IDENTIFICATION OF AN ARABIDOPSIS-THALIANA GENE ENCODING A PLASMA-MEMBRANE H-ATPASE WHOSE EXPRESSION IS RESTRICTED TO ANTHER TISSUES()

A gene (aha9) for a plasma membrane H+-ATPase was isolated from an Ara bidopsis thaliana genomic library and sequenced. Comparison of the aha 9 predicted amino acid sequence with those of aha1, 2 and 3 and analog ous genes from other species indicated the existence of at least two a ha gene subfamilies whose divergence precedes that of the Nicotiana an d Arabidopsis species. Transcript analysis in various organs revealed expression of aha9 in flower tissues only. Introduction of aha9 into N icotiana tabacum by genetic transformation gave rise to transgenic pla nts which also express aha9 in flower tissues. A more detailed analysi s showed that aha9 expression was restricted to anther tissues.