This is a tetradecapeptide exerting a growth hormone (GH) release-inhibiting activity. SS also has a large variety of neuromodulatory and gastrointestinal actions, mostly as an inhibitory hormone. SS of 14 aa residues (SS-14) was first isolated from ovine hypothalamic extracts by Roger Guillemin’s group in 1973 and was originally named GH inhibiting factor. An N-terminally extended form of 28 aa residues (SS-28) was isolated later from the porcine gut. SS cDNA that encodes a precursor for SS-14 and SS-28, a product of the SS1 gene (approved symbol SST), was first cloned from the anglerfish pancreas in 1980. In this report, another SS cDNA encoding a different precursor (formerly called SSII), a product of the SS3 gene, was also isolated. Subsequently, cDNAs and genes encoding SS precursors have been identified in many animals by molecular cloning and bioinformatic analyses, and so far six paralogous genes (SS1, SS2, SS3, SS4, SS5, and SS6) have been identified in vertebrates. Accordingly, two SS-related peptides, cortistatin (CST)5 and neuronostatin, have been identified.

This is a tetradecapeptide exerting a growth hormone (GH) release-inhibiting activity. SS also has a large variety of neuromodulatory and gastrointestinal actions, mostly as an inhibitory hormone. SS of 14 aa residues (SS-14) was first isolated from ovine hypothalamic extracts by Roger Guillemin’s group in 1973 and was originally named GH inhibiting factor. An N-terminally extended form of 28 aa residues (SS-28) was isolated later from the porcine gut. SS cDNA that encodes a precursor for SS-14 and SS-28, a product of the SS1 gene (approved symbol SST), was first cloned from the anglerfish pancreas in 1980. In this report, another SS cDNA encoding a different precursor (formerly called SSII), a product of the SS3 gene, was also isolated. Subsequently, cDNAs and genes encoding SS precursors have been identified in many animals by molecular cloning and bioinformatic analyses, and so far six paralogous genes (SS1, SS2, SS3, SS4, SS5, and SS6) have been identified in vertebrates. Accordingly, two SS-related peptides, cortistatin (CST)5 and neuronostatin, have been identified.