Phosphorylation and dephosphorylation reactions in stomatal guard cells of blue light signaling

点击翻译按钮获取中文摘要

Protein phosphorylation and dephosphoryaltion are involved in the signal transduction pathways of stomatal guard cells. Since the guard cells can respond to both blue light and phytohormone abscisic acid, we investigated these responses using guard cell protoplasts.The blue light receptor is autophosphorylated in response to blue light, and a 14-3-3 protein was found to bind to phosphorylated serine in phototropin. The site is identified to be localized between LOV1 and LOV2.We found that ABA inhibits this blue light signaling pathways in stomatal guard cells. ABA inhibited the phosphorylation of the plasma membrane H^+-ATPase and inhibited the H^+ pumping from guard cells. We also found that ABA inhibited the ATP hydrolytic activity of the plasma membrane H^+-ATPase.