References

vavilov

Вавиловский журнал генетики и селекции

Vavilov Journal of Genetics and Breeding

2500-3259

Institute of Cytology and Genetics of Siberian Branch of the RAS

10.18699/VJ19.542

vavilov-2259

Research Article

Биология развития растений

Developmental biology of plants

Транскриптомный анализ каллусов Medicago truncatula со сверхэкспрессией гена MtWOX9-1

Transcriptomic analysis of Medicago truncatula calli with MtWOX9-1 overexpression

https://orcid.org/0000-0002-0549-1457

Творогова

В. Е.

Tvorogova

V. E.

Санкт-Петербург.

St. Petersbur.

v.tvorogova@spbu.ru

Красноперова

Е. Ю.

Krasnoperova

E. Y.

Санкт-Петербург.

St. Petersbur.

Кудряшов

А. А.

Kudriashov

A. A.

Санкт-Петербург.

St. Petersbur.

Кузнецова

К. А.

Kuznetsova

K. A.

Санкт-Петербург.

St. Petersbur.

Поценковская

Э. А.

Potsenkovskaya

E. A.

Санкт-Петербург.

St. Petersbur.

Федорова

Ю. А.

Fedorova

Y. A.

Санкт-Петербург.

St. Petersbur.

https://orcid.org/0000-0001-6125-0757

Лутова

Л. А.

Lutova

L. A.

Санкт-Петербург.

St. Petersbur.

Санкт-Петербургский государственный университет, кафедра генетики и биотехнологииРоссияSt. Petersburg State University, Department of Genetics and BiotechnologyRussian Federation

2019

10102019

236691699

2019

Творогова В.Е., Красноперова Е.Ю., Кудряшов А.А., Кузнецова К.А., Поценковская Э.А., Федорова Ю.А., Лутова Л.А.

Tvorogova V.E., Krasnoperova E.Y., Kudriashov A.A., Kuznetsova K.A., Potsenkovskaya E.A., Fedorova Y.A., Lutova L.A.

This work is licensed under a Creative Commons Attribution 4.0 License.

https://vavilov.elpub.ru/jour/article/view/2259

Соматический эмбриогенез (СЭ) – это развитие зародышеподобных структур из соматических тканей растений. Этот процесс редко можно наблюдать в природе, однако для многих видов растений разработаны протоколы культивирования в условиях in vitro, с помощью которых можно добиться формирования соматических эмбрионов напрямую из тканей растительного экспланта или из эмбриогенного каллуса. СЭ широко применяют в биотехнологии для размножения и трансформации растений, и в связи с этим поиск стимуляторов СЭ и изучение механизмов их работы представляют собой актуальную задачу. Белки WOX играют важную роль в регуляции СЭ. WOX (WUSCHEL-RELATED HOMEOBOX) – семейство гомеодомен-содержащих транскрипционных факторов. Различные гены WOX функционируют в разных органах и тканях растений, поддерживая активность меристем и регулируя пролиферацию и дифференцировку клеток. Ранее нами было обнаружено, что транскрипционный фактор MtWOX9-1, принадлежащий к семейству WOX, способен стимулировать соматический эмбриогенез в каллусной культуре у Medicago truncatula. В настоящем исследовании проведен сравнительный анализ транскриптома высокоэмбриогенных каллусов со сверхэкспрессией гена MtWOX9-1 и транскриптома каллусов дикого типа. Показано, что сверхэкспрессия MtWOX9-1 вызывает активацию нескольких групп генов, включая гены, связанные с делением клеток, дифференцировкой тканей, а также с развитием семян. Среди обогащенных наборов генов в терминах GO мы обнаружили несколько групп с активностью метилтрансфераз гистонов, метилированием ДНК и связыванием с хроматином, что предполагает существенные эпигенетические изменения, происходящие в каллусах со сверхэкспрессией MtWOX9-1. Используя базу данных Medicago Truncatula Gene Expression Atlas, мы идентифицировали также группу генов, кодирующих транскрипционные факторы, которые коэкспрессируются с MtWOX9-1 в различных органах растений и характеризуются дифференциальной экспрессией в наших образцах. Эти гены представляют собой предполагаемые мишени MtWOX9-1, которые могут работать в одном пути с этим регулятором в ходе СЭ.

Somatic embryogenesis (SE) is the development of embryo-like structures from somatic plant tissues. This process rarely can be observed in nature, but for many plant species, in vitro protocols are developed, which allow to obtain somatic embryos formation directly from tissues of plant explant or from the embryogenic callus. SE is widely used for plant propagation and transformation; therefore, the search for SE stimulators and revealing of the mechanisms of their functioning are very important for biotechnology. Among the SE regulators, proteins of the WOX family play significant roles. WOX (WUSCHEL-RELATED HOMEOBOX) is a homeodomain-containing transcription factor family. Different WOX genes function in different plant organs and tissues, maintaining meristem activity and regulating cell proliferation and differentiation. Recently, we have shown that transcription factor MtWOX9-1, belonging to the WOX family, can stimulate SE in the Medicago truncatula callus culture. In this research, transcriptomic analysis of highly embryogenic calli with MtWOX9-1 overexpression was performed in comparison to wildtype calli. It was shown that MtWOX9-1 overexpression led to the activation of several groups of genes, including genes related to cell division, tissue differentiation, and seed development. Enriched GO pathways included several groups related to histone methyltransferase activity as well as DNA methylation and chromatin binding, suggesting major epigenetic changes that occur in call overexpressing MtWOX9-1. Using Medicago Truncatula Gene Expression Atlas, we also identified a group of genes coding for transcription factors that were both coexpressed with MtWOX9-1 in different plant organs and differentially expressed in our samples. These genes are putative targets of MtWOX9-1, and they may act in the same pathway with this regulator during SE.

соматический эмбриогенезMedicago truncatulaрегенерация растенийтранскрипционные факторытранскриптомный анализ

somatic embryogenesisMedicago truncatulaplant regenerationtranscription factorstranscriptomic analysis

This work was supported by Russian Scientific Foundation project No. 16-16-10011, the grant from Russian Foundation for Basic Research No. 17-04-01708 and the grant of SPbU Alumni Association. We thank Million Tadege, Tezera W. Wolabu and Fei Zhang for providing seeds of w9o plants and Zengyu Wang for providing R-108 seeds. We are also grateful to all the teachers of Bioinformatics Institute (St. Petersburg, Russia) for gained knowledge and skills and Andrew Matveenko for discussing the data in the process of preparing this paper.

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