Absent, Small Or Homeotic Like Protein (ASH1L)

ASH1L encodes a member of the trithorax group of transcriptional activators. The protein contains four AT hooks, a SET domain, a PHD-finger motif, and a bromodomain. It is localized to many small speckles in the nucleus, and also to cell-cell tight junctions.The deduced 2,962-amino acid protein contains a SET domain, a PHD finger, and 4 AT hooks. It also has a bromodomain-like region that is not present in Drosophila Ash1. Northern blot analysis detected a 10.5-kb transcript expressed in all tissues examined, with highest levels in brain, kidney, and heart. Immunostaining of epithelial and breast cancer cell lines and primary foreskin fibroblasts detected expression of ASH1 in 2 distinct cellular compartments: in small speckles uniformly distributed throughout the nucleoplasm, and at cell-cell junctions.