CLONING OF THE SEMENOGELIN-II GENE OF THE RHESUS-MONKEY - DUPLICATIONS OF 360 BP EXTEND THE CODING REGION IN MAN, RHESUS-MONKEY AND BABOON

The semenogelin II gene from the rhesus monkey has been cloned and cha racterized. The transcription unit is split into three exons of 97, 20 86 and 124 bp, with two intervening introns of 241 bp and 862 bp. The first exon codes for a 23-amino-acid signal peptide and the two amino- terminal residues of the secreted protein. The second exon codes for t he rest of the mature protein, and the third exon contains non-coding nucleotides only. Secreted rhesus monkey semenogelin II consists of 68 3 amino acid residues, has a calculated M(r) of 77362, is devoid of Cy s and Met, and displays a highly repetitive structure composed of ten 60-amino-acid repeats. Hybridization with genomic DNA showed that the semenogelin II gene of man, rhesus monkey and baboon has evolved throu gh extension of the coding region with 360-bp segments. In contrast, t he length of the semenogelin I gene of these species appears to be con served. The two genes are also present in some New World monkeys, as w as revealed by hybridization with genomic DNA from the marmoset. Howev er, another New World monkey, the cotton-top tamarin, carries only one semenogelin gene, but also has a gene that is similar to the mouse se menoclotin gene.