拟南芥(Arabidopsis thaliana)蛋白UVR8(UV RESISTANCE LOCUS 8)是UV-B特异的光受体, 介导UV-B诱导的光形态建成。无UV-B照射时, UVR8以二聚体的形式存在于细胞质和细胞核中。接收到UV-B光信号后, 细胞质中的UVR8转移到细胞核中并解聚, 之后与E3泛素连接酶COP1(CONSTITUTIVELY PHOTOMORPHOGENIC 1)相互作用, 调节一系列重要的UV防御基因的表达。UVR8除了作为UV-B特异的光受体, 在细胞中也具有重要作用, 协调整个植物体对UV-B的应答。该文重点综述了UVR8蛋白的结构、生理功能及其介导的UV-B光信号转导分子机制等方面的研究进展。

The Arabidopsis thaliana protein UVR8 is a photoreceptor for ultraviolet-B, mediating UV-B-induced photomorphogenesis. Under light conditions devoid of UV-B, UVR8 is localized in both the cytoplasm and nucleus as homodimers. Absorption of UV-B promotes the nuclear accumulation and instant monomerization of the photoreceptor, then interacts with CONSTITUTIVELY PHOTOMORPHOGENIC 1 to orchestrate a series of genes essential for UV-B protection. Besides being a UV-B-specific photoreceptor, UVR8 plays an important role in the cell to mediate the whole-plant UV-B response. This review focuses on recent understandings of the structure and physiological function of UVR8 and molecular mechanism of UVR8-mediated UV-B signal transduction.