| 15580528 |
Inada M, Ueda A, Shi W, Takabe T: A stress-inducible plasma membrane protein 3 (AcPMP3) in a monocotyledonous halophyte, Aneurolepidium chinense, regulates cellular Na (+) and K (+) accumulation under salt stress. Planta. 2005 Jan;220(3):395-402. Epub 2004 Oct 2.
Regulation of ion homeostasis is fundamental to physiological activities in plants. Here, we report on the functional characterization of AcPMP3 [Aneurolepidium chinense (a monocotyledonous halophyte) plasma membrane protein 3] under salt stress. Expression of AcPMP3-1 and AcPMP3-2 genes was highly induced by various abiotic stresses, such as salt, cold and drought. Furthermore, abscisic acid, H (2) O (2) and salicylic acid also triggered expression of AcPMP3 genes. In the Deltanha1 Deltapmr2 Deltapmp3 yeast mutant, which lacks the major Na (+) efflux systems (Na (+)/H (+) antiporter and Na (+)-ATPase), its salt-sensitive phenotype was restored by expressing the AcPMP3-1 gene, and the transformants accumulated lesser amounts of Na (+) and K (+) than mutant cells under 50 mM NaCl and 500 mM KCl conditions, respectively. These results suggested that AcPMP3-1 plays a role as a regulator of both Na (+) and K (+) accumulation in the cells. In situ hybridization showed that the AcPMP3-1 transcript was localized in cells of the root cap and root epidermis, which strongly suggested that AcPMP3-1 is essential for regulating Na (+)/K (+) transportation between plant roots and the outer environment under salt stress. |
1(0,0,0,1) |