CHROMOSOMAL ASSIGNMENT OF 3 NOVEL MOUSE GENES EXPRESSED IN TESTICULARCELLS

The chromosomal positions of three genes that are selectively expresse d in mouse testis cells have been identified. These genes include (i) TAZ83, which codes for an early- to mid-pachytene germ cell stage-expr essed, cysteine-rich transmembrane protein (cyritestin) with homologie s to various snake toxins and guinea pig sperm-egg fusion proteins; (i i) TNZ1, which is expressed in neonatal Leydig cells; and (iii) TAZ4, a testis-specific gene isolated by immunoscreening with antiserum rais ed against Sertoli cell membranes. Our experimental data, derived from chromosomal in situ hybridizations and RFLP studies of genetic backcr osses, indicate that (i) the TAZ83 (cyritestin) gene maps to chromosom e 8, band A2, near the Plat locus; (ii) TNZ1 is located in the proxima l region of chromosome II; and (iii) TAZ4 is located at band D in the distal portion of chromosome 11, near the Hlr1 locus, with a related s equence, TAZ4-rs1, in the proximal part of chromosome 1. (C) Academic Press, Inc.