Rv. Patil et al., CLONING OF A NOVEL CDNA HOMOLOGOUS TO CHIP28 WATER CHANNEL FROM OCULAR CILIARY EPITHELIUM, Biochemical and biophysical research communications, 204(2), 1994, pp. 861-866
Water channel protein (CHIP28) has been initially identified from huma
n erythrocyte and subsequently localized in human kidney, rat kidney a
nd bovine corneal endothelium. We report here cloning of homologous cD
NA (CHIP29) from an expression cDNA library constructed from bovine ci
liary epithelium poly A(+) that codes a 271 amino acid, 28.8 kDa prote
in. At the amino acid level, bovine CHIP29 is 91% identical to the CHI
P28 protein. Analysis of the deduced amino acid sequence indicated a h
ydrophobic protein with six membrane spanning domains, one N-linked gl
ycosylation site, two consented NPA boxes common to MIP26 family prote
ins, and conserved amino acid residue cysteine 189 common to water cha
nnels. Northern blotting revealed a major mRNA of 2.8 Kb size expresse
d in bovine ciliary epithelium. The results presented here confirm the
presence of water channel gene in the bovine ciliary epithelium, a pr
imary site for the aqueous humor production. (C) 1994 Academic Press,
Inc.