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Photoactivation and inactivation of Arabidopsis cryptochrome 2.

ABSTRACT: Cryptochromes are blue-light receptors that regulate development and the circadian clock in plants and animals. We found that Arabidopsis cryptochrome 2 (CRY2) undergoes blue light-dependent homodimerization to become physiologically active. We identified BIC1 (blue-light inhibitor of cryptochromes 1) as an inhibitor of plant cryptochromes that binds to CRY2 to suppress the blue light-dependent dimerization, photobody formation, phosphorylation, degradation, and physiological activities of CRY2. We hypothesize that regulated dimerization governs homeostasis of the active cryptochromes in plants and other evolutionary lineages.

SUBMITTER: Wang Q

PROVIDER: S-EPMC6180212 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Photoactivation and inactivation of Arabidopsis cryptochrome 2.

Wang Qin Q Zuo Zecheng Z Wang Xu X Gu Lianfeng L Yoshizumi Takeshi T Yang Zhaohe Z Yang Liang L Liu Qing Q Liu Wei W Han Yun-Jeong YJ Kim Jeong-Il JI Liu Bin B Wohlschlegel James A JA Matsui Minami M Oka Yoshito Y Lin Chentao C

Science (New York, N.Y.) 20161001 6310

Cryptochromes are blue-light receptors that regulate development and the circadian clock in plants and animals. We found that Arabidopsis cryptochrome 2 (CRY2) undergoes blue light-dependent homodimerization to become physiologically active. We identified BIC1 (blue-light inhibitor of cryptochromes 1) as an inhibitor of plant cryptochromes that binds to CRY2 to suppress the blue light-dependent dimerization, photobody formation, phosphorylation, degradation, and physiological activities of CRY2. ...[more]

PMID: 27846570

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