DNA sequences coding for the H2B histone of Psammechinus miliaris

Starting from restriction enzyme cleavage sites of known topologies the DNA sequences coding for two thirds of the H2B histone protein, together with some 3 inch extracistronic sequences, have been determined for the sea urchin Psammechinus miliaris. This unambiguously identifies this gene and further reveals its 5 inch-3inch polarity and accurate map position in a cloned histone DNA repeat unit.