Abstract
The plasma membrane H+-ATPase generates an electrochemical gradient across the plasma membrane that provides a driving force for uptake of numerous nutrients, amino acids, peptides, and sucrose, by coupling with organ-specific transporters and for cell turgor maintenance. Recent studies have demonstrated that phosphorylation of a penultimate Thr in the C-terminus and subsequent binding of a 14-3-3 protein to the phosphorylated H+-ATPase are common physiological mechanism for activation in plant cells. However, in liverworts, which are the oldest extant lineage of land plants, the H+-ATPase has not been characterized. In this study, we performed molecular characterization the H+-ATPase in M. polymorpha. EST database search revealed that there are at least 8 H+-ATPase genes. Interestingly, four isoforms possess typical C-terminal region including the penultimate Thr. In contrast, the rest of isoforms lack such a C-terminal region. We will report phylogenetic analysis and expression properties during life cycle of all H+-ATPase isoforms in M. polymorpha.
