Construction of chimeric plasmids containing histone H5 cDNA from hen erythrocyte. DNA sequence of a fragment derived from the 5' region of H5 mRNA.

We report that construction and characterization of chicken erythrocyte histone H5 cDNA recombinant plasmids. cDNA was synthesized from poly(A)+ polysomal RNA enriched in H5 mRNA and inserted into the PstI site of pBR322. Several clones containing H5 cDNA sequences were obtained and one of them (p541), expressing H5 antigenic determinants, was sequenced. The DNA insert of p541 contains 118 nucleotides from the 5' non-translated region of H5 mRNA and sequences coding for up to residue 46 of the N-terminus of the arginine (position 15) H5 variant. There is a strikingly high number of repeated sequences both in the leader and coding region; among these, the octanucleotide 5' GCG GCG GC 3' is found five times along the sequence. Although the H5 mRNA 5' leader is GC-rich (66%), there is an AT-rich region, about 16 nucleotides long, which shares strong homology with the leaders of sea urchin histone H1 mRNAs.