期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1983
卷号：80
期号：8
页码：2122-2126
DOI：10.1073/pnas.80.8.2122
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Double-stranded cDNA was synthesized from sucrose gradient-purified poly(A)+ mRNA from a mouse thyrotropic tumor, inserted into the Pst I site of plasmid pBR322 by using poly(dC) . poly(dG) homopolymeric extensions, and cloned in Escherichia coli RRI. Plasmids containing cDNA sequences coding for the beta subunit of thyrotropin (TSH) were identified by cell-free translation of hybrid-selected mRNA and immunoprecipitation with specific antibody to TSH beta subunit. Determination of the nucleotide sequence of one cDNA, 595 base pairs in length, allowed us to deduce the entire amino acid sequence of the mouse TSH beta subunit. The pre-beta subunit contains a 20-amino acid amino-terminal signal sequence followed by a 118-amino acid mature TSH beta subunit. There is 85-90% homology in amino acid sequence between mouse TSH beta subunit and subunits from man, pig, and cow; however, the mouse subunit contains an additional 5 or 6 amino acids at its carboxyl terminus compared to the bovine or human and pig subunits, respectively. TSH beta-subunit mRNA from mouse thyrotropic tumor was estimated to be 750 nucleotides in length by hybridization with labeled TSH beta-subunit cDNA.
