Partial amino acid sequence of rat pre-prolactin

Abstract

Rat pituitary mRNA was used to direct the cell-free synthesis of pre-prolactin labeled with [4,5-3H]leucine and either [35S]methionine or [35S]cystine. Sequence analysis of the labeled protein indicates that pre-prolactin has 29 amino acid residues joined to the N-terminus of the prolactin sequence. Leucine residues were found at positions 13, 14, 15, 16, 21 and 22, methionine residues at positions 1, 17 and 18, and a cysteine residue at position 24 of the precursor sequence. This partial sequence shows considerable similarity with other precursors that have been sequenced.