TCP2 positively regulates HY5/HYH and photomorphogenesis in Arabidopsis
نویسندگان
چکیده
Light regulates plant growth and development via multiple photoreceptors including phytochromes and cryptochromes. Although the functions of photoreceptors have been studied extensively, questions remain regarding the involvement of cryptochromes in photomorphogenesis. In this study, we identified a protein, TEOSINTE-LIKE1, CYCLOIDEA, and PROLIFERATING CELL FACTOR 2 (TCP2), which interacts with the cryptochrome 1 (CRY1) protein in yeast and plant cells via the N-terminal domains of both proteins. Transgenic plants overexpressing TCP2 displayed a light-dependent short hypocotyl phenotype, especially in response to blue light. Moreover, light affected TCP2 expression in a wavelength-dependent manner and TCP2 positively regulates mRNA expression of HYH and HY5. These results support the hypothesis that TCP2 is a transcription activator which acts downstream of multiple photoreceptors, including CRY1.
منابع مشابه
Two interacting bZIP proteins are direct targets of COP1-mediated control of light-dependent gene expression in Arabidopsis.
Arabidopsis COP1 acts to repress photomorphogenesis in the absence of light. It was shown that in the dark, COP1 directly interacts with the bZIP transcription factor HY5, a positive regulator of photomorphogenesis, and promotes its proteasome-mediated degradation. Here we identify a novel bZIP protein HYH, as a new target of COP1. We identify a physical and genetic interaction between HYH and ...
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