Characterization of rat calcitonin mRNA.

Autor: Amara SG, David DN, Rosenfeld MG, Roos BA, Evans RM
Jazyk: angličtina
Zdroj: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 1980 Aug; Vol. 77 (8), pp. 4444-8.
DOI: 10.1073/pnas.77.8.4444
Abstrakt: A chimeric plasmic containing cDNA complementary to rat calcitonin mRNA has been constructed. Partial sequence analysis shows that the insert contains a nucleotide sequence encoding the complete amino acid sequence of calcitonin. Two basic amino acids precede and three basic amino acids follow the hormone sequence, suggesting that calcitonin is generated by the proteolytic cleavage of a larger precursor in a manner analogous to that of other small polypeptide hormones. The COOH-terminal proline, known to be amidated in the secreted hormone, is followed by a glycine in the precursor. The cloned calcitonin DNA was used to characterize the expression of calcitonin mRNA. Cytoplasmic mRNAs from calcitonin-producing rat medullary thyroid carcinoma lines and from normal rat thyroid glands contain a single species, 1050 nucleotides long, whch hybridizes to the cloned calcitonin cDNA. The concentration of calcitonin mRNA sequences is greater in those tumors that produce larger amounts of immunoreactive calcitonin. RNAs from other endocrine tissues, including anterior and neurointermediate lobes of rat pituitary, contain no detectable calcitonin mRNA.
Databáze: MEDLINE