A genetic strategy to uncover the molecular mechanisms of bps signal-induced growth arrest in Arabidopsis

posterWe are studying the bps signaling pathway in Arabidopsis thaliana to find the genetic basis, and molecular mechanism for plant growth arrest, and the goal of my project is to test the roles of 57 up-regulated genes in causing growth arrest. bps1 mutants arrest growth shortly after germination, and the cause of growth arrest is a small molecule, the bps signal, which is over-produced in the roots of bps 1 mutants. This compound induces strong drought-related gene expression in wild-type shoots, and the BPS1 protein is hypothesized to coordinate root and shoot drought responses by regulated synthesis of hte bps signal. The Sieburth lab previously identified 57 genes that are upregulated by bps signal and are candidates for causing growth arrest. To identify which of these 57 genes functions to arrest growth, we are obtaining mutants with defects in these genes, generating double mutants with bps1, and characterizing their phenotypes. Here I describe analysis of At2g29460, which encodes GLUTATHIONE S_TRANSFERASE 22, and I refere to mutants in this gene as gst22. if the up-regulation of GST22 by the bps signal causes growth arrest, then we expect that gst22 single mutants might not show any abnormal phenotype, while the bps1-2 gst22 double mutant would show reduced growth arrest (that is, it would produce leaves). Understanding the mechanism of bps signal-induced growth arrest is an important step in understanding how drought causes its severe reduction in agricultural productivity. Presented at the 2018 ACCESS Symposium at the University of Utah