近期，福建农林大学王琴教授课题组在Molecular plant 发表了题为Photooligomerization Determines Photosensitivity and Photoreactivity of Plant Cryptochromes 的研究论文，文章揭示了植物隐花色素早期光反应机制。

植物和非植物物种具有隐色素（cryptochrome，CRY）光受体，介导蓝光对发育或生物钟的调节。蓝光依赖性的拟南芥CRY2同源多聚化是其功能所必需的早期光反应，但光生物化学和光依赖性的隐色素同源多聚化和异源多聚化（统称为CRY光多聚化）的功能尚未得到很好的证实。

本文中，作者证明光多聚化是植物和一些非植物物种中CRY光受体的一种进化保守的光反应特性。作者对拟南芥CRY1和CRY2光多聚化的正、反反应动力学的分析提供了一个先前未被认识的机制，揭示了这两个密切相关的光受体不同的感光性和光活性。作者发现隐花色素的多聚化是其功能的必要但非充分条件。由此推测隐花色素多聚化后可能还存在进一步构象变化以改变隐花色素与其它蛋白的相互作用从而发挥其正常的生理生化功能。作者进一步证明了CRY2–CRY1异源多聚化在拟南芥体内CRYs的功能有调节作用。

综上所述，这些结果表明光多聚化是进化上保守的机制，决定了植物CRYs光敏性和光活性。

Photooligomerization Is Necessary but Not Sufficient for CRY2 Function

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ABSTRACT

Plant and non-plant species possess cryptochrome (CRY) photoreceptors to mediate blue light regulation of development or the circadian clock. The blue light-dependent homooligomerization of Arabidopsis CRY2 is a known early photoreaction necessary for its functions, but the photobiochemistry and function of light-dependent homooligomerization and heterooligomerization of cryptochromes, collectively referred to as CRY photooligomerization, have not been well established. Here, we show that photooligomerization is an evolutionarily conserved photoreaction characteristic of CRY photoreceptors in plants and some non-plant species. Our analyses of the kinetics of the forward and reverse reactions of photooligomerization of Arabidopsis CRY1 and CRY2 provide a previously unrecognized mechanism underlying the different photosensitivity and photoreactivity of these two closely related photoreceptors. We found that photooligomerization is necessary but not sufficient for the functions of CRY2, implying that CRY photooligomerization is presumably accompanied by additional function-empowering conformational changes. We further demonstrated that the CRY2–CRY1 heterooligomerization plays roles in regulating functions of Arabidopsis CRYs in vivo. Taken together, these results suggest that photooligomerization is an evolutionarily conserved mechanism determining the photosensitivity and photoreactivity of plant CRYs.

文章链接：https://doi.org/10.1016/j.molp.2020.01.002