vavilovВавиловский журнал генетики и селекцииVavilov Journal of Genetics and Breeding2500-3259Institute of Cytology and Genetics of Siberian Branch of the RAS10.18699/VJ19.521vavilov-2201Research ArticleАКТУАЛЬНЫЕ ТЕХНОЛОГИИMAINSTREAM TECHNOLOGIESБиотехнологические основы получения клонированных эмбрионов свинейBiotechnological bases of the development of cloned pig embryoshttps://orcid.org/0000-0002-1284-1486ЛопуховА. В.LopukhovA. V.vubi_myaso@mail.ruhttps://orcid.org/0000-0003-0198-9757СингинаГ. Н.SinginaG. N.https://orcid.org/0000-0003-4017-6863ЗиновьеваН. А.ZinovievaN. A.Федеральный научный центр животноводства – ВИЖ им. академика Л.К. ЭрнстаРоссияFederal Science Center for Animal Husbandry named after Academy Member L.K. ErnstRussian Federation201922082019235527533Copyright © Лопухов А.В., Сингина Г.Н., Зиновьева Н.А., 20192019Лопухов А.В., Сингина Г.Н., Зиновьева Н.А.Lopukhov A.V., Singina G.N., Zinovieva N.A.This work is licensed under a Creative Commons Attribution 4.0 License.https://vavilov.elpub.ru/jour/article/view/2201

Термин «клон» в биотехнологии животных обозначает организм, полученный в результате неполового размножения, который одновременно является прямым потомком и генетической копией родительского организма. На сегодняшний день домашняя свинья (Sus scrofa domestica) представляется наиболее интересным объектом в исследованиях по клонированию. Клонирование свиней имеет широкий спектр потенциальных возможностей использования в различных областях научной и хозяйственной деятельности человека. Тем не менее эффективность получения клонированных эмбрионов свиней все еще остается ниже, чем других видов сельскохозяйственных животных, в частности лошадей и крупного рогатого скота. Соматическое клонирование – сложная многоступенчатая технология, на каждом этапе которой более восприимчивые к изменениям окружающих условий ооциты свиней испытывают неблагоприятные воздействия различных по своей природе факторов (механические, физические, химические). На этапе созревания ооцитов происходят изменения клеточных ультраструктур ооплазмы, которые играют важную роль в последующем репрограммировании ядра пересаженной донорской клетки. Донорские соматические клетки перед переносом в ооцит синхронизируют в стадии G0/G1 клеточного цикла с целью обеспечения нормальной плоидности клонированного эмбриона. При удалении ядра у созревших in vitro ооцитов свиней следует обращать внимание на проблему сохранения жизнеспособности клеток после извлечения собственного ядерного материала. В ходе реконструирования соматическую клетку с помощью микроинструментов помещают в перивителлиновое пространство, где ранее находилось первое полярное тельце, или в цитоплазму энуклеированного ооцита. Метод ручного клонирования (handmade cloning) предполагает удаление ядра ооцита с последующим слиянием с донорской клеткой без помощи микроманипуляционной техники. Повышенная чувствительность ооцитов к факторам окружающей среды обусловливает особые требования к выбору системы in vitro культивирования клонированных эмбрионов свиней. В рамках настоящего обзора проведен мониторинг современных методов, используемых при получении клонированных эмбрионов, выявлены технологические особенности, препятствующие повышению эффективности метода соматического клонирования свиней.

The term ‘clone’ in animal biotechnology refers to an organism derived from non-sexual reproduction, which is both a direct offspring and a genetic copy of the parent organism. To date, the pig appears to be the most interesting object in cloning research. Somatic cell nuclear transfer in pigs has a wide range of potential applications in various fields of human scientific and economic activities. However, the efficiency of producing cloned embryos in swine is still lower than that of other livestock species, in particular horses and cattle. Somatic cell nuclear transfer is a technically complex multi-stage technology, at each stage of which the pig oocytes, which are more susceptible to changes of surrounding conditions, are affected by various factors (mechanical, physical, chemical). At the stage of oocyte maturation, changes in the cell ultrastructures of the ooplasm occur, which play an important role in the subsequent nuclear reprogramming of the transferred donor cell. Before transfer to the oocyte donor somatic cells are synchronized in the G0/G1 stage of the cell cycle to ensure the normal ploidy of the cloned embryo. When removing the nucleus of pig oocytes maturated in vitro, it is necessary to pay attention to the problem of preserving the viability of cells, which were devoid of their own nuclear material. To perform the reconstruction, a somatic cell is placed, using micro-tools, in the perivitelline space, where the first polar body was previously located, or in the cytoplasm of an enucleated oocyte. The method of manual cloning involves the removal of the oocyte nucleus with subsequent fusion with the donor cell without the use of micromanipulation techniques. The increased sensitivity of oocytes to the environmental conditions causes special requirements for the choice of the system for in vitro culture of cloned pig embryos. In this work, we have reviewed the modern methods used for the production of cloned embryos and identified the technological issues that prevent improving the efficiency of somatic cloning of pigs.

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