Relative frequency dynamics and loading of beet necrotic yellow vein virus genomic RNAs during the acquisition by its vector Polymyxa betae.

Abstract

Our understanding of the transmission of plant viruses by protozoan vectors remains poor and fragmented. The fate of viral elements in the living stages of the vector is unknown. Here, we first established a protocol allowing the purification of two forms of the vector free of cellular contaminants. This permitted the examination of the relative frequencies of beet necrotic yellow vein virus RNAs in the roots of its natural host and in two forms of its protozoan vector, Polymyxa betae, responsible for virus transmission. Our findings provide new insights into virus behavior during vector transmission, allowing us to analyze how the virus regulates its RNA frequencies and load within the vector. By focusing on the early stages of viral transmission and separating virus acquisition from transmission to new hosts, we pave the way for experiments aimed at elucidating the molecular mechanisms behind viral acquisition and the maintenance of viral genome integrity by P. betae.