High impact information on ash2

• We propose that eukaryotic Set1Cs are H3 lysine 4 methyltransferases and are related to trxG action through association with Ash2 homologues [1].
• Transcriptional network controlled by the trithorax-group gene ash2 in Drosophila melanogaster [2].
• The transcription factor absent, small, or homeotic discs 2 (ash2) gene is a member of the trithorax group of positive regulators of homeotic genes [2].
• The seven-member 363-kDa complex contains homologs of Drosophila melanogaster proteins Ash2 and Trithorax and Caenorhabditis elegans protein DPY-30, which are implicated in the maintenance of Hox gene expression and regulation of X chromosome dosage compensation, respectively [3].
• Moreover, loss-of-function phenotypes of the Egfr pathway are suppressed by ash2 mutants, while gain-of-function phenotypes are enhanced [4].

Biological context of ash2

• We also show that histone H1 hyperphosphorylation is dramatically increased in both ash2 and sktl mutant polytene chromosomes [5].
• Molecular genetic analysis of Drosophila ash2, a member of the trithorax group required for imaginal disc pattern formation [6].
• Abstract Drosophila ash2 is a member of the trxG gene super family, some human homologues of which are involved in hematopoiesis and leukemia [7].
• The penetrance of the homeotic phenotype in progeny from mutant mothers is increased by heterozygosis for alleles of ash-1 or ash-2 as well as for trithorax alleles [8].
• S. pombe Set1C mediates H3 Lys(4) methylation in vitro and contains the same eight subunits found in S. cerevisiae, including the homologue of the Drosophila trithorax Group protein, Ash2 [9].

Anatomical context of ash2

• Polyclonal antibodies directed against ASH2 detect the protein in imaginal discs and in the nuclei of salivary gland and fat body cells [6].

Associations of ash2 with chemical compounds

• In this article, we provide biochemical evidence that ASH2 binds directly to Skittles (SKTL), a predicted phosphatidylinositol 4-phosphate 5-kinase, and genetic evidence that the association of these proteins is functionally significant [5].

Regulatory relationships of ash2

• These results suggest that ASH2 maintains active transcription by binding a producer of nuclear phosphoinositides and downregulating histone H1 hyperphosphorylation [5].

Other interactions of ash2

• In this paper we examine the consequences of ash1 and ash2 mutations on the expression of homeotic selector genes in imaginal discs [10].
• Together, these experiments indicate that ash2 plays a role in two processes during wing development: (1) maintaining intervein cell fate, either by activation of intervein genes or inhibition of vein differentiation genes; and (2) keeping kni in an off state in tissues beyond the L2 vein [4].

Analytical, diagnostic and therapeutic context of ash2

• In an attempt to identify gene targets of ash2, we have performed an expression analysis by using cDNA microarrays [2].

References