J. Ryerse et al., CLONING AND MOLECULAR CHARACTERIZATION OF A VOLTAGE-DEPENDENT ANION-SELECTIVE CHANNEL (VDAC) FROM DROSOPHILA-MELANOGASTER, Biochimica et biophysica acta. Biomembranes, 1327(2), 1997, pp. 204-212
A full length voltage-dependent anion-selective channel (VDAC) cDNA wa
s cloned from Drosophila melanogaster by expression library screening
using an antibody against an insect VDAC protein. The cDNA clone (deno
ted DmVDAC) is 1082 base pairs (bp) in length and contains an open rea
ding frame (bp 62-907) encoding a 282 amino acid protein which has a p
redicted molecular mass of 30 550 Da, a predicted pI of 6.98 and no cy
steines. Hydrophobicity analysis suggests 15 or 16 membrane-spanning d
omains. The DmVDAC amino acid sequence has variable homology with VDAC
s from other species ranging from 62% identity with a human VDAC to 23
% identity with a Dictyostelium discoideum VDAC. DmVDAC has 92% identi
ty with the 38 conserved residues in a VDAC consensus sequence, DmVDAC
was expressed in VDAC-null yeast but failed to rescue viability. DmVD
AC has 88% identity at the amino acid level and 99% identity at the nu
cleic acid level with a recently reported D. melanogaster VDAC sequenc
e (A. Messina et al., FEBS Lett. 384 (1996) 9-13). Homology analyses w
ith the Messina and other VDAC sequences indicate that the amino acid
differences are due to minor errors in the Messina sequence. Southern
blots and chromosomal in situ hybridizations suggest a single VDAC gen
e occurs in the fly with a locus at 32B on the left arm of the second
chromosome. (C) 1997 Elsevier Science B.V.