High impact information on CHD1

• Site-directed mutations in the conserved residues of the chromo domain confirm that it is required for proper silencing and directional switching of the mating type, like SET domain [1].
• We suggest that a 'transcriptional stress' signal sensed through Set1, Chd1, and possibly other factors, causes H3K4 hypermethylation of newly deposited nucleosomes at downstream positions within a gene [2].
• Thirdly, we demonstrate that deletion of CHD1 suppresses a cold-sensitive spt5 mutation that is also suppressed by defects in the Paf1 complex and RNA pol II [3].
• First, we identified Chd1 in a two-hybrid screen for proteins that interact with Rtf1, a member of the Paf1 complex that associates with RNA pol II and regulates transcription elongation [3].
• Chromatin remodeling protein Chd1 interacts with transcription elongation factors and localizes to transcribed genes [3].

Biological context of CHD1

• Our findings indicate that yeast and human CHD1 have diverged in their ability to discriminate covalently modified histones and link histone modification-recognition and non-covalent chromatin remodeling activities within a single human protein [4].
• Thus, the ISWI and Chd1 remodelling factors are not only involved in transcription-related chromatin remodelling, but also are required to maintain a specific chromatin configuration across the yeast genome [5].
• Molecular biology of the chromo domain: an ancient chromatin module comes of age [6].
• Chd1 chromodomain links histone H3 methylation with SAGA- and SLIK-dependent acetylation [7].
• Splicing assays show that CHD1 overexpression can affect alternative splicing [8].

Associations of CHD1 with chemical compounds

• Human but not yeast CHD1 binds directly and selectively to histone H3 methylated at lysine 4 via its tandem chromodomains [4].
• These observations implicate SET domain proteins as multifunctional chromatin regulators with activities in both eu- and heterochromatin--a role consistent with their modular structure, which combines the SET domain with additional sequence motifs of either a cysteine-rich region/zinc-finger type or the chromo domain [9].

Regulatory relationships of CHD1

• The ISWI and CHD1 chromatin remodelling activities influence ADH2 expression and chromatin organization [5].
• Similar to the suppression by chd1, mutations in the SET2 histone methyltransferase also suppress defects caused by yFACT mutations. chd1 and set2 are additive in suppressing pob3, suggesting that Chd1 and Set2 act in distinct pathways [10].

Other interactions of CHD1

• Surprisingly, a strong assembly defect is also associated with deletion of CHD1, suggesting that like other SNF2-related groups of nucleic acid-stimulated ATPases, the chromodomain (CHD) group may contain a member involved in chromatin reconstitution [11].
• Replication-independent assembly of nucleosome arrays in a novel yeast chromatin reconstitution system involves antisilencing factor Asf1p and chromodomain protein Chd1p [11].
• Instead, a destabilized chromatin structure on the ADH2 coding and termination region is observed in the absence of Isw1 or Chd1 in repressing conditions [5].
• Here we show that the absence of the Isw1 and Chd1 ATP-dependent chromatin remodelling activities delays the maximal expression of ADH2 without impairing the chromatin remodelling that occurs upon activation [5].
• Finally, we demonstrate that Chd1, Rtf1 and Spt5 associate with actively transcribed regions of chromatin [3].

Analytical, diagnostic and therapeutic context of CHD1

• Using genomic DNA arrays, we identified genes whose expression is affected by the absence of Chd1p [12].

References