vavilovВавиловский журнал генетики и селекцииVavilov Journal of Genetics and Breeding2500-3259Institute of Cytology and Genetics of Siberian Branch of the RAS10.18699/VJ16.198vavilov-854Research ArticleФилогенетика и эволюцияPhylogenetics and evolutionЭволюция CpG-островов путем тандемных дупликацийEvolution of CpG-islands by means of tandem duplicationsБабенкоВ. Н.BabenkoV. N.

Новосибирск, Россия

Novosibirsk, Russia

bob@bionet.nsc.ruОрловЮ. Л.OrlovY. L.

Новосибирск, Россия

Novosibirsk, Russia

ИсаковаЖ. Т.IsakovaZh. T.

Бишкек, Кыргызская Республика

Bishkek, Kyrgyzstan

АнтоновД. А.AntonovD. A.

Новосибирск, Россия

Novosibirsk, Russia

ВоеводаМ. И.VoevodaM. I.

Новосибирск, Россия

Novosibirsk, Russia

Федеральное государственное бюджетное научное учреждение «Федеральный исследовательский центр Институт цитологии и генетики Сибирского отделения Российской академии наук» Федеральное государственное автономное образовательное учреждение высшего образования «Новосибирский национальный исследовательский государственный университет»РоссияInstitute of Cytology and Genetics SB RAS Novosibirsk State UniversityRussian FederationНаучно-исследовательский институт молекулярной биологии и медицины при Национальном центре кардиологии и терапии им. Мирсаида Миррахимова при Министерстве здравоохранения Кыргызской РеспубликиКыргызстанInstitute of Molecular Biology and Medicine at National Center of Cardiology and Therapy named after academician Mirsaid Mirrakhimov under the Ministry of Health of the Kyrgyz RepublicKyrgyzstanФедеральное государственное бюджетное научное учреждение «Научно-исследовательский институт экспериментальной и клинической медицины»РоссияInstitute of Clinical and Experimental Medicine SB RASRussian FederationФедеральное государственное бюджетное научное учреждение «Федеральный исследовательский центр Институт цитологии и генетики Сибирского отделения Российской академии наук» Федеральное государственное бюджетное научное учреждение «Научно- исследовательский институт терапии и профилактической медицины» Сибирского отделения Российской академии медицинских наукРоссияInstitute of Cytology and Genetics SB RAS Research Institute of Internal and Preventive Medicine SB RAMSRussian Federation201602022017206804815Copyright © Бабенко В.Н., Орлов Ю.Л., Исакова Ж.Т., Антонов Д.А., Воевода М.И., 20172017Бабенко В.Н., Орлов Ю.Л., Исакова Ж.Т., Антонов Д.А., Воевода М.И.Babenko V.N., Orlov Y.L., Isakova Z.T., Antonov D.A., Voevoda M.I.This work is licensed under a Creative Commons Attribution 4.0 License.https://vavilov.elpub.ru/jour/article/view/854

CG-богатые острова (далее CpG-острова; CpG-islands, или CGI) являются важными функциональными элементами генома позвоночных. В частности, они инициируют транскрипцию как промоторы в большинстве (>50 %) генов позвоночных, в ряде случаев двунаправленную, в силу самокомплементарности cg динуклеотидов; формируют глобальный ландшафт метилирования; выступают как «выключатель» транскрипции через метилирование. Вырожденная природа CpG-островов (смещенный cg-состав) предполагает увеличение вероятности тандемных повторов и палиндромов внутри CpG-острова. Данная работа посвящена идентификации тандемных дупликаций полных CpG-островов, т. е. мегамономеров длиной 400–5000 п. н., в геноме человека. Были найдены меж- и внутригенные тандемные дупликации CpG- островов. Найденные межгенные CGI дупликации опосредовались через CG-богатые субцентромерные и теломерные сателлиты, а также SINE элементы. Высокое сходство мономеров тандемов в отдельных случаях предполагает существование давления отбора на структуру таких локусов. Исследование контекста межгенных тандемных CGI повторов указывает на их возможную роль в выравнивании cg-состава в геномном сегменте. Найденные тандемные CGI были транскрипционно активными в широком диапазоне тканей и клеточных линий. Рассмотренный феномен кластерной организации CGI наиболее выражен при рассмотрении хромосомы 19, известной своим избытком сегментных дупликаций и генных экспансий. К уникальным геномным сегментам относится также мегасателлит DXZ4 на q плече хромосомы X, который также попадает в категорию CpG-островов, порожденных тандемными дупликациями.

CG-rich islands (CpG-islands, or CGI) are important functional elements in a genome of vertebrates. In particular, they: a) initiate transcription as promoters in most (> 50 %) genes of vertebrates, in some cases bi-directional, due to self-complement feature of cg dinucleotides; b) form a global methylation landscape; c) act as a transcription “switch” via methylation. The degenerate nature of CpG-island (elevated CG composition) implies an increase in the probability of tandem repeats and palindromes within CpG- island. This work is devoted to the identification of tandem duplications of complete CpG-islands, i. e. considering mega monomers of size 400–5 000 bp, in the human genome. We found a range of inter- and intragenic tandem duplications of CpG-islands. Intergenic CpGi duplication mediates through CG-rich telomeric satellites, as well as elements of the SINE. One of the most pronounced tandems are located in chromosome 19, known for its abundance of segment duplications and gene expansion. We also underline the unique genomic segment, which is DXZ4 mega satellite, in q arm of chromosome X, also falling into the category of CpG-islands which evolved by tandem duplications rounds.

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The authors declare that there are no conflicts of interest present.