Lipid droplets and phytovirus infection

The RAPT (lipid dRoplets And PhyTovirus infection) project undertakes an innovative exploration into the potential role of plant leaf lipid droplets (LDs) in the replication of plant viruses, specifically focusing on plant RNA viruses.

Lipid droplets, which are ubiquitous organelles derived from endoplasmic reticulum (ER) membranes, play key roles in energy production, membrane biogenesis, and stress signalling.

While certain animal RNA viruses utilize LDs for energy or as platforms for viral replication compartments (VRCs), evidence for similar mechanisms in plant RNA viruses remains elusive.

The project builds on the previous observations made by the host lab, which suggest a higher abundance of LDs in turnip mosaic virus (TuMV, potyvirus) infected leaves and their spatial proximity to VRCs.

The hypothesis is that certain plant viruses, like TuMV, utilize LDs as energy reservoirs for their genome replication, potentially facilitating direct interaction with VRCs. To validate and expand upon this hypothesis, the RAPT project is defined into three primary objectives:1. Exploring the impact of plant virus infection on LD distribution and lipid metabolism2.

Functional validation of the involvement of plant LDs in the potyvirus infection cycle3.

Elucidating the molecular mechanisms governing the interactions between LDs and TuMVThese objectives address key knowledge gaps regarding the role of LDs in plant virus infection and will focus on potyviruses, mainly TuMV, but other (+) ssRNA virus species of agroeconomic importance such as luteoviruses and poleroviruses will also be studied, with the aim to expand the findings to crops.

The results of this project will contribute to the development of broad-spectrum genetic resistances that can be harnessed by breeders to mitigate the adverse impacts of plant viral diseases on agricultural productivity.