AtDOF5.4/OBP4, a DOF Transcription Factor Gene that Negatively Regulates Cell Cycle Progression and Cell Expansion in Arabidopsis thaliana.
In contrast to animals, plant development involves continuous organ formation, which requires strict regulation of cell proliferation. The core cell cycle machinery is conserved across plants and animals, but plants have developed new mechanisms that precisely regulate cell proliferation in response to internal and external stimuli. Here, we report that the DOF transcription factor OBP4 negatively regulates cell proliferation and expansion. OBP4 is a nuclear protein. Constitutive and inducible overexpression of OBP4 reduced the cell size and number, resulting in dwarf plants. Inducible overexpression of OBP4 in Arabidopsis also promoted early endocycle onset and inhibited cell expansion, while inducible overexpression of OBP4 fused to the VP16 activation domain in Arabidopsis delayed endocycle onset and promoted plant growth. Furthermore, gene expression analysis showed that cell cycle regulators and cell wall expansion factors were largely down-regulated in the OBP4 overexpression lines. Short-term inducible analysis coupled with in vivo ChIP assays indicated that OBP4 targets the CyclinB1;1, CDKB1;1 and XTH genes. These results strongly suggest that OBP4 is a negative regulator of cell cycle progression and cell growth. These findings increase our understanding of the transcriptional regulation of the cell cycle in plants.
Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Rd, Shanghai 200032, China.
Peipei
P
Xu
Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Rd, Shanghai 200032, China.
Haiying
H
Chen
Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Rd, Shanghai 200032, China.
Lu
L
Ying
Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Rd, Shanghai 200032, China.
Weiming
W
Cai
D017360:Arabidopsis / Q000166:cytology* / Q000187:drug effects / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects / Q000235:genetics*; D049109:Cell Proliferation / Q000187:drug effects; D047369:Chromatin Immunoprecipitation; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology; D005434:Flow Cytometry; D016195:G2 Phase / Q000187:drug effects / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant; D008938:Mitosis / Q000187:drug effects / Q000235:genetics; D008954:Models, Biological; D005810:Multigene Family; D010641:Phenotype; D010802:Phylogeny; D030821:Plants, Genetically Modified; D021381:Protein Transport / Q000187:drug effects; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism
D029681:Arabidopsis Proteins; D004268:DNA-Binding Proteins; C000623373:OBP4 protein, Arabidopsis; D004958:Estradiol