Three cDNAs (named pVC1, pVC2 and pVC3) have been isolated from a giant alga,
Acetabularia acetabulum that encoded the N, N´- icyclohexylcarbodimide-binding
16 kDa proteolipid subunit of V-ATPase. The open reading frames of pVC1, pVC2
and pVC3 predicted the polypeptides of 164, 167 and 168 amino acids with the
molecular masses of 16.5, 16.7 and 16.8 kDa, respectively. Seventy nine percent
identity between pVC1 and pVC2 or pVC3 and 95% identity between pVC2 and pVC3
was observed. PVC1 and pVC2/pVC3 showed extensive divergences in their 3´
-untranslated region, while pVC2 and pVC3 possessed the same 3´ -untranslated
region. The deduced amino acid sequences of the three cDNA clones showed extensive
similarities with that of proteolipids of oat (75 to 80%), bovine (55%) and
yeast (55%) V-ATPase. Based on hydropathy plot, four membrane-spanning domains
were predicted, in which domain IV was especially conserved among different
species. This domain showed 96-100% identity in amino acid sequences between
the A. acetabulum and the oat proteolipid in which a glutamate residue
is included, the putative N, N´-dicyclohexylcarbodimide-binding residue.
M. Habibur Rahman and Mikiko Ikeda , 2002. Molecular Cloning of cDNAs Encoding the Proteolipid Subunit of the Vacuolar H+-ATPase of Acetabularia acetabulum. Pakistan Journal of Biological Sciences, 5: 338-342.