Characterization of a cDNA encoding a precursor of Carassius RFamide, structurally related to a mammalian prolactin-releasing peptide.

We have characterized the cDNA encoding Carassius RFamide (C-RFa), which is structurally related to mammalian prolactin-releasing peptides (PrRPs), from the brain of the crucian carp. The deduced C-RFa precursor has been shown to comprise 117 amino acids, encoding a single C-RFa sequence. A comparative study of amino acid sequences has revealed that several sequences conserved in preproPrRPs are also found in the C-RFa precursor. Furthermore, the abundant presence of the C-RFa mRNA in the telencephalon, optic tectum, medulla oblongata, and proximal half eye ball was demonstrated by Southern blot analysis of RT-PCR products.