title: Arabidopsis FHY3/CPD45 regulates far-red light signaling and chloroplast division in parallel.
abstract: CPD45 (chloroplast division45),which is also known as FHY3 (far-red elongated hypocotyl3), is a key factor in the far-red light signaling pathway in Arabidopsis. We previously showed that FHY3/CPD45 also regulates chloroplast division. Because light is also a regulator of chloroplast development and division, we sought to clarify the relationship between far-red light signaling and chloroplast division pathways. We found that the chloroplast division mutant arc5-3 had no defect in far-red light sensing, and that constitutive overexpression of ARC5 rescued the chloroplast division defect, but not the defect in far-red light signaling, of cpd45. fhy1, which is defective in far-red light signaling, exhibited normal chloroplast division. Constitutive overexpression of FHY1 rescued the far-red light signaling defect, but not the chloroplast division defect, of cpd45. Moreover, ARC5 and FHY1 expression were not affected in fhy1 and arc5-3, respectively. Based on these results, we propose that FHY3/CPD45 regulates far-red light signaling and chloroplast division in parallel by activating the expression of FHY1 and ARC5 independently. This work demonstrates how relationships between different pathways in a gene regulatory network can be explored.
authors: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
authors: Ning
authors: N
authors: Chang
authors: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
authors: Yuefang
authors: Y
authors: Gao
authors: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
authors: Lin
authors: L
authors: Zhao
authors: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
authors: Xiaomin
authors: X
authors: Liu
authors: College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing, 100083, China.
authors: Hongbo
authors: H
authors: Gao
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000378:metabolism*; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D008027:Light; D058503:Mesophyll Cells / Q000502:physiology; D009154:Mutation; D010641:Phenotype; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins