630 / 2019-04-26 13:33:30

Identification of Regulators of WOX7 Involved in Sugar-Mediated Lateral Root Development in Arabidopsis thaliana

WOX7,Lateral root,sugar

Growth and Development > Growth and Development

Lateral root (LR) plays a pivotal role in acquisition of nutrient and water, as well as anchoring and mechanical fixation. High sucrose to nitrogen ratio has an inhibiting effect on LR initiation. However, the molecule mechanisms of sugar-dependent regulation of LR development are unclear. Previously we showed that the WUSCHEL related homeobox protein WOX7 repressed LR formation in a sugar-dependent manner, thus providing a new direction to dissect the sugar- mediated root developmental pathway. To this end, we have taken two independent approaches: 1) Check the relationships between WOX7 and existing sugar signaling mutants. 2) Genetic screening for mutations that affect WOX7 expression. EMS-mutagenized mutants were generated in a transgenic line harboring the WOX7pro::GFP construct. Two groups of mutants are expected, with increased or attenuated GFP expression. Three recessive mutants were isolated, which showed increased GFP expression in lateral root primordial (LRP) and a reduced number of LRs. Two mutants also showed short primary roots and more LRPs. Through simple sequence length polymorphism marker analyses, we have mapped the causal mutations for these two mutants to a 3 Mb region in chromosomes 2. Candidate genes with the causal mutations have also been identified by whole genome resequencing and are currently being characterized. This work will significantly enhance the understanding of the mechanisms that control LR formation in plants.