Histone acetyl transferases (HATs) play a crucial role in eukaryotes by regulating chromatin architecture and locus specific transcription. GCN5 (KAT2A) is a member of the GNAT (Gcn5-related N-acetyltransferase) family of HATs. In metazoans this enzyme is found in two functionally distinct coactivator complexes, SAGA (Spt Ada Gcn5 acetyltransferase) and ATAC (Ada Two A-containing).
View Article and Find Full Text PDFThe SGF29 protein binds to tri-methylated lysine-4 of histone H3 (H3K4me3), which is a histone modification associated with active promoters. Human SGF29 is a subunit of the histone acetyltransferase module of the SAGA (Spt-Ada-Gcn5 acetyltransferase) and ATAC (Ada-Two-A-containing 2A) co-activator complexes. Previous work revealed that the SAGA complex is recruited to endoplasmic reticulum (ER) stress target genes and required for their induction.
View Article and Find Full Text PDFAll DNA-related processes rely on the degree of chromatin compaction. The highest level of chromatin condensation accompanies transition to mitosis, central for cell cycle progression. Covalent modifications of histones, mainly deacetylation, have been implicated in this transition, which also involves transcriptional repression.
View Article and Find Full Text PDFHistone acetyl transferases (HATs) play a crucial role in eukaryotes by regulating chromatin architecture and locus-specific transcription. The GCN5 HAT was identified as a subunit of the SAGA (Spt-Ada-Gcn5-Acetyltransferase) multiprotein complex. Vertebrate cells express a second HAT, PCAF, that is 73% identical to GCN5.
View Article and Find Full Text PDFOne of the central questions in eukaryotic transcription is how activators can transmit their signal to stimulate gene expression in the context of chromatin. The multisubunit SAGA coactivator complex has both histone acetyltransferase and deubiquitination activities and remodels chromatin to allow transcription. Whether and how SAGA is able to regulate transcription at specific loci is poorly understood.
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