Crop Breeding Research Division, Hokkaido Agricultural Research Center, National Agriculture and Food Research Organization, Hitsujigaoka 1, Toyohira-ku, Sapporo, Japan.
Cell Stress Chaperones. 2013 Jul;18(4):517-25. doi: 10.1007/s12192-012-0398-3. Epub 2013 Jan 20.
Arabidopsis COLD SHOCK DOMAIN PROTEIN 3 (AtCSP3) shares an RNA chaperone function with E. coli cold shock proteins and regulates freezing tolerance during cold acclimation. Here, we screened for AtCSP3-interacting proteins using a yeast two-hybrid system and 38 candidate interactors were identified. Sixteen of these were further confirmed in planta interaction between AtCSP3 by a bi-molecular fluorescence complementation assay. We found that AtCSP3 interacts with CONSTANS-LIKE protein 15 and nuclear poly(A)-binding proteins in nuclear speckles. Three 60S ribosomal proteins (RPL26A, RPL40A/UBQ2, and RPL36aB) and the Gar1 RNA-binding protein interacted with AtCSP3 in the nucleolus and nucleoplasm, suggesting that AtCSP3 functions in ribosome biogenesis. Interactions with LOS2/enolase and glycine-rich RNA-binding protein 7 that are cold inducible, and an mRNA decapping protein 5 (DCP5) were observed in the cytoplasm. These data suggest that AtCSP3 participates in multiple complexes that reside in nuclear and cytoplasmic compartments and possibly regulates RNA processing and functioning.
拟南芥冷休克域蛋白 3（AtCSP3）与大肠杆菌冷休克蛋白具有 RNA 伴侣功能，并在冷驯化过程中调节耐冻性。在这里，我们使用酵母双杂交系统筛选了 AtCSP3 的相互作用蛋白，鉴定出 38 个候选相互作用蛋白。其中 16 个通过双分子荧光互补测定在植物体内进一步证实了与 AtCSP3 的相互作用。我们发现 AtCSP3 与核斑中的 CONSTANS-LIKE 蛋白 15 和核 poly(A)-结合蛋白相互作用。三个 60S 核糖体蛋白（RPL26A、RPL40A/UBQ2 和 RPL36aB）和 Gar1 RNA 结合蛋白与 AtCSP3 在核仁及核质中相互作用，表明 AtCSP3 参与核糖体生物发生。在细胞质中观察到与冷诱导的 LOS2/烯醇酶和富含甘氨酸的 RNA 结合蛋白 7 以及 mRNA 去帽蛋白 5（DCP5）的相互作用。这些数据表明，AtCSP3 参与存在于核和细胞质区室中的多个复合物，可能调节 RNA 加工和功能。
