Exploring the role of potato trithorax proteins (StSDG4 and StATX1) in the de novo shoot regeneration in Nicotiana benthamiana and Arabidopsis thaliana

Abstract

Regeneration is a fundamental characteristic feature that enables plant to propagate, repair, replace tissue, and adapt to the environment. Understanding regeneration is only achievable through elucidating the function of underlying genes and their interplay mechanistically governing the process of differentiation, dedifferentiation, the primary steps of plant regeneration. Preliminary results from the lab show that the two Potato trithorax genes, StSDG4 and StATX1 are involved in regeneration response. This is due to the fact that shoot regeneration efficiency is found to be severely reduced and delayed in Agrobacterium-mediated plant transformation events., a process that is usually quite faster in potato de novo shoot regeneration. In this study, we hypothesize that these trithorax proteins could have conserved functions in other plants. To understand this further, two model plants – Nicotiana benthamiana and Arabidopsis thaliana – were selected for exploring the effects of StSDG4 and StATX1 genes in the de novo shoot regeneration process. In this aspect, overexpression transgenic lines of N. benthamiana were generated through Agrobacterium-mediated plant transformation. During the transformation stage and in the latter regeneration assays, a delayed and less efficient frequency of shoot regeneration is observed in the two overexpression lines in N. benthamiana . Similarly, preliminary experiments in A. thaliana indicated that in the processes of line generation using Agrobacterium mediated plant transformation I have observed a less transformation efficiency for overexpression lines of these two genes as well as these genes having some role in phenotypic traits affecting development. This study brings us one step closer to understanding the mechanism of regeneration and shows that the potato trithorax genes, StSDG4 and StATX1 may have a conserved role in mediating regeneration across species.