ISOLATION OF RAT GNRH RECEPTOR CDNA HAVING DIFFERENT 5'-NONCODING SEQUENCE

A rat GnRH receptor cDNA was cloned with 1317 base pairs (bp) from a p ituitary cDNA library. This clone had a full amino acid coding region, with 172 and 161 bp noncoding sequences in 5'- and 3'-flanking region s of the coding region, respectively. The nucleotide sequence of amino acid coding region was completely identical to that of previous repor t by Kaiser et al. (1992), but 5'-noncoding region was much longer tha n the previously reported one and its sequence was different. This 5'- noncoding region could be divided into two subregions on the basis of similarity between the two sequences. The 32 bp sequence flanking the coding region was completely identical to the previous report, but rem aining 5'-end sequence almost totally lacked similarity. In the 3'-fla nking region of coding region, 167 bp-long sequence was also newly ide ntified. The new species of GnRH receptor mRNA found in the present st udy suggests that the presence of various mechanisms of GnRH receptor expression in the lat pituitary.