BRG1 (Brahma-Related Gene 1), encoded by SMARCA4, is the ATPase subunit of the SWI/SNF (SWItch/Sucrose Non-Fermentable) chromatin remodeling complex. This complex uses the energy of ATP hydrolysis to slide, evict, or restructure nucleosomes, dynamically regulating DNA accessibility for transcription, DNA repair, and replication. BRG1 is essential for development, neuronal differentiation, and synaptic plasticity, and its dysfunction has been implicated in Alzheimer's disease, Parkinson's disease, and cancer. [@hu2020]
Overview
BRG1 protein is the central catalytic engine of the SWI/SNF complex, one of the most important epigenetic regulators in eukaryotes. The SWI/SNF complex remodels chromatin by altering nucleosome positions, thereby controlling access to DNA for transcription factors, DNA repair machinery, and the transcriptional machinery. BRG1-containing complexes regulate thousands of genes, with particular importance in neuronal development and function. [@dalessio2018]
<div class="infobox infobox-protein">
| Property | Value | |----------|-------| | Protein Name | BRG1 (SMARCA4) | | Gene | SMARCA4 | | UniProt ID | P51532 | | PDB ID | 6EFA, 6GRG | | Molecular Weight | 185 kDa | | Subcellular Localization | Nucleus (chromatin-associated) | | Protein Family | SNF2 superfamily, SWI/SNF family | | Aliases | BRG1, SNF2L4, BAF190, SMARCA4 |
</div>
Structure
BRG1 contains characteristic domains:
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title: BRG1 Protein
BRG1 Protein (SMARCA4)
Introduction
BRG1 (Brahma-Related Gene 1), encoded by SMARCA4, is the ATPase subunit of the SWI/SNF (SWItch/Sucrose Non-Fermentable) chromatin remodeling complex. This complex uses the energy of ATP hydrolysis to slide, evict, or restructure nucleosomes, dynamically regulating DNA accessibility for transcription, DNA repair, and replication. BRG1 is essential for development, neuronal differentiation, and synaptic plasticity, and its dysfunction has been implicated in Alzheimer's disease, Parkinson's disease, and cancer. [@hu2020]
Overview
BRG1 protein is the central catalytic engine of the SWI/SNF complex, one of the most important epigenetic regulators in eukaryotes. The SWI/SNF complex remodels chromatin by altering nucleosome positions, thereby controlling access to DNA for transcription factors, DNA repair machinery, and the transcriptional machinery. BRG1-containing complexes regulate thousands of genes, with particular importance in neuronal development and function. [@dalessio2018]
<div class="infobox infobox-protein">
| Property | Value | |----------|-------| | Protein Name | BRG1 (SMARCA4) | | Gene | SMARCA4 | | UniProt ID | P51532 | | PDB ID | 6EFA, 6GRG | | Molecular Weight | 185 kDa | | Subcellular Localization | Nucleus (chromatin-associated) | | Protein Family | SNF2 superfamily, SWI/SNF family | | Aliases | BRG1, SNF2L4, BAF190, SMARCA4 |
</div>
Structure
BRG1 contains characteristic domains:
N-terminal domain - Protein interaction motifs, including Bromo domain
ATPase domain - SNF2-type helicase domain with two RecA-like lobes
The ATPase domain adopts a bipartite structure typical of chromatin remodelers, with a hinge region allowing conformational changes during the remodeling cycle.
Normal Function
BRG1 in the nervous system:
Chromatin remodeling - Opens chromatin for transcription