Abstract
Somatostatin, a tetradecapeptide hormone, is produced in numerous organs including the hypothalamus, pancreatic islets, and the gastrointestinal tract. Recently we identified two separate biosynthetic precursors of somatostatin (M(r)=16,000 and 14,000) among the cell-free translation products encoded by mRNAs prepared from the islets of the anglerfish. The nucleotide sequence of a cloned cDNA encoding the larger of the two pre-prosomatostatins revealed the sequence of the tetradecapeptide somatostatin at the COOH terminus of a polypeptide of 119 amino acids. We now have prepared poly(A)RNA from the intestine of the anglerfish and by immunoprecipitation analyses find a single somatostatin-related translation product that co-migrates during electrophoresis on sodium dodecyl sulfate-polyacrylamide gels with the larger islet pre-prosomatostatin (M(r)=16,000). Analyses of the sizes of the intestinal and islet mRNAs by agarose gel electrophoresis and hybridization with 32P-labeled cDNA containing the coding sequence for the large islet pre-prosomatostatin showed that the complementary RNA in the intestine (600 bases) is 30 nucleotides smaller than that in the islet (620-630 bases). These observations indicate that a gene encoding somatostatin is expressed in the intestine and suggest that the intestinal mRNA is distinct from the two mRNAs encoding the islet somatostatins.
Original language | English (US) |
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Pages (from-to) | 1499-1501 |
Number of pages | 3 |
Journal | Journal of Biological Chemistry |
Volume | 256 |
Issue number | 4 |
State | Published - 1981 |
Externally published | Yes |
ASJC Scopus subject areas
- Biochemistry
- Molecular Biology
- Cell Biology