Isolation and characterization of regulators involved in PHOT1-mediated inhibition of hypocotyl phototropism in Arabidopsis

• Published in: Biológia Vol. 72; no. 6; pp. 601 - 607
• Main Authors: Zhao, Qing-Ping, Zhao, Xiang, Zhu, Zi-Yi, Guo, Xi-ning, Li, Nan-Nan, Zhang, Xiao
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.06.2017; De Gruyter Open; Springer Nature B.V
• Subjects: Cell Biology; EMS mutagenesis; Hypocotyls; hypocotyls phototropism; Life Sciences; Luminous intensity; map-based cloning; Microbiology; Mutagenesis; Mutants; Phenotypes; Phot1; Phototropism; Plant Sciences; Redundancy; Regulators; Zoology; EMS mutagenesis; map-based cloning; Phot1; hypocotyls phototropism
• ISSN: 0006-3088; 1336-9563
• DOI: 10.1515/biolog-2017-0070

Blue light receptor phot1 and phot2 regulate hypocotyl phototropism induced by high intensity blue light (HBL) in functional redundancy. The phenotype of rpt2 single mutant is similar with double mutant phot1phot2 that lost phototropism, but rpt2phot1 double mutant shows normal phototropic response, which indicating that phot1 has dual opposite function with inducing and inhibiting hypocotyls phototropism. However, the mechanism of phot1-mediated inhibition remains to be elucidated. Here, we screened mutants with phototropism from EMS mutagenesis of rpt2 and cloned the gene P1SA1 ( underlineP hototropin underline1 underlineS ignaling underlineA ssociated underline1 ), which maybe locate downstream of phot1 and function in regulating phot1-mediated inhibitory response. The rpt2 p1sa1 mutant shows normal phototropism to unilateral HBL and overexpression of PHOT1 in rpt2 p1sa1 lost hypocotyl phototropism again, which indicated that P1SA1 may be the allelic of PHOT1 . These results will open new perspectives about the screening and identification of genes involved in phot1-mediated inhibitory response, and provide theoretical basis for the self-regulation mechanism of plant to reduce high light damage.