Occurrence of two somatostatin variants in the frog brain: Characterization of the cDNAs, distribution of the mRNAs, and receptor-binding affinities of the peptides

摘要

In tetrapods, only one gene encoding a so- matostatin precursor has been identified so far. The present study reports the characterization of the cDNA clones that encode two distinct somatostatin precursors in the brain of the frog Rana ridibunda. The cDNAs were isolated by using degenerate oligonucleotides based on the sequence of the central region of somatostatin to screen a frog brain cDNA library. One of the cDNAs encodes a 115-amino acid protein (prepro-somatostatin-14; PSS1) that exhibits a high degree of structural similarity with the mammalian somatostatin precursor.