CLONING AND MAPPING OF BOVINE ZFX GENE TO THE LONG ARM OF THE X-CHROMOSOME (XQ34) AND HOMOLOGOUS MAPPING OF ZFY GENE TO THE DISTAL REGION OF THE SHORT ARM OF THE BOVINE (YP13), OVINE (YP12-P13), AND CAPRINE (YP12-P13) Y-CHROMOSOME

A part of mouse Zfy-2 sequence was synthesized and used to screen a ge nomic library of the spinous country-rat (Tokudaia osimensis spp., 2n = 45). An isolated clone had the C-terminal region of Zfy, which consi sted of 1190 bp, encoded 336 amino acid residues, and harbored 11 out of 13 zinc finger motifs. With this as a probe, a bovine testis cDNA l ibrary was screened. Two ZFX clones were isolated and their sequences combined. The short sequence, lacking part of the 5' upstream region, was amplified by PCR or RT-PCR, cloned, and sequenced, A full-length Z FX was constructed by combining these three sequences, The bovine ZFX consisted of 5328 bp and encoded 800 amino acid residues, which contai ned 13 zinc finger motifs. ZFX was used as a probe for fluorescence in situ hybridization and was mapped to Xq34, different from its previou sly reported site at Xq21-q231. A SINE (short interspersed nuclear ele ment) sequence consisting of 188 bp was found close to the end of the 3'-untranslated region of ZFX. The SINE sequence hybridized to all bov ine chromosomes. ZFY is highly homologous with ZFX and, as a result, Z FY could be mapped simultaneously. ZFY was mapped to the distal region of the short arm of the Y Chromosome (Chr) (Yp13), contradicting the previously reported position Yq1. Ovine and caprine ZFY were also mapp ed with bovine ZFX. Both were mapped to the distal region of the short arm of the Y Chr (Yp 12-p13). Ovine ZFX was mapped to a region close to the centromere of the X Chr (Xq13).