Transcription factors controlling biotic stress response in potato plants

Abstract

Plants are constantly exposed to biotic stress factors that affect their growth, development, and productivity. This interaction involves complex molecular mechanisms of resistance, tolerance, susceptibility, and sensibility. Potato is an important crop around the world, not only as a commodity but also as crop model, so to understand its gene regulation is particularly useful. The role of Transcription Factors (TFs) in gene regulation in biotic stress response in potato was not summarized and analyzed in any previous review. In this article, an inventory of potato TFs involved in biotic defenses was retrieved. Nine (ARF, NAC, WRYK, AP2/ERF-ERF, AP2/ERF-DREB, ZFP, TCP, bZIP, and BELL) from 67 TFs families were identified as having a role in defensive responses in potato. Activation/inactivation of such TFs triggers diverse metabolic pathways allowing plants to produce defensive proteins, metabolites, plant hormones, and/or transcriptional and post transcriptional modifications. Also, in this review, the phylogeny of StARF6, StARF17, and StWRKY8 was studied. An alignment and its comparison between amino acid sequences with related and distant species were conducted. As conclusions, our findings suggest divergence by functional approaches since we found they were related to other biotic response genes as well with constitutive genes for growth and development, being necessary to investigate more about homology and orthology to define more accurately response patterns among multiple species. The regulatory mechanisms reported include regulation at the transcriptional level through growth regulators and post-transcriptional regulation through modifications that inactivate or activate the resulting protein. The overexpression and activity depend not only on the number of copies of a gene but also on the elements present in its structure and the interaction/dimerization with other proteins. Synteny studies might be further conducted in potato because most of the evidence is focused on homology between species or emphasis on other Solanaceae. Analyses of potato TFs will help to understand the evolutionary and domestication processes, as well as provide useful knowledge for potato breeding programs aiming biotic stress resistance to increase productivity.