CLONING OF A NOVEL HUMAN TESTIS MESSENGER-RNA SPECIFICALLY EXPRESSED IN TESTICULAR HAPLOID GERM-CELLS, HAVING UNIQUE PALINDROMIC SEQUENCES AND ENCODING A LEUCINE-ZIPPER DIMERIZATION MOTIF

A novel gene coding for a human sperm surface protein (HSS) has been c loned from a human testis cDNA library, The 2.5 kb cDNA (hss) contains five direct repeats, three mirror repeats, three possible stem loop s tructures and three unique palindromic motifs located at functionally relevant positions, Open reading frame encodes a protein of 766 amino acids, The deduced protein analysis revealed a NH2 terminus extracellu lar domain having a leucine zipper (LZ) motif, a transmembrane helical domain and a cytoplasmic domain at the COOH terminus, Tissue specific expression studies demonstrated the presence of hss transcript only i n testis, Cell type expression of hss mRNA was observed only on the ro und spermatids suggesting haploid germ cell expression. (C) 1998 Acade mic Press.