Molecular insights into the role of VRS5 in tillering and lateral spikelet development in barley

In barley, two important agronomic traits are linked on a molecular level, namely: the development of side shoots and row-type, the number of grains on the spike. This is because a protein named VRS5 regulates both of these processes. Manipulating one of these traits independently is difficult because of this molecular link. VRS5 is a transcription factor, meaning that it binds DNA and can regulate the expression of downstream target genes. In one chapter, we identified these target genes during the development of side shoots, and the target genes during development of the spike. In another chapter, we discovered that there are two variants of the VRS5 protein that both function differently. By deleting one of these variants, we were able to untangle the development of side shoots from row-type. With the molecular insights provided in this thesis, I showed several potential ways to help untangle yield-related traits in barley, specifically via VRS5.