SMARCA4

SMARCA4
Identifiers
Symbol	?
NCBI gene	6597
HGNC	11100
OMIM	603254
RefSeq	NM_003072
UniProt	P51532
Search for Structures Swiss-model Domains InterPro

SMARCA4 (SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin, Subfamily A, Member 4) is a gene that encodes a protein involved in chromatin remodeling. This protein is a part of the SWI/SNF complex, which is crucial for the regulation of gene expression by altering chromatin structure.

Function

SMARCA4 is a catalytic subunit of the SWI/SNF complex, which uses the energy derived from ATP hydrolysis to remodel chromatin. This process is essential for the regulation of transcription, DNA repair, replication, and recombination. The SMARCA4 protein, also known as BRG1, is involved in the activation and repression of various genes by modifying the accessibility of the DNA to transcription factors and other DNA-binding proteins.

Structure

The SMARCA4 protein contains several domains that are critical for its function:

• ATPase domain: This domain is responsible for the ATPase activity that provides the energy for chromatin remodeling.
• Bromodomain: This domain allows the protein to bind acetylated lysines on histone tails, facilitating its role in chromatin remodeling.
• Helicase domain: This domain is involved in the unwinding of DNA, which is necessary for the remodeling process.

Clinical Significance

Mutations in the SMARCA4 gene have been associated with several types of cancer, including:

• Rhabdoid tumors: These are aggressive tumors that can occur in the brain, kidney, and other tissues. Loss of SMARCA4 function is a common feature in these tumors.
• Lung cancer: SMARCA4 mutations have been identified in non-small cell lung cancer (NSCLC), particularly in the adenocarcinoma subtype.
• Ovarian cancer: SMARCA4 mutations are also implicated in small cell carcinoma of the ovary, hypercalcemic type (SCCOHT).

Research and Therapeutic Implications

Research into SMARCA4 and its role in chromatin remodeling is ongoing, with implications for cancer therapy. Targeting the SWI/SNF complex or compensatory pathways may offer new therapeutic strategies for cancers with SMARCA4 mutations.

Also see

• Chromatin remodeling
• SWI/SNF complex
• Gene expression regulation
• Cancer genetics