KMID : 0368420160590060594
|
|
Journal of Plant Biology 2016 Volume.59 No. 6 p.594 ~ p.602
|
|
Suppressor of bri1-120 mutant allele revealed interrelated and independent actions of brassinosteroid and light signaling
|
|
Shang Yun
Fu Minjie Nam Kyoung-Hee
|
|
Abstract
|
|
|
Brassinosteroids (BRs) are plant hormones that affect diverse aspects of plant development. Various BR-biosynthetic or BR-signaling mutants contribute to BR functions and signaling events in many plant species. The BR receptor brassinosteroid-Insensitive 1 (BRI1) plays critical roles in BR signaling. We previously identified a weak bri1 mutant allele, bri1-120, that has a mutation site in the extracellular domain of BRI1. Here, genetic suppressor screening revealed that a PHYB gene mutation led to suppression of ethyl methanesulfonate (EMS)-mutagenized bri1-120. The morphology of bri1-120phyB-1 indicated that compact and rounded phenotypes of bri1-120 were suppressed. However, BR sensitivity of the bri1-120phyB-1 was only recovered in hypocotyl elongation, and overexpression of PHYB in bri1-120 did not enhance bri1-120 phenotypes. To further investigate the relationship between BR and light signalings, we examined the seed germination pattern and hypocotyl growth of bri1-120phyB-1 as compared to that of each single mutant under various light conditions. Seed germination in bri1-120phyB-1 was higher than in both the single mutants. Hypocotyl length in bri1-120phyB-1 was intermediate between that of bri1-120 and phyB-1, whereas sensitivity to red light in bri1-120phyB-1 remained the same as in phyB-1. These results suggest that BR and light signalings affect diverse cellular responses both together and independently, depending on the specific cellular processes.
|
|
KEYWORD
|
|
Brassinosteroid, BRI1, Light, PHYTOCHROME B, Suppressor screening
|
|
FullTexts / Linksout information
|
|
|
|
Listed journal information
|
|
|