vavilovВавиловский журнал генетики и селекцииVavilov Journal of Genetics and Breeding2500-3259Institute of Cytology and Genetics of Siberian Branch of the RAS10.18699/VJ17.242vavilov-936Research ArticleГЕНЕТИКА РАСТЕНИЙPLANT GENETICSГомеобоксные гены факторов транскрипции WOX в паразитическом растении Monotropa hypopitys на стадии цветенияHomeobox genes encoding WOX transcription factors in the flowering parasitic plant Monotropa hypopitysЩенниковаА. В.ShchennikovaA. V.

Москва

Moscow

shchennikova@yandex.ruШульгаО. А.ShulgaO. A.

Москва

Moscow

КочиеваЕ. З.KochievaE. Z.

Москва

Moscow

БелецкийА. В.BeletskyA. V.

Москва

Moscow

ФилюшинМ. А.FilyushinM. A.

Москва

Moscow

РавинН. В.RavinN. V.

Москва

Moscow

СкрябинК. Г.SkryabinK. G.

Москва

Moscow

Федеральное государственное учреждение «Федеральный исследовательский центр ”Фундаментальные основы биотехнологии” Российской академии наук», Институт биоинженерииРоссияInstitute of Bioengineering, Research Center of Biotechnology RASRussian Federation201722042017212234240Copyright © Щенникова А.В., Шульга О.А., Кочиева Е.З., Белецкий А.В., Филюшин М.А., Равин Н.В., Скрябин К.Г., 20172017Щенникова А.В., Шульга О.А., Кочиева Е.З., Белецкий А.В., Филюшин М.А., Равин Н.В., Скрябин К.Г.Shchennikova A.V., Shulga O.A., Kochieva E.Z., Beletsky A.V., Filyushin M.A., Ravin N.V., Skryabin K.G.This work is licensed under a Creative Commons Attribution 4.0 License.https://vavilov.elpub.ru/jour/article/view/936

Формирование и поддержание популяций стволовых клеток растения контролируются гомеодомен-содержащими факторами транскрипции семейства WOX. Эволюция гомеобоксных генов, кодирующих данные белки, считается одной из главных причин многообразия форм цветка и морфологии растения в целом. Механизм регуляции ниш стволовых клеток в апикальных меристемах признан консервативным для цветковых растений разных видов и наиболее подробно исследован на модели Arabidopsis thaliana. Морфологическое разнообразие покрытосеменных подразумевает наличие особенностей этого механизма, присущих отдельным видам, при сохранении основных сигнальных путей. Уникальный представитель покрытосеменных бесхлорофилльный микогетеротроф подъельник Monotropa hypopitys получает питательные вещества от корней деревьев через микоризный симбиоз. В индуктивных условиях адвентивные репродуктивные почки на корнях M. hypopitys выпускают цветонос с прицветниками и соцветием на конце. M. hypopitys так же, как и другие растения, формирует меристемы соцветия, цветка и корня, вероятно, используя консервативные пути регуляции ниш стволовых клеток. Изучение гомеобоксных генов такого растения расширит знания о важных эволюционных факторах транскрипции WOX и позволит лучше представлять механизмы контроля стволовых клеток в микогетеротрофных растениях. В данной работе проведен анализ транскриптомов корня, прицветников и цветков двух индивидуальных образцов подъельника, собранных на стадии цветения. Идентифицированы мРНК пяти генов семейства WOX, охарактеризованы их структура, филогения, паттерн экспрессии, а также возможные функции. Совокупность полученных и литературных данных по- зволила сделать предположения о функциональной роли данных генов в онтогенезе растения. Гены MhyWUS1 и MhyWUS2, возмож- но, вовлечены в поддержание популяции стволовых клеток меристем цветка и соцветия. Ген MhyWOX13, вероятно, участвует в контроле корневой ниши стволовых клеток, формировании семенной коробочки, инициации цветения и базовых клеточных процессах. Область применения генов MhyWOX4 и MhyWOX2, видимо, ограничена регуляцией стволовых клеток камбия и дифференцировкой яйцеклеток и зиготы соответственно.

The formation and maintenance of plant stem cell populations are controlled by the WOX family of homeobox-containing transcription factors. The evolution of WOX genes is considered to be one of the main reasons for flower morphology and plant architecture diversity. The stem cell regulation mechanism is considered to be conserved among flowering plants and most thoroughly studied in Arabidopsis thaliana as a model. The angiosperms morphological diversity implies that there are species-specific features inherent to this mechanism, while the basic signaling is maintained. The unique flowering achlorophyllous mycoheterotrophic plant Monotropa hypopitys obtains nutrients from the tree roots through the mycorrhizal symbiosis. In inductive conditions, the reproductive stem with bracts and an inflorescence at the top is developed from an adventitious root bud. Like other plants, M. hypopitys forms the inflorescence, flower and root meristems, presumably using conserved mechanisms regulating stem cell niche. The study of M. hypopitys homeobox genes should contribute to the knowledge about the function of WOX transcription factors and further understanding of the stem cells control mechanisms in mycoheterotrophic species. The aim of the present study was to analyze M. hypopitys root, bracts and flower transcriptomes obtained from two individual flowering plants. In total, five WOX genes have been identified and characterized by their structure, phylogeny, expression pattern, and possible functions. The assumption is that the MhyWUS1 and MhyWUS2 genes maintain the stem cell population in the inflorescence and flower meristems, MhyWOX13 has a role in the control of root stem cell niche, seed pod formation, flowering initiation, and basic cellular processes, MhyWOX4 functions in the control of cambium stem cells, and MhyWOX2 participates in the differentiation of egg cells and zygotes.

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