The Potyviral Protein 6K2 from Turnip Mosaic Virus Increases Plant Resilience to Drought

Abstract

Virus infection can increase drought tolerance of infected plants compared to non-infected plants; however, the mechanisms mediating virus-induced drought tolerance remain unclear. In this study, we demonstrate turnip mosaic virus (TuMV) infection increases Arabidopsis thaliana survival under drought compared to uninfected plants. To determine if specific TuMV proteins mediate drought tolerance, we cloned the coding sequence for each of the major viral proteins and generated transgenic A. thaliana that constitutively express each protein. Three TuMV proteins, 6K1, 6K2, and NIa-Pro, enhanced drought tolerance of A. thaliana when expressed constitutively in plants compared to controls. While in control plants drought induced transcripts related to abscisic acid (ABA) biosynthesis and ABA levels, there were no changes in ABA or related transcripts in plants expressing 6K2 under drought conditions compared to well-watered. Expression of 6K2 also conveyed drought tolerance in another host plant, Nicotiana benthamiana, when expressed using a virus over expression construct. In contrast to ABA, 6K2 expression enhanced salicylic acid (SA) accumulation in both Arabidopsis and N. benthamiana. These results suggest 6K2-induced drought tolerance is mediated through increased SA levels, and SA-dependent induction of plant secondary metabolites, osmolytes, and antioxidants that convey drought tolerance.

Silencing ZmPP2C‐A10 with a foxtail mosaic virus (FoMV) derived vector benefits maize growth and development following water limitation

“…2018; Prakash et al . 2023), and more recently, a FoMV virus‐enabled gene editing (VEdGE) vector was also developed for Cas9‐mediated gene editing (Mei et al . 2019).…”

“…2020; Prakash et al . 2023). In brief, plant samples were lyophilized, weighed, then ground to a fine powder.…”

“…2022; Prakash et al . 2023), and the expression of certain viral proteins can increase drought tolerance in host plants (Westwood et al . 2013; Corrales‐Gutierrez et al .…”

“…2020; Prakash et al . 2023). Viruses have also been used as tools to silence different components of the ABA signalling pathway using virus‐induced gene silencing (VIGS) (Manmathan et al .…”

“…2018; Prakash et al . 2023). In this study, FoMV was used to silence ZmPP2C‐A10 in maize, and indicators of drought tolerance were measured in silenced plants.…”