Leader: Igor I. Kireev
The department was organized in 1965, led by prof. Yuri S. Chentsov. In 1991, prof. Vladimir Yu. Poliakov assumed a position of the department head. The main function of the Department is maintenance of Electron microscopy facility and providing assistance to the Institute researches in their experimental work that requires optical and electron microscopy. Research areasThe department also conducts its own research in two directions: studies of general principles in structural-functional organization of genetic apparatus of eukaryotes and studies of mechanisms of cell motility. This research was supported by grants from RFBR, CRDF, INTAS, Soros’ Fund, grants from the President of Russian Federation to support young researchers and doctors of science (Alieva I., Kireev I., Sheval E.) Research resultsSince 2002 till 2012, the following important results were obtained: The concept of a “modular” structure of eukaryotic chromosome has been proposed and experimentally confirmed, which postulates a hierarchy of macromolecular chromatin complexes – nucleomeres, chromomeres, chromonema within a mitotic and interphase chromosome. Such a “modular” principle of DNA compaction, on one hand, allows for local independent decondensation of DNA loci upon activation, while, on the other hand, limiting access to other DNA regions for site-specific DNA-binding proteins, such as DNA-methylases, TFs etc. (Zatsepina et al, 1983; Prusov et al, 1983, Sheval et al, 2002; Polyakov et al, 2006). It was also discovered that metaphase chromosome displays lateral differentiation where euchromatic transcriptionally-active and early-replicating chromosomal loci are preferentially located at the metaphase chromosome surface, while heterochromatin late-replicating loci occupy axial region (Kobliakova et al, 2005). Studies of the dynamics of condensin association with chromosomes during mitotic and meiotic chromosome compaction, as well as under conditions of inducible changes in chromosome compaction level in vivo showed that condensins do not drive chromosome condensation and chromosomal axis formation (Kireeva et al., 2004), neither do they directly stabilize compact chromosome structure(Timirbulatova et al, 2002). Rather, they are involved in recruiting other architectural chromosome proteins. Fully-functional condensin complex is assembled sequentially on chromosomes during meiotic prophase with CAP-D2/pEg7 subunit being among the first to bind to chromosomes. In addition, individual condensin subunits display targeting to different non-chromatin nuclear domains, such as Cajal bodies and nucleoli (Uzbekov et al., 2003; Beenders et al., 2003). The study of ultrastructure of replicating chromatin has demonstrated decondensation of chromomeres and chromonema in euchromatin decondence into 30-nm fibers and loose the ability to condense in response to divalent cations addition in vitro (Golyshev et al, 2007) while heterochromatin loci remain highly condensed during replication (Kireev et al, 2008). The original concept of microtubules growth and shortening as a process of single-dimencional diffusion was introduced that allowed quantitative description of MT behavior. It was proposed that the role of centrosome is not limited to MT nucleation but mainly concerns spatial organization of free MT network through a set of stable Mts attached to the centrosome. The study of in vitro cultivated human endotheliocytes expressing GFP-tagged cytoskeletal proteins revealed variations in dynamic interactions between fibrillar (MTs, actin filaments) and adhesive (focal contacts, VE-cadherin intercellular contacts) cytoskeletal structures in endotheliocytes under normal conditions and after administration of drugs compromising barrier function of endothelium (Birukova et al, 2004). The study of plus-end capping proteins of CLASP family in mitosis showed that these proteins regulate MT dynamics in interphase while in mitosis they are involved in mitotic spindle organization and correct kinetochore orientation (Mimori-Kiyosue et al, 2005). PrizesLomonosov Prize (V.Polyakov, O.Zatsepina), Shuvalov Prize (I.Alieva), IUPAB/UNESCO Prize (I.Alieva). Education activitiesGraduate and PhD students of the Department Dudnik O.A.(1990-1993), Mukharyamova K.Sh.(1990-1993), Smirnova O., Pudenko A.S., Artyomenko E., Koblyakova Yu.V., Krokhina T.B. (1985-1986), Tkachova N. (1985-1986)., Abaimova T. (1985-1989), Gornung E.A. (1983-1987), Frolova E.A. (1984-1988), Vladimirskaya E. (1997-1998)., Grabeklis S.A., Abumuslimov S.S. (1988-1991), Grigoriev I., Zhukova N., Yamshanov A.N. (1994-1996)., Gozak P. (1982-1983), and others. Lecture and practical courses
Alieva I.,m Kireev I., Kurchashova S., Uzbekov R. «Methods of cell biology in cytogenetics» (Faculty of Bioinformatics ad Bioengineering). V.Polyakov and R.Uzbekov eds. |
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Laboratories
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