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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">vestnik-bio-msu</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник Московского университета. Серия 16. Биология</journal-title><trans-title-group xml:lang="en"><trans-title>Vestnik Moskovskogo universiteta. Seriya 16. Biologiya</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0137-0952</issn><publisher><publisher-name>Lomonosov Moscow State University,  School of Biology</publisher-name></publisher></journal-meta><article-meta><article-id custom-type="elpub" pub-id-type="custom">vestnik-bio-msu-474</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Молекулярная биология</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>Molecular biology</subject></subj-group></article-categories><title-group><article-title>ВЛИЯНИЕ ИОНОВ НАТРИЯ И КАЛИЯ НА КОНФОРМАЦИЮ ЛИНКЕРНЫХ УЧАСТКОВ НУКЛЕОСОМ</article-title><trans-title-group xml:lang="en"><trans-title>INFLUENCE OF SODIUM AND POTASSIUM IONS ON CONFORMATION OF LINKER PARTS OF NUCLEOSOMES</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Любителев</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Lyubitelev</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кафедра биоинженерии, биологический факультет</p><p>Россия, 119234, г. Москва, Ленинские горы, д. 1, стр. 12</p><p>аспирант кафедры биоинженерии биологического факультета МГУ. Тел 8 495-938-22-91</p></bio><bio xml:lang="en"><p>Bioengineering Department, School of Biology</p><p>Leninskiye Gory 1–12, Moscow, 119234, Russia</p></bio><email xlink:type="simple">varanus-salvator@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Студитский</surname><given-names>В. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Studitsky</surname><given-names>V. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кафедра биоинженерии, биологический факультет</p><p>Россия, 119234, г. Москва, Ленинские горы, д. 1, стр. 12</p><p>Cottman avenue 333, Philadelphia, 19111 Pennsylvania, USA</p><p>докт. биол. наук, гл. науч. сотр. кафедры биоинженерии биологического факультета МГУ. Тел. 8-495-938-22-91</p></bio><bio xml:lang="en"><p>Bioengineering Department, School of Biology</p><p>Leninskiye Gory 1–12, Moscow, 119234, Russia</p><p>333 Cottman avenue, Philadelphia, Pennsylvania 19111, USA</p></bio><email xlink:type="simple">vasily.studitsky@fccc.edu</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Феофанов</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Feofanov</surname><given-names>A. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кафедра биоинженерии, биологический факультет</p><p>Россия, 119234, г. Москва, Ленинские горы, д. 1, стр. 12</p><p>Россия, 117997, г. Москва, ул. Миклухо-Маклая, д. 16/10</p><p>докт. биол. наук, проф. кафедры биоинженерии биологического факультета МГУ, руководитель лаборатории оптической микроскопии и спектроскопии биомолекул ИБХ РАН. Тел. 8-495-336-64-55</p></bio><bio xml:lang="en"><p>Bioengineering Department, School of Biology</p><p>Leninskiye Gory 1–12, Moscow, 119234, Russia</p></bio><email xlink:type="simple">avfeofanov@yandex.ru</email><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кирпичников</surname><given-names>М. П.</given-names></name><name name-style="western" xml:lang="en"><surname>Kirpichnikov</surname><given-names>M. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кафедра биоинженерии, биологический факультет</p><p>Россия, 119234, г. Москва, Ленинские горы, д. 1, стр. 12</p><p>Россия, 117997, г. Москва, ул. Миклухо-Маклая, д. 16/10</p><p>акад. РАН, проф., докт. биол. наук, зав. кафедрой биоинженерии биологического факультета МГУ, зав. отделом биоинженерии ИБХ РАН. Тел.: 8-495-939-27-76</p></bio><bio xml:lang="en"><p>Bioengineering Department, School of Biology</p><p>Leninskiye Gory 1–12, Moscow, 119234, Russia</p><p>Miklukho-Maklaya ul. 16/10, 117997, Moscow, Russia</p></bio><email xlink:type="simple">kirpichnikov@inbox.ru</email><xref ref-type="aff" rid="aff-4"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Московский государственный университет имени М.В. Ломоносова<country>Россия</country></aff><aff xml:lang="en">Lomonosov Moscow State University<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Московский государственный университет имени М.В. Ломоносова&#13;
&#13;
Fox Chase Cancer Center<country>Россия</country></aff><aff xml:lang="en">Lomonosov Moscow State University&#13;
&#13;
Fox Chase Cancer Center<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru">Московский государственный университет имени М.В. Ломоносова&#13;
&#13;
Институт биоорганической химии имени академиков М.М. Шемякина и Ю.А. Овчинникова, РАН<country>Россия</country></aff><aff xml:lang="en">Lomonosov Moscow State University<country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-4"><aff xml:lang="ru">Московский государственный университет имени М.В. Ломоносова&#13;
&#13;
Институт биоорганической химии имени академиков М.М. Шемякина и Ю.А. Овчинникова, РАН<country>Россия</country></aff><aff xml:lang="en">Lomonosov Moscow State University&#13;
&#13;
Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences<country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2017</year></pub-date><pub-date pub-type="epub"><day>28</day><month>07</month><year>2017</year></pub-date><volume>72</volume><issue>3</issue><fpage>169</fpage><lpage>173</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Любителев А.В., Студитский В.М., Феофанов А.В., Кирпичников М.П., 2017</copyright-statement><copyright-year>2017</copyright-year><copyright-holder xml:lang="ru">Любителев А.В., Студитский В.М., Феофанов А.В., Кирпичников М.П.</copyright-holder><copyright-holder xml:lang="en">Lyubitelev A.V., Studitsky V.M., Feofanov A.V., Kirpichnikov M.P.</copyright-holder><license license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://vestnik-bio-msu.elpub.ru/jour/article/view/474">https://vestnik-bio-msu.elpub.ru/jour/article/view/474</self-uri><abstract><p>Структура хроматина и доступность ДНК для белков зависят от структуры “линкерной” ДНК, расположенной на входе в нуклеосому и выходе из неё. Поскольку ДНК является отрицательно заряженным полимером, конформация линкерной ДНК, в свою очередь, зависит от ионного микроокружения. В настоящей работе методом флуоресцентной микроскопии одиночных комплексов исследовано влияние ионов Na+ и K+ на структуру линкерной ДНК мононуклеосом. Выявлено, что нуклеосомы находятся в одном из двух конформационных состояний, заселённость которых существенно меняется после замены ионов K+ на Na+. Эти изменения, вероятно, обусловлены различным взаимодействием Na+ и K+ с ДНК в областях входа ДНК в нуклеосому и выхода из неё. Катион-зависимые изменения конформации линкерной ДНК могут менять топологические барьеры в нуклеосоме, структуру полинуклеосомного хроматина и влиять на взаимодействия с различными белковыми факторами.</p></abstract><trans-abstract xml:lang="en"><p>The structure of chromatin and DNA accessibility to proteins depend on the structure of DNA “linkers” entering and exiting the nucleosome. Since DNA is negatively charged, conformation of the DNA linkers, in turn, is likely affected by ionic microenvironment. Here method of fluorescence microscopy of single complexes was used to study the effect of Na+ and K+ ions on the structure of the DNA linkers. It was revealed that nucleosomes adopt one of two conformational states, and occupancy of these states is considerably changed after substitution of K+ ions by Na+. These changes are likely caused by different interaction of Na+ and K+ ions with DNA in the regions of entry and exit of DNA from the nucleosome. Cation- dependent changes in conformation of the DNA linkers can affect topological barriers in nucleosomes, structure of polynucleosome chromatin and interactions of DNA with different protein factors.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>хроматин</kwd><kwd>нуклеосома</kwd><kwd>линкеры</kwd><kwd>ионы натрия</kwd><kwd>ионы калия</kwd><kwd>флуоресценция</kwd><kwd>микроскопия</kwd><kwd>одиночная молекула</kwd></kwd-group><kwd-group xml:lang="en"><kwd>chromatin</kwd><kwd>nucleosome</kwd><kwd>linkers</kwd><kwd>sodium ions</kwd><kwd>potassium ions</kwd><kwd>fluorescence</kwd><kwd>microscopy</kwd><kwd>single molecule</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Ngo T.T., Zhang Q., Zhou R., Yodh J.G., Ha T. Asymmetric unwrapping of nucleosomes under tension directed by DNA local flexibility // Cell. 2015. Vol. 160 N 6. 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