Perego M, Hanstein C, Welsh K M, Djavakhishvili T, Glaser P, Hoch J A
Dipartimento Farmaceutico, Università degli Studi di Parma, Italy.
Cell. 1994 Dec 16;79(6):1047-55. doi: 10.1016/0092-8674(94)90035-3.
The initiation of sporulation in B. subtilis is regulated by the Spo0A transcription factor, which is activated by phosphorylation to control developmental switching from the vegetative to the sporulation state. The level of phosphorylation of Spo0A is regulated by the phosphorelay, a signal transduction system based on the protein-histidine kinase-response regulator two-component paradigm. To initiate sporulation, the cell must recognize and interpret a large variety of environmental, metabolic, and cell cycle signals that influence the phosphorylation level of Spo0A. We describe here a family of protein-aspartate phosphatases with activity on Spo0F approximately P, a response regulator component of the phosphorelay, that provide a mechanism for signal recognition and interpretation. These phosphatases function to drain the phosphorelay, lower Spo0A approximately P levels, and prevent sporulation. The integration of diverse environmental signals that affect the initiation of sporulation likely occurs through the competition between opposing activities of protein kinases and protein phosphatases.
枯草芽孢杆菌中芽孢形成的起始由Spo0A转录因子调控，该转录因子通过磷酸化被激活，以控制从营养态到芽孢形成态的发育转换。Spo0A的磷酸化水平由磷酸传递系统调控，这是一种基于蛋白质-组氨酸激酶-反应调节因子双组分模式的信号转导系统。为了启动芽孢形成，细胞必须识别并解读多种影响Spo0A磷酸化水平的环境、代谢和细胞周期信号。我们在此描述了一类对磷酸传递系统的反应调节因子组分Spo0F∼P具有活性的蛋白质-天冬氨酸磷酸酶家族，它们提供了一种信号识别和解读机制。这些磷酸酶的作用是消耗磷酸传递系统、降低Spo0A∼P水平并阻止芽孢形成。影响芽孢形成起始的多种环境信号的整合可能通过蛋白激酶和蛋白磷酸酶的相反活性之间的竞争而发生。
