Lomin S N, Savelieva E M, Elanskaya A S, Arkhipov D V, Romanov G A
Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, Russia.
Dokl Biochem Biophys. 2025 Jun 2. doi: 10.1134/S1607672925600381.
Bioinformatic methods have been used to predict a new subclass of proteins among plant phosphotransmitters involved in the signaling system of multistep phosphorelay. In contrast to the canonical soluble nucleocytosolic forms, the found noncanonical phosphotransmitter sequences, belonging to a wide range of plant taxa, potentially contain transmembrane domains. This suggests localization of such proteins on cell membranes and, therefore, a different function in signaling than that of canonical phosphotransmitters. We tested the functionality of the transmembrane domain of the phosphotransmitter using the protein of the tea plant Camellia sinensis. The membrane localization of the transiently expressed recombinant phosphotransmitter with this domain was confirmed by microscopy and immunoblotting. Thus, this is the first study to obtain experimental evidence for the existence of membrane-bound plant phosphotransmitters with as yet unknown functions. These data suggest the presence of a noncanonical membrane branch of signal transduction in the multistep phosphorelay system in plants.
生物信息学方法已被用于预测参与多步磷酸化信号系统的植物磷酸传递体中的一类新蛋白质亚类。与典型的可溶性核质形式不同，发现的属于多种植物类群的非典型磷酸传递体序列可能含有跨膜结构域。这表明此类蛋白质定位于细胞膜上，因此在信号传导中的功能与典型磷酸传递体不同。我们使用茶树的蛋白质测试了磷酸传递体跨膜结构域的功能。通过显微镜和免疫印迹证实了带有该结构域的瞬时表达重组磷酸传递体的膜定位。因此，这是第一项获得关于具有未知功能的膜结合植物磷酸传递体存在的实验证据的研究。这些数据表明植物多步磷酸化信号系统中存在非典型的膜信号转导分支。
