Somatic embryogenesis (SE) is one of the plant regeneration pathways. This process is very similar to zygotic embryogenesis, but embryos develop not from zygote, but from vegetative tissues. This process is widely used in biotechnology for plant transformation and propagation. Somatic embryos can derive directly from the vegetative tissues or through the formation of callus. The search for SE stimulators is very important for plant biotechnology.
Several genes were reported to be the regulators of this process, among them the WOX (WUSCHEL-RELATED HOMEOBOX) family members are presented. These genes encode homeodomain-containing transcription factors, participating in different developmental processes. WOX2 is known for its participation in zygotic embryogenesis. It is expressed in the zygote and later in the apical domain of the embryo. We study the role of this gene in the somatic embryogenesis. Overexpression of MtWOX2 in some cases leads to the development of embryogenic calli with increased size. We performed transcriptome analysis of Medicago truncatula calli with overexpression of this gene compared to the calli overexpressing GUS.
It was shown that MtWOX2 overexpression led to the changes in expression levels of genes, enriched with several GO pathways, including groups related to oxidative stress and ROS formation, response to toxic substance and auxin-activated signaling pathway. Among differentially expressed genes there are members of several TF families, e.g. MADS-box, BHLH, MYB, bZIP and others. These genes may regulate embryogenic callus development. Together, these results can be used for the search of new morphogenic regulators applicable for plant transformation.
The research was supported by RFBR grant 20-016-00124.
Plant organisms are the objects of green biotechnology, which have been used by humans in various areas of life. The family of legumes (Fabaceae) that is being studied in this work is not an exception here. It is a very diverse family widespread throughout the globe.
Barrel medic (Medicago truncatula) and common pea (Pisum sativum), members of the legume family, were selected in this study for the development of an vital imaging system for transgenic tissues. As a part of the work, we tested an imaging system with post-mortem staining based on the GUS reporter, as well as a system for vital detection of transgenic tissue with fluorescent proteins GFP and DsRed. At this stage, vital imaging systems based on betalain and anthocyanin staining of transgenic tissues are designed and currently being adapted to the model objects under study.
The results of this study may be useful for subsequent attempts to solve the problem of the low efficiency of transformation of P. sativum. Moreover, such a system should be useful in the study of gene regulatory networks and factors that regulate the process of induction and subsequent development of somatic embryos. In addition, it can be used to track the dynamics of expression of genes of interest on living objects, while studying other fundamental and biotechnological processes.
The study is supported by the Russian Foundation for Basic Research (20-016-00124).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.