SMARCB1
SMARCB1 encodes a core SWI/SNF/BAF chromatin-remodeling subunit that supports chromatin access and transcriptional regulation[1]. Mechanistically, SMARCB1 enables BAF-mediated enhancer activation and helps activate bivalent promoters through opposition to Polycomb repression[2]. In malignant rhabdoid tumor models, biallelic SMARCB1 loss defines disease biology and rewires patient-specific distal enhancers linked to MYC expression[3][4]. Compared with related BAF assemblies, SMARCB1-containing complexes preferentially occupy enhancers, whereas BRD9-containing SMARCB1-lacking complexes localize at promoters and enhancers and create a BRD9 vulnerability after SMARCB1 loss[5]. SMARCB1 has two splice isoforms generated by alternative splicing within exon 2, producing 385- and 376-amino-acid proteins[6]. For experimental applications, SMARCB1-deficient models support studies of enhancer regulation, Polycomb antagonism, MYC-driven oncogenic transcription, and BRD9 dependency[2][3][5].- SMARCB1 links BAF chromatin remodeling to enhancer activation and Polycomb-opposed promoter regulation. - SMARCB1-deficient tumor models enable mechanistic studies of MYC enhancers and BRD9 vulnerability.
References:
- [1]. SMARCB1 gene information from NCBI.
- [2]. Nakayama RT, et al. SMARCB1 is required for widespread BAF complex-mediated activation of enhancers and bivalent promoters. Nat Genet. 2017 Nov;49(11):1613-1623. [Content Brief]
- [3]. Versteege I, et al. Truncating mutations of hSNF5/INI1 in aggressive paediatric cancer. Nature. 1998 Jul 9;394(6689):203-6. [Content Brief]
- [4]. Liu NQ, et al. SMARCB1 loss activates patient-specific distal oncogenic enhancers in malignant rhabdoid tumors. Nat Commun. 2023 Dec 1;14(1):7762. [Content Brief]
- [5]. Wang X, et al. BRD9 defines a SWI/SNF sub-complex and constitutes a specific vulnerability in malignant rhabdoid tumors. Nat Commun. 2019;10(1):1881. [Content Brief]
- [6]. Bruder CE, et al. The mouse ortholog of the human SMARCB1 gene encodes two splice forms. Biochem Biophys Res Commun. 1999 Apr 21;257(3):886-90. [Content Brief]
