SMARCA4 : SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4
Description
The SMARCA4 (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 4) is a protein-coding gene located on chromosome 19.
The SMARCA4 gene provides instructions for making a protein called BRG1, which forms one piece (subunit) of several different protein groupings called SWI/SNF protein complexes. SWI/SNF complexes regulate gene activity (expression) by a process known as chromatin remodeling. Chromatin is the network of DNA and protein that packages DNA into chromosomes. The structure of chromatin can be changed (remodeled) to alter how tightly DNA is packaged. Chromatin remodeling is one way gene expression is regulated during development; when DNA is tightly packed, gene expression is lower than when DNA is loosely packed. The BRG1 protein uses a molecule called ATP to provide energy for chromatin remodeling, although the protein's specific role in remodeling is unclear.Through their ability to regulate gene activity, SWI/SNF complexes are involved in many processes, including repairing damaged DNA; copying (replicating) DNA; and controlling the growth, division, and maturation (differentiation) of cells. Through these processes, the BRG1 protein and other SWI/SNF subunits are thought to act as tumor suppressors, which keep cells from growing and dividing too rapidly or in an uncontrolled way.
SMARCA4 plays a crucial role in regulating gene expression by modifying chromatin structure. It acts as a component of various SWI/SNF chromatin remodeling complexes, which utilize ATP to alter DNA-histone interactions within nucleosomes. SMARCA4 participates in both gene activation and repression, depending on the specific context. One notable function is its involvement in the CREST-BRG1 complex, which regulates promoter activation by releasing repressor complexes and recruiting activator complexes in a calcium-dependent manner. Notably, SMARCA4 is essential for neuronal development, contributing to both neural progenitor proliferation and postmitotic neuronal differentiation. It also plays a role in regulating genes involved in dendrite growth. Moreover, SMARCA4 interacts with various other proteins, including ZEB1, DLX1, and Evf2, to regulate a wide range of cellular processes, such as epithelial-mesenchymal transition (EMT) and thermogenic gene expression.
SMARCA4 is also known as BAF190, BAF190A, BRG1, CSS4, MRD16, OTSC12, RTPS2, SNF2, SNF2-beta, SNF2L4, SNF2LB, SWI2, hSNF2b.
Associated Diseases
- Coffin-Siris syndrome 4
- Rhabdoid tumor predisposition syndrome 2
- Coffin-Siris syndrome
- Lung cancer
- Rhabdoid tumor predisposition syndrome
