THE NEW GENE DMX FROM DROSOPHILA-MELANOGASTER ENCODES A NOVEL WD-REPEAT PROTEIN

DmX is a novel gene from Drosophila melanogaster located on the X chro mosome in region 5D5/6-E1. The molecular analysis of the genomic and c DNA sequences of DmX shows that the gene spans appr. 16 kb and display s a mosaic structure with 15 exons. The 12 kb long DmX transcript is p resent in Drosophila embryos, larvae and adults of both sexes. The ope n reading frame of DmX encodes a novel WD-repeat protein, containing a t least 30 WD-repeat units. WD-repeat proteins contain a conserved mot if of approximately 40 amino acids (aa), usually ending with the dipep tide Trp-Asp (WD). Homologues of the DmX gene exist in other dipteran species, in Caenorhabditis elegans and human, revealing that DmX is an evolutionarily well conserved gene. The inferred DMX amino acid seque nce shows also limited, but significant similarity to a yeast ORF with unknown function. (C) 1998 Elsevier Science B.V. All rights reserved.