H2A.F: an extremely variant histone H2A sequence expressed in the chicken embryo.

Abstract
A c[complementary] DNA clone bank was constructed from chicken embryonic RNA. Clones hybridizing poorly to embryonic histone gene probes were selected as possible variant gene transcripts. The DNA sequence of 1 cDNA predicts an extremely variant H2A protein (H2A.F), which is 40% divergent from the most abundant H2A protein in chicken erythrocyte chromatin. The H2A.F gene is not highly conserved across large species barriers, but in the chicken there may be a family of linked genes. The H2A.F mRNA is .apprxeq. 820 base pairs in length and, unlike most other histone mRNAs, is polyA. Significantly, the H2A.F transcript shows a limited tissue distribution in the chicken embryo.