Anti-Silencing Function 1 Homolog B (ASF1B)

ASF1B encodes a member of the H3/H4 family of histone chaperone proteins and is similar to the anti-silencing function-1 gene in yeast. The encoded protein is the substrate of the tousled-like kinase family of cell cycle-regulated kinases, and may play a key role in modulating the nucleosome structure of chromatin by ensuring a constant supply of histones at sites of nucleosome assembly.

The deduced 203-amino acid ASF1B protein has a calculated molecular mass of 22.4 kD. ASF1B and ASF1A share 71% amino acid identity, and they share about 50% identity with yeast Asf1, which has a C-terminal acidic stretch not found in the human ASF1 proteins.