ASH2L Antibody (NB600-281) (0.1 mg)

The ash2 gene is a member of the trithorax group of genes whose products function to maintain active transcription of homeotic selector genes. Mutations in ash2 cause the homeotic transformations expected for a gene in this group but, in addition, cause a variety of pattern formation defects that are not necessarily expected. The ash2 gene is located in cytogenetic region 96A17-19 flanked by slowpoke and tolloid and is included in a cosmid that contains part of slowpoke. Ash2, the product of the Drosophila trxG gene absent, small, or homeotic discs 2 (ash2) is a component of a 500-kD complex. ASH2 binds directly to Skittles (Sktl), a predicted phosphatidylinositol 4-phosphate 5-kinase, and the association of these proteins is functionally significant. Histone H1 hyperphosphorylation is dramatically increased in both ash2 and sktl mutant polytene chromosomes. These results suggest that Ash2 maintains active transcription by binding a producer of nuclear phosphoinositides and downregulating histone H1 hyperphosphorylation. Both Ash2 and Sktl accumulate on polytene chromosomes and in the nucleolus. These results suggest that their physical association and functions involve chromatin and, perhaps, ribosomal DNA transcription. Ash2 accumulates normally on sktl mutant chromosomes while Sktl does not accumulate on ash2 mutant chromosomes.