiss E.F., Stremovskiy O.A., Lukyanov K.A., Chudakov D.M., Deyev S.M. (2009). Targeting cancer cells by using an antireceptor antibody-photosensitizer fusion protein. Proc. Natl. Acad. Sci. U.S.A. 106 (23), 9221–5 [+]

    Antibody-photosensitizer chemical conjugates are used successfully to kill cancer cells in photodynamic therapy. However, chemical conjugation of photosensitizers presents several limitations, such as poor reproducibility, aggregation, and free photosensitizer impurities. Here, we report a fully genetically encoded immunophotosensitizer, consisting of a specific anti-p185(HER-2-ECD) antibody fragment 4D5scFv fused with the phototoxic fluorescent protein KillerRed. Both parts of the recombinant protein preserved their functional properties: high affinity to antigen and light activation of sensitizer. 4D5scFv-KillerRed showed fine targeting properties and efficiently killed p185(HER-2-ECD)-expressing cancer cells upon light irradiation. It also showed a remarkable additive effect with the commonly used antitumor agent cisplatin, further demonstrating the potential of the approach.

    ID:300
  29. Bogdanov A.M., Mishin A.S., Yampolsky I.V., Belousov V.V., Chudakov D.M., Subach F.V., Verkhusha V.V., Lukyanov S., Lukyanov K.A. (2009). Green fluorescent proteins are light-induced electron donors. Nat. Chem. Biol.  (5), 459–461 [+]

    Proteins of the green fluorescent protein (GFP) family are well known owing to their unique biochemistry and extensive use as in vivo markers. We discovered that GFPs of diverse origins can act as light-induced electron donors in photochemical reactions with various electron acceptors, including biologically relevant ones. Moreover, via green-to-red GFP photoconversion, this process can be observed in living cells without additional treatment.

    ID:22
  30. Shcherbo D., Murphy C.S., Ermakova G.V., Solovieva E.A., Chepurnykh T.V., Shcheglov A.S., Verkhusha V.V., Pletnev V.Z., Hazelwood K.L., Roche P.M., Lukyanov S., Zaraisky A.G., Davidson M.W., Chudakov D.M. (2009). Far-red fluorescent tags for protein imaging in living tissues. Biochem. J. 418 (3), 567–74 [+]

    Разработан яркий, мономерный, фотостабильный, pH-стабильный, дальне-красный флуоресцентый белок mKate2. Белок mKate2 хорошо показал себя в качестве метки во фьюзах с рядом белков, как в культуре клеток, так и в трансгенных лягушках Xenopus laevis (совместно с лабораторией Молекулярных основ эмбриогенеза ИБХ РАН).

    ID:31
  31. Zhang L., Gurskaya N.G., Kopantseva Y.E., Mudrik N.N., Vagner L.L., Lukyanov K.A., Chudakov D.M. (2009). [Identification of the amino acid residues responsible for the reversible photoconversion of the monomeric red fluorescent protein TagRFP protein]. Bioorg. Khim. 36 (2), 187–92 [+]

    The site-directed mutagenesis of the monomeric red fluorescent protein TagRFP and its variants was performed with the goal of generating reversibly photoactivatable fluorescent proteins. Amino acids at positions 69, 148, 165, 179, and 181 (enumeration according to the green fluorescent protein GFP) were shown to play a key role in the manifestation of the photoactivatable properties. A reversibly photoactivatable red fluorescent protein KFP-HC with excitation and emission maxima at 585 and 615 nm, respectively, was generated. The KFP-HC fluorescent intensity was decreased by 5-10 times under green light (530-560 nm) irradiation (due to the fall of the fluorescence quantum yield) and restored under irradiation with blue light (450-490 nm) or after incubation in the dark (time of half reconstruction of 30 min).

    ID:361
  32. Shcherbo D., Merzlyak E.M., Chepurnykh T.V., Fradkov A.F., Ermakova G.V., Solovieva E.A., Lukyanov K.A., Bogdanova E.A., Zaraisky A.G., Lukyanov S., Chudakov D.M. (2007). Bright far-red fluorescent protein for whole-body imaging. Nat. Methods 4 (9), 741–6 [+]

    Разработан новый флуоресцентный белок Katushka, обладающий флуоресценцией в дальне-красной области спектра, которая является предпочтительной для анализа сигнала внутри тканей животных. Katushka в десять раз ярче, чем созданные ранее дальне-красные флуоресцентные белки и характеризуется высокой скоростью созревания, высокой рН-стабильностью и фотостабильностью. Это делает новый белок идеальным инструментом для прижизненного мечения клеток внутри целых организмов. Создан мономерный вариант белка Katushka, названный mKate, для исследования внутриклеточной локализации белков.

    ID:76
  33. Merzlyak E.M., Goedhart J., Shcherbo D., Bulina M.E., Shcheglov A.S., Fradkov A.F., Gaintzeva A., Lukyanov K.A., Lukyanov S., Gadella T.W., Chudakov D.M. (2007). Bright monomeric red fluorescent protein with an extended fluorescence lifetime. Nat. Methods 4 (7), 555–7 [+]

    Fluorescent proteins have become extremely popular tools for in vivo imaging and especially for the study of localization, motility and interaction of proteins in living cells. Here we report TagRFP, a monomeric red fluorescent protein, which is characterized by high brightness, complete chromophore maturation, prolonged fluorescence lifetime and high pH-stability. These properties make TagRFP an excellent tag for protein localization studies and fluorescence resonance energy transfer (FRET) applications.

    ID:277
  34. Souslova E.A., Chudakov D.M. (2007). Genetically encoded intracellular sensors based on fluorescent proteins. Biochemistry Mosc. 72 (7), 683–97 [+]

    Green fluorescent protein from Aequorea victoria and its many homologs are now widely used in basic and applied research. These genetically encoded fluorescent markers can detect localization of cell proteins and organelles in living cells and also cells and tissues in living organisms. Unique instruments and methods for studies of molecular biology of a cell and high throughput drug screenings are based on fluorescent proteins. This review deals with the most intensively evolving directions in this field, the development of genetically encoded sensors. Changes in their spectral properties are used for monitoring of cell enzyme activities or changes in concentrations of particular molecules.

    ID:308
  35. Chudakov D.M., Lukyanov S., Lukyanov K.A. (2007). Tracking intracellular protein movements using photoswitchable fluorescent proteins PS-CFP2 and Dendra2. Nat Protoc 2 (8), 2024–32 [+]

    A number of photoactivatable GFP-like fluorescent proteins (PAFPs) have been reported whose fluorescence can be switched on or whose fluorescent state can be modified by relatively intense irradiation at a specific wavelength. The use of these proteins gives unique opportunities to photolabel and track fusion proteins in a living cell. Here, we provide a protocol for the primary visualization, photoactivation and tracking of two monomeric PAFPs recently developed in our lab. Both these proteins, PS-CFP2 and Dendra2, are fluorescent and can be visualized before photoactivation. Upon photoactivation, their excitation and emission spectra undergo a dramatic red shift. The brightness of their initial and photoconverted states, along with the high dynamic ranges of both proteins, make them an attractive tool for protein photolabeling. Excluding genetic constructs cloning, cell culturing and transfection, the whole protocol may take anywhere from 10 min to several hours, depending on motility of the protein being studied.

    ID:307
  36. Evdokimov A.G., Pokross M.E., Egorov N.S., Zaraisky A.G., Yampolsky I.V., Merzlyak E.M., Shkoporov A.N., Sander I., Lukyanov K.A., Chudakov D.M. (2006). Structural basis for the fast maturation of Arthropoda green fluorescent protein. EMBO Rep. 7 (10), 1006–12 [+]

    Since the cloning of Aequorea victoria green fluorescent protein (GFP) in 1992, a family of known GFP-like proteins has been growing rapidly. Today, it includes more than a hundred proteins with different spectral characteristics cloned from Cnidaria species. For some of these proteins, crystal structures have been solved, showing diversity in chromophore modifications and conformational states. However, we are still far from a complete understanding of the origin, functions and evolution of the GFP family. Novel proteins of the family were recently cloned from evolutionarily distant marine Copepoda species, phylum Arthropoda, demonstrating an extremely rapid generation of fluorescent signal. Here, we have generated a non-aggregating mutant of Copepoda fluorescent protein and solved its high-resolution crystal structure. It was found that the protein beta-barrel contains a pore, leading to the chromophore. Using site-directed mutagenesis, we showed that this feature is critical for the fast maturation of the chromophore.

    ID:280
  37. Chudakov D.M., Chepurnykh T.V., Belousov V.V., Lukyanov S., Lukyanov K.A. (2006). Fast and precise protein tracking using repeated reversible photoactivation. Traffic 7 (10), 1304–10 [+]

    Photoactivatable fluorescent proteins opened principally novel possibilities to study proteins' movement pathways. In particular, reversibly photoactivatable proteins enable multiple tracking experiments in a long-drawn work with a single cell. Here we report 'protein rivers tracking' technique based on repeated identical rounds of photoactivation and subsequent images averaging, which results in dramatic increase of imaging resolution for fast protein movement events.

    ID:281
  38. Bulina M.E., Lukyanov K.A., Britanova O.V., Onichtchouk D., Lukyanov S., Chudakov D.M. (2006). Chromophore-assisted light inactivation (CALI) using the phototoxic fluorescent protein KillerRed. Nat Protoc 1 (2), 947–53 [+]

    The phototoxic red fluorescent GFP-like protein KillerRed has recently been described. The phototoxicity of KillerRed exceeds that of EGFP by at least 1,000-fold, making it the first fully genetically encoded photosensitizer. KillerRed opens up new possibilities for precise light-induced cell killing and target protein inactivation. Because KillerRed is encoded by a gene, it can be expressed in a spatially and temporally regulated manner, under a chosen promoter, and fused with the desired protein of interest or localization signal. Here we provide a protocol for target protein inactivation in cell culture using KillerRed. As KillerRed is a new tool, the protocol focuses on aspects that will allow users to maximize the potential of this protein, guiding the design of chimeric constructs, recommended control experiments and preferred illumination parameters. The protocol, which describes target protein visualization and subsequent inactivation, is a 2- or 3-d procedure.

    ID:279
  39. Bulina M.E., Chudakov D.M., Britanova O.V., Yanushevich Y.G., Staroverov D.B., Chepurnykh T.V., Merzlyak E.M., Shkrob M.A., Lukyanov S., Lukyanov K.A. (2006). A genetically encoded photosensitizer. Nat. Biotechnol. 24 (1), 95–9 [+]

    Photosensitizers are chromophores that generate reactive oxygen species (ROS) upon light irradiation. They are used for inactivation of specific proteins by chromophore-assisted light inactivation (CALI) and for light-induced cell killing in photodynamic therapy. Here we report a genetically encoded photosensitizer, which we call KillerRed, developed from the hydrozoan chromoprotein anm2CP, a homolog of green fluorescent protein (GFP). KillerRed generates ROS upon irradiation with green light. Whereas known photosensitizers must be added to living systems exogenously, KillerRed is fully genetically encoded. We demonstrate the utility of KillerRed for light-induced killing of Escherichia coli and eukaryotic cells and for inactivating fusions to beta-galactosidase and phospholipase Cdelta1 pleckstrin homology domain.

    ID:283
  40. Chudakov D.M., Lukyanov S., Lukyanov K.A. (2005). Fluorescent proteins as a toolkit for in vivo imaging. Trends Biotechnol. 23 (12), 605–13 [+]

    Green fluorescent protein (GFP) from the jellyfish Aequorea victoria, and its mutant variants, are the only fully genetically encoded fluorescent probes available and they have proved to be excellent tools for labeling living specimens. Since 1999, numerous GFP homologues have been discovered in Anthozoa, Hydrozoa and Copepoda species, demonstrating the broad evolutionary and spectral diversity of this protein family. Mutagenic studies gave rise to diversified and optimized variants of fluorescent proteins, which have never been encountered in nature. This article gives an overview of the GFP-like proteins developed to date and their most common applications to study living specimens using fluorescence microscopy.

    ID:285
  41. Lukyanov K.A., Chudakov D.M., Lukyanov S., Verkhusha V.V. (2005). Innovation: Photoactivatable fluorescent proteins. Nat. Rev. Mol. Cell Biol. 6 (11), 885–91 [+]

    The fluorescence characteristics of photoactivatable proteins can be controlled by irradiating them with light of a specific wavelength, intensity and duration. This provides unique possibilities for the optical labelling and tracking of living cells, organelles and intracellular molecules in a spatio-temporal manner. Here, we discuss the properties of the available photoactivatable fluorescent proteins and their potential applications.

    ID:286
  42. Chudakov D.M., Verkhusha V.V., Staroverov D.B., Souslova E.A., Lukyanov S., Lukyanov K.A. (2004). Photoswitchable cyan fluorescent protein for protein tracking. Nat. Biotechnol. 22 (11), 1435–9 [+]

    In recent years diverse photolabeling techniques using green fluorescent protein (GFP)-like proteins have been reported, including photoactivatable PA-GFP, photoactivatable protein Kaede, the DsRed 'greening' technique and kindling fluorescent proteins. So far, only PA-GFP, which is monomeric and gives 100-fold fluorescence contrast, could be applied for protein tracking. Here we describe a dual-color monomeric protein, photoswitchable cyan fluorescent protein (PS-CFP). PS-CFP is capable of efficient photoconversion from cyan to green, changing both its excitation and emission spectra in response to 405-nm light irradiation. Complete photoactivation of PS-CFP results in a 1,500-fold increase in the green-to-cyan fluorescence ratio, making it the highest-contrast monomeric photoactivatable fluorescent protein described to date. We used PS-CFP as a photoswitchable tag to study trafficking of human dopamine transporter in living cells. At moderate excitation intensities, PS-CFP can be used as a pH-stable cyan label for protein tagging and fluorescence resonance energy transfer applications.

    ID:289
  43. Bulina M.E., Lukyanov K.A., Yampolsky I.V., Chudakov D.M., Staroverov D.B., Shcheglov A.S., Gurskaya N.G., Lukyanov S. (2004). New class of blue animal pigments based on Frizzled and Kringle protein domains. J. Biol. Chem. 279 (42), 43367–70 [+]

    The nature of coloration in many marine animals remains poorly investigated. Here we studied the blue pigment of a scyfoid jellyfish Rhizostoma pulmo and determined it to be a soluble extracellular 30-kDa chromoprotein with a complex absorption spectrum peaking at 420, 588, and 624 nm. Furthermore, we cloned the corresponding cDNA and confirmed its identity by immunoblotting and mass spectrometry experiments. The chromoprotein, named rpulFKz1, consists of two domains, a Frizzled cysteine-rich domain and a Kringle domain, inserted into one another. Generally, Frizzleds are members of a basic Wnt signal transduction pathway investigated intensely with regard to development and cancerogenesis. Kringles are autonomous structural domains found throughout the blood clotting and fibrinolytic proteins. Neither Frizzled and Kringle domains association with any type of coloration nor Kringle intrusion into Frizzled sequence was ever observed. Thus, rpulFKz1 represents a new class of animal pigments, whose chromogenic group remains undetermined. The striking homology between a chromoprotein and members of the signal transduction pathway provides a novel node in the evolution track of growth factor-mediated morphogenesis compounds.

    ID:290
  44. Chudakov D.M., Lukyanov K.A. (2003). Use of green fluorescent protein (GFP) and its homologs for in vivo protein motility studies. Biochemistry Mosc. 68 (9), 952–7 [+]

    Green fluorescent protein (GFP) and its homologs are widely used as fluorescent markers of gene expression and for determination of protein localization and motility in living cells. In particular, based on GFP and GFP-like proteins a number of techniques have been developed that can be used either to estimate protein mobility in living cells, or to introduce a distinctive fluorescent signal in order to track the movement of labeled molecules directly. Considerable progress in the development of such technologies in the last two or three years motivates us to reevaluate the present scope of biotechnological instruments in studies of protein movement in cells.

    ID:292
  45. Chudakov D.M., Feofanov A.V., Mudrik N.N., Lukyanov S., Lukyanov K.A. (2003). Chromophore environment provides clue to "kindling fluorescent protein" riddle. J. Biol. Chem. 278 (9), 7215–9 [+]

    asCP, the unique green fluorescent protein-like nonfluorescent chromoprotein from the sea anemone Anemonia sulcata, becomes fluorescent ("kindles") upon green light irradiation, with maximum emission at 595 nm. The kindled protein then relaxes to a nonfluorescent state or can be "quenched" instantly by blue light irradiation. In this work, we used asCP mutants to investigate the mechanism underlying kindling. Using site-directed mutagenesis we showed that amino acids spatially surrounding Tyr(66) in the chromophore are crucial for kindling. We propose a model of the kindling mechanism, in which the key event is chromophore turning or cis-trans isomerization. Using site-directed mutagenesis we also managed to transfer the kindling property to the two other coral chromoproteins. Remarkably, most kindling mutants were capable of both reversible and irreversible kindling. Also, we obtained novel variants that kindled upon blue light irradiation. The diversity of photoactivated fluorescent proteins that can be developed by site-directed mutagenesis is promising for biotechnological needs.

    ID:293
  46. Chudakov D.M., Belousov V.V., Zaraisky A.G., Novoselov V.V., Staroverov D.B., Zorov D.B., Lukyanov S., Lukyanov K.A. (2003). Kindling fluorescent proteins for precise in vivo photolabeling. Nat. Biotechnol. 21 (2), 191–4 [+]

    Photobleaching of green fluorescent protein (GFP) is a widely used approach for tracking the movement of subcellular structures and intracellular proteins. Although photobleaching is a powerful technique, it does not allow direct tracking of an object's movement and velocity within a living cell. Direct tracking becomes possible only with the introduction of a photoactivated fluorescent marker. A number of previous studies have reported optically induced changes in the emission spectra of fluorescent proteins. However, the ideal photoactivated fluorescent marker should be a nonfluorescent tag capable of "switching on" (i.e., becoming fluorescent) in response to irradiation by light of a particular wavelength, intensity, and duration. In this report, we generated a mutant of Anemonia sulcata chromoprotein asCP. The mutant protein is capable of unique irreversible photoconversion from the nonfluorescent to a stable bright-red fluorescent form ("kindling"). This "kindling fluorescent protein" (KFP1) can be used for precise in vivo photolabeling to track the movements of cells, organelles, and proteins. We used KFP1 for in vivo cell labeling in mRNA microinjection assays to monitor Xenopus laevis embryo development and to track mitochondrial movement in mammalian cells.

    ID:73