Molecular cloning of a pea H1 histone cDNA

A pea (Pisum sativum, var. Little Marvel) H1 histone cDNA has been isolated from a λgt11 expression vector library. This cDNA has been sequenced and shown to represent the entire protein‐coding region of the mRNA. The deduced protein sequence is 265 amino acids long (28018 Da) and contains 70 lysines and 3 arginines. The structure of the encoded protein is comparable to animal lysine‐rich histones. The central region, which has an amino acid composition similar to that found in the globular domains of animal lysine‐rich histones, is flanked by an amino‐terminal region rich in lysine, glutamic acid and proline and by a carboxyl‐terminal region rich in lysine, alanine, valine and proline. Despite the structural similarities, the protein has little sequence homology with animal lysine‐rich histones. This H1 protein is unusual because 12 of the first 40 amino acids are glutamic acid.