THE V-ATPASE A-SUBUNIT GENE (VMA-1) GIARDIA-LAMBLIA

The sequence of the gene encoding the A subunit of the vacuolar type A TPase from Giardia lamblia is reported. Comparison of the encoded prot ein with the homologous subunits of eukaryotic and archaebacterial ATP ases reveals high levels of similarity throughout the sequence (e.g., overall 49.1 and 44.6% identity to the homologous subunit from carrot and Halobacterium, respectively). An exception are three regions which are unique to the Giardia subunit. The largest of these regions conta ins motifs characteristic for eukaryotic spliceosomal introns; however , comparison to the cDNA shows that this region is also present in the mRNA.