In the vacuolar-type H+-ATPase (V-ATPase), highly hydrophobic subunits known as the proteolipids are components of the integral membrane V0 sector. Previously, we described the identification of three different proteolipid genes in @entity2199 (Oka, T., Yamamoto, R., and Futai, M. (1997) J. Biol. Chem. 272, 24387-24392): @entity48832 and @entity69606 encoded 16-kDa subunits, and @entity48833 , a 23-kDa isoform. We report here that a third 16-kDa gene, @entity69607 , has been identified on chromosome IV. This is the first example in which four proteolipid genes have been found in a single organism. @entity69606 and @entity69607 exhibited 85% @entity377 identity within the open reading frames which encoded the identical @entity535 sequence. Northern blot analysis indicated that all four genes were expressed in a similar pattern during the worm life cycle; however, studies with transgenic worms indicated that the @entity69607 gene was expressed differently from other proteolipid genes in a cell-specific manner. These results implied that the isoforms of the proteolipids may be related to functional differences of V-ATPases in various cell types. Another new gene, @entity48834 , contained seven exons and was found to be located immediately downstream of @entity69607 . The two genes constitute a single transcriptional unit. The @entity48834 protein had 384 @entity1522 and shared strong sequence similarities with the C subunit, a component of the peripheral V1 sector of the V-ATPase, from @entity375 , @entity291 , and @entity1 . Expression of the @entity48834 cDNA complemented a null mutation of @entity69608 , the @entity375 C subunit gene, thus demonstrating that @entity48834 was the functional C subunit of @entity2199 .

Multiple genes for vacuolar-type ATPase proteolipids in XXXX . A new gene, @entity69607 , has a distinct cell-specific distribution.

@entity1 :: ('9606', 'Species') :: ['human'] @entity1522 :: ('CHEBI:33709', 'Chemical') :: ['amino acids'] @entity2199 :: ('6239', 'Species') :: ['C. elegans', 'Caenorhabditis elegans'] @entity535 :: ('CHEBI:33704', 'Chemical') :: ['amino acid'] @entity377 :: ('CHEBI:36976', 'Chemical') :: ['nucleotide'] @entity48833 :: ('174272(Tax:6239)', 'Gene') :: ['vha-4'] @entity48834 :: ('177017(Tax:6239)', 'Gene') :: ['VHA-11', 'vha-11'] @entity48832 :: ('176383(Tax:6239)', 'Gene') :: ['vha-1'] @entity69606 :: ('187779(Tax:6239)', 'Gene') :: ['vha-2'] @entity375 :: ('4932', 'Species') :: ['yeast'] @entity291 :: ('9913', 'Species') :: ['bovine'] @entity69608 :: ('853782(Tax:4932)', 'Gene') :: ['VMA5'] @entity69607 :: ('177018(Tax:6239)', 'Gene') :: ['vha-3']
@entity2199 :: (6239,Species) :: ['Caenorhabditis elegans']
