ovoshchiОвощи РоссииVegetable crops of Russia2072-91462618-7132Федеральный научный центр овощеводства10.18619/2072-9146-2020-6-51-57ovoshchi-1185Research ArticleСЕЛЕКЦИЯ И СЕМЕНОВОДСТВО СЕЛЬСКОХОЗЯЙСТВЕННЫХ РАСТЕНИЙBREEDING AND SEED PRODUCTION OF AGRICULTURAL CROPSКонформационная изменчивость двойных спиралей ДНКConformational variability of DNA double helixhttps://orcid.org/0000-0002-1134-0292ЧесноковЮ. В.ChesnokovYu. V.

Юрий Валентинович Чесноков – доктор биол. наук, директор ФГБНУ АФИ 

Гражданский пр-т, д.14, г. Санкт-Петербург, 195220

Yuriy V. Chesnokov – Doc. Sci. (Biology), Director of Agrophysical Research Institute

14, Grazhdanskiy ave., St.-Petersburg, 195220

yuv_chesnokov@agrophys.ruФедеральное государственное бюджетное научное учреждение «Агрофизический научно-исследовательский институт»РоссияAgrophysical Research InstituteRussian Federation202026122020065157Copyright © Чесноков Ю.В., 20202020Чесноков Ю.В.Chesnokov Y.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.vegetables.su/jour/article/view/1185

Дезоксирибонуклеиновая кислота (ДНК) является одним из основных носителей наследственной информации. Структурная физико-химическая информация ДНК определяет в конечном счете строение и функционирование всех живых организмов. В ДНК же накапливаются разнообразные мутационные и происходят рекомбинационные события, которые приводят к изменчивости организмов и подлежат как естественному, так и искусственному отбору. Взаимодействие «генотип-среда» присущее всем живым организмам свойственно и ДНК, которая находится во внутриклеточном и внутриядерном физико-химическом окружении молекул воды, сахаров, ионов металлов, рН, нуклеотидов и других компонентов. Установление и изучение физико-химических свойств нативной ДНК способствует не только пониманию механизмов строения основной наследственной биомолекулы, но и выяснить их функционирование, а также взаимодействие с другими молекулами на молекулярном уровне. Обнаружение разнообразных форм двойных спиралей: A, Aʹ, B, α-Bʹ, β-Bʹ, C, Cʹ, Cʹʹ, D, E и Z наталкивает на мысль о молекулярно-генетическом разнообразии существующем на уровне ДНК и установление их структурно-функциональных особенностей способно привести к пониманию реализации генетической информации на общебиологическом уровне. Структура природных ДНК в целом, по-видимому, не зависит от последовательности и нуклеотидного состава. Для природных молекул - сателлитных ДНК с повторами или ДНК без повторов, подтверждено наличие только А-, В- и С-форм. Структура ДНК зависит не только от температуры, но и от природы присутствующих катионов. Наличие в среде определенного количества ионов металлов может приводить к переходу В-формы ДНК в Z-форму. В ↔ Zпереход модифицирует общую структуру ДНК, а, следовательно, может оказаться важным для регуляции генной экспрессии. Изучение биологической роли Z-ДНК возможно в ближайшем будущем поможет понять механизм экспрессии генов, прежде всего эпигенетического характера, который до конца пока еще не выяснен.

Deoxyribonucleic acid (DNA) is one of the main carriers of hereditary information. The structural physicochemical information of DNA ultimately determines the structure and functioning of all living organisms. In DNA, various mutational events accumulate and recombination events occur, which lead to the variability of organisms and are subject to both natural and artificial selection. The interaction "genotype-environment" inherent in all living organisms is also characteristic of DNA, which is located in the intracellular and intranuclear physicochemical environment of water molecules, sugars, metal ions, pH, nucleotides and other components. The establishment and study of the physicochemical properties of native DNA contributes to not only understanding the mechanisms of the structure of the main hereditary biomolecule, but also to clarify their functioning, as well as interaction with other molecules at the molecular level. The discovery of various forms of double helices: A, Aʹ, B, α-Bʹ, β-Bʹ, C, Cʹ, Cʹʹ, D, E and Z suggests the idea of molecular genetic diversity existing at the DNA level and the establishment of their structural and functional features can lead to an understanding of the implementation of genetic information at the general biological level. The structure of natural DNA as a whole, apparently, does not depend on the sequence and nucleotide composition. For natural molecules - satellite DNA with repeats or DNA without repeats, the presence of only A-, B- and C-forms has been confirmed. The structure of DNA depends not only on temperature, but also on the nature of the cations present. The presence of a certain amount of metal ions in the medium can lead to the transition of the B-form of DNA to the Zform. The B ↔ Z transition modifies the general structure of DNA and, therefore, may be important for the regulation of gene expression. The study of the biological role of Z-DNA, possibly in the near future, will help to understand the mechanism of gene expression, primarily of an epigenetic nature, which has not yet been fully elucidated.

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