MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the Yangtze River, Huazhong Agricultural University, Wuhan 430070, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
College of Life Sciences, South-Central University for Nationalities, Wuhan 430074, China.
J Plant Physiol. 2020 Jun;249:153165. doi: 10.1016/j.jplph.2020.153165. Epub 2020 Apr 28.
Calmodulin-like proteins (CMLs) have been shown to play key regulatory roles in calcium signaling in plants. However, few bona-fide CMLs binding proteins have been characterized in rice, a monocot model plant. Here, through large-scale screening of a yeast-two hybrid (Y2H) cDNA library with OsCML16 as a bait, six new putative interacting partners of OsCML16 were discovered and confirmed by both pairwise Y2H and bimolecular fluorescence complementation (BiFC) assays. Interestingly, the in vitro peptide-binding assays manifested that OsERD2 could bind both OsCaM1 and OsCML16 whereas other five target proteins could specifically bind OsCML16 but not OsCaM1. Furthermore, Ca and TFP, a calmodulin (CaM) antagonist, were involved in the ABA-induced transcription of OsCML16 and its target genes, and they were also obviously induced by cold, drought, and salt stresses. Taken together, our new findings have provided the basis for the novel signaling pathways of OsCML16 in the abiotic stress response in rice.
钙调素样蛋白（CMLs）在植物的钙信号转导中发挥着关键的调节作用。然而，在单子叶模式植物水稻中，仅有少数真正的 CML 结合蛋白被鉴定出来。在这里，我们通过以 OsCML16 为诱饵的大规模酵母双杂交（Y2H）cDNA 文库筛选，发现了六个新的 OsCML16 假定互作伙伴，并通过两两 Y2H 和双分子荧光互补（BiFC）实验进行了验证。有趣的是，体外肽结合实验表明，OsERD2 可以同时结合 OsCaM1 和 OsCML16，而其他五个靶蛋白可以特异性结合 OsCML16 但不结合 OsCaM1。此外，Ca 和 TFP，一种钙调蛋白（CaM）拮抗剂，参与了 ABA 诱导的 OsCML16 及其靶基因的转录，它们也明显受到冷、干旱和盐胁迫的诱导。总之，我们的新发现为水稻非生物胁迫响应中 OsCML16 的新信号通路提供了基础。
