Группа молекулярной физиологии

Группа занимается поиском тирозинкиназных рецепторов, которые активируются изменением внеклеточного pH.

При помощи компьютерной программы AcalPred сотрудники предсказывают рецепторы, которые имеют потенциал для активации при изменении внеклеточного pH. В результате исследователям удалось найти спектр рецепторов, некоторые из которых фосфорилируются при защелачивании внеклеточной среды. Часть рецепторов имеют прямое онкологическое влияние и выступают в качестве онкомаркеров.

Группа создана в 2013 году.

Ф.И.О.ДолжностьКонтакты
Деев Игорь Евгеньевич, к. ф.-м. н.с.н.с.deyevie@ibch.ru+7(495)335-41-77, +7(916)354-83-57
Жевленёв Егор Сергеевичм.н.с.egor.zhevlenev@gmail.com+7(495)335-41-77

Избранные публикации

  1. Deyev I.E., Chachina N.A., Zhevlenev E.S., Petrenko A.G. (2017). Site-Directed Mutagenesis of the Fibronectin Domains in Insulin Receptor-Related Receptor. Int J Mol Sci 18 (11), [+]

    The orphan insulin receptor-related receptor (IRR), in contrast to its close homologs, the insulin receptor (IR) and insulin-like growth factor receptor (IGF-IR) can be activated by mildly alkaline extracellular medium. We have previously demonstrated that IRR activation is defined by its extracellular region, involves multiple domains, and shows positive cooperativity with two synergistic sites. By the analyses of point mutants and chimeras of IRR with IR in, we now address the role of the fibronectin type III (FnIII) repeats in the IRR pH-sensing. The first activation site includes the intrinsically disordered subdomain ID (646-716) within the FnIII-2 domain at the C-terminus of IRR alpha subunit together with closely located residues L135, G188, R244, H318, and K319 of L1 and C domains of the second subunit. The second site involves residue T582 of FnIII-1 domain at the top of IRR lambda-shape pyramid together with M406, V407, and D408 from L2 domain within the second subunit. A possible importance of the IRR carbohydrate moiety for its activation was also assessed. IRR is normally less glycosylated than IR and IGF-IR. Swapping both FnIII-2 and FnIII-3 IRR domains with those of IR shifted beta-subunit mass from 68 kDa for IRR to about 100 kDa due to increased glycosylation and abolished the IRR pH response. However, mutations of four asparagine residues, potential glycosylation sites in chimera IRR with swapped FnIII-2/3 domains of IR, decreased the chimera glycosylation and resulted in a partial restoration of IRR pH-sensing activity, suggesting that the extensive glycosylation of FnIII-2/3 provides steric hindrance for the alkali-induced rearrangement of the IRR ectodomain.

    ID:1951
  2. Deyev I.E., Popova N.V., Serova O.V., Zhenilo S.V., Regoli M., Bertelli E., Petrenko A.G. (2017). Alkaline pH induces IRR-mediated phosphorylation of IRS-1 and actin cytoskeleton remodeling in a pancreatic beta cell line. Biochimie 138, 62–69 [+]

    Secretion of mildly alkaline (pH 8.0-8.5) juice to intestines is one of the key functions of the pancreas. Recent reports indicate that the pancreatic duct system containing the alkaline juice may adjoin the endocrine cells of pancreatic islets. We have previously identified the insulin receptor-related receptor (IRR) that is expressed in islets as a sensor of mildly alkaline extracellular media. In this study, we show that those islet cells that are in contact with the excretory ducts are also IRR-expressing cells. We further analyzed the effects of alkaline media on pancreatic beta cell line MIN6. Activation of endogenous IRR but not of the insulin receptor was detected that could be inhibited with linsitinib. The IRR autophosphorylation correlated with pH-dependent linsitinib-sensitive activation of insulin receptor substrate 1 (IRS-1), the primary adaptor in the insulin signaling pathway. However, in contrast with insulin stimulation, no protein kinase B (Akt/PKB) phosphorylation was detected as a result of alkali treatment. We observed overexpression of several early response genes (EGR2, IER2, FOSB, EGR1 and NPAS4) upon alkali treatment of MIN6 cells but those were IRR-independent. The alkaline medium but not insulin also triggered actin cytoskeleton remodeling that was blocked by pre-incubation with linsitinib. We propose that the activation of IRR by alkali might be part of a local loop of signaling between the exocrine and endocrine parts of the pancreas where alkalinization of the juice facilitate insulin release that increases the volume of secreted juice to control its pH and bicabonate content.

    ID:1952

Деев Игорь Евгеньевич

  • Москва, ул. Миклухо-Маклая, 16/10 — На карте
  • ИБХ РАН, корп. 31, комн. 208
  • Тел.: +7(495)335-41-77
  • Эл. почта: deyevie@ibch.ru

Сайт-направленный мутагенез в фибронектиновых повторах в рецепторе IRR (2017-11-26)

Ранее мы продемонстрировали, что активация IRR определяется его внеклеточной областью, включает в себя несколько доменов и показывает положительную кооперативность с двумя синергетическими сайтами. Теперь мы рассмотрели роль FnIII повторов в рН-чувствительности IRR с помощью анализа точечных мутантов и химер IRR с рецептором инсулина (IR). Мы показали, что первый сайт активации включает в себя неупорядоченный участок (646-716) в домене FnIII-2 на С-конце IRR-альфа-субъединицы вместе с близко расположенными остатками L135, G188, R244, H318, K319 доменов L1 и C второй субъединицы. Второй сайт включает в себя остаток T582 домена FnIII-1 в верхней части пирамиды лямбда-формы IRR вместе с M406, V407, D408 из домена L2 во второй субъединице. Также была оценена возможная важность гликозилирования IRR для его активации. Обычно IRR менее гликозилирован, чем IR и IGF-IR. Замена доменов FnIII-2 и FnIII-3 в IRR на гомологичные домены из IR приводит к сдвигу массы β-субъединицы с 68 кДа для IRR до примерно 100 кДа из-за увеличения гликозилирования и отсутствию рН-чувствительность у этой химеры. Однако мутации четырех аспарагиновых остатков (сайтов гликозилирования в этой химере) приводили к уменьшению гликозилирования химер и к частичному восстановлению рН-чувствительности. Таким образом, мы предполагаем, что обширное гликозилирование FnIII-2 / 3 доменов обеспечивает стерическое препятствие для щелочной активации эктодомена IRR.

Публикации

  1. Deyev I.E., Chachina N.A., Zhevlenev E.S., Petrenko A.G. (2017). Site-Directed Mutagenesis of the Fibronectin Domains in Insulin Receptor-Related Receptor. Int J Mol Sci 18 (11), [+]

    The orphan insulin receptor-related receptor (IRR), in contrast to its close homologs, the insulin receptor (IR) and insulin-like growth factor receptor (IGF-IR) can be activated by mildly alkaline extracellular medium. We have previously demonstrated that IRR activation is defined by its extracellular region, involves multiple domains, and shows positive cooperativity with two synergistic sites. By the analyses of point mutants and chimeras of IRR with IR in, we now address the role of the fibronectin type III (FnIII) repeats in the IRR pH-sensing. The first activation site includes the intrinsically disordered subdomain ID (646-716) within the FnIII-2 domain at the C-terminus of IRR alpha subunit together with closely located residues L135, G188, R244, H318, and K319 of L1 and C domains of the second subunit. The second site involves residue T582 of FnIII-1 domain at the top of IRR lambda-shape pyramid together with M406, V407, and D408 from L2 domain within the second subunit. A possible importance of the IRR carbohydrate moiety for its activation was also assessed. IRR is normally less glycosylated than IR and IGF-IR. Swapping both FnIII-2 and FnIII-3 IRR domains with those of IR shifted beta-subunit mass from 68 kDa for IRR to about 100 kDa due to increased glycosylation and abolished the IRR pH response. However, mutations of four asparagine residues, potential glycosylation sites in chimera IRR with swapped FnIII-2/3 domains of IR, decreased the chimera glycosylation and resulted in a partial restoration of IRR pH-sensing activity, suggesting that the extensive glycosylation of FnIII-2/3 provides steric hindrance for the alkali-induced rearrangement of the IRR ectodomain.

    ID:1951