Cloned cDNAs containing sequences coding for the β subunit of bovine thyrotropin have been identified. The complete nucleotide sequence of the largest of the β subunit cDNA inserts has been determined. This cDNA contains 35 nucleotides from the 5' untranslated region of thyrotropin β subunit mRNA and 60 nucleotides coding for an NH2-terminal precursor segment. This is followed by 339 nucleotides which code for the published amino acid sequence of the thyrotropin β subunit. Following the 339 nucleotide β subunit coding sequence, no termination codon is encountered for another 15 nucleotides. Thus, the cDNA codes for a thyrotropin β subunit containing an additional 5 amino acids at the COOH terminus. The cDNA also contains 82 nucleotides of 3' untranslated sequence followed by a short poly(A) segment. Comparison of the bovine cDNA sequence to the recently described mouse thyrotropin β subunit cDNA sequence reveals considerable homology throughout the coding sequence, including the COOH-terminal extension. These findings suggest the possibility that a thyrotropin β subunit precursor is processed at both the NH2 and COOH termini.
|Original language||English (US)|
|Number of pages||4|
|Journal||Journal of Biological Chemistry|
|Publication status||Published - 1984|
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