GLABROUS INFLORESCENCE STEMS (GIS) is required for trichome branching through gibberellic acid signaling in Arabidopsis.
Cell differentiation generally corresponds to the cell cycle, typically forming a non-dividing cell with a unique differentiated morphology, and Arabidopsis trichome is an excellent model system to study all aspects of cell differentiation. Although gibberellic acid is reported to be involved in trichome branching in Arabidopsis, the mechanism for such signaling is unclear. Here, we demonstrated that GLABROUS INFLORESCENCE STEMS (GIS) is required for the control of trichome branching through gibberellic acid signaling. The phenotypes of a loss-of-function gis mutant and an overexpressor showed that GIS acted as a repressor to control trichome branching. Our results also show that GIS is not required for cell endoreduplication, and our molecular and genetic study results have shown that GIS functions downstream of the key regulator of trichome branching, STICHEL (STI), to control trichome branching through the endoreduplication-independent pathway. Furthermore, our results also suggest that GIS controls trichome branching in Arabidopsis through two different pathways and acts either upstream or downstream of the negative regulator of gibbellic acid signaling SPINDLY (SPY).
Department of Agronomy, College of Agriculture and Biotechnology, Zhejiang University, 866 Yuhangtang Rd, Hangzhou, 310058, PR China.
Lijun
L
An
Zhongjing
Z
Zhou
Sha
S
Su
An
A
Yan
Yinbo
Y
Gan
D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000378:metabolism* / Q000494:pharmacology; D009154:Mutation; D018514:Plant Structures / Q000254:growth & development*; D012097:Repressor Proteins / Q000378:metabolism; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; C512212:GIS protein, Arabidopsis; D005875:Gibberellins; D012097:Repressor Proteins; C101465:SPY protein, Arabidopsis; C474076:STICHEL protein, Arabidopsis; D014157:Transcription Factors; C007842:gibberellic acid