CDNA CLONING OF EEL (ANGUILLA-ANGUILLA) SOMATOLACTIN

The nucleotide sequence of the cDNA coding for eel somatolactin (SL), a pituitary hormone belonging to the growth hormone (GH)/prolactin (PR L) family, has been determined. The full-length eel SL cDNA (1213 bp) encodes a protein of 229 amino acids (aa), with a putative signal pept ide of 24 aa and a mature protein of 204 aa. Eel SL contains seven Cys residues found to be characteristic of SLs, and two potential N-glyco sylation sites. Significant sequence homology between eel and seven ot her fish SLs (42% aa identity, 63% aa similarity) reveal SL to be high ly conserved. A higher sequence identity of SL to GH than PRL is sugge sted by the comparison of these hormones in eel and chum salmon.