SNF5 is a component of the yeast SWI/SNF complex, which is an ATP-dependent nucleosome-remodelling complex that regulates the transcription of a subset of yeast genes. SNF5 is a key component of all SWI/SNF-class complexes characterized so far. This family consists of the conserved region of SNF5, including a direct repeat motif. SNF5 is essential for the assembly promoter targeting and chromatin remodelling activity of the SWI-SNF complex. SNF5 is also known as SMARCB1, for SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily b, member 1, and also INI1 for integrase interactor 1. Loss-of function mutations in SNF5 are thought to contribute to oncogenesis in malignant rhabdoid tumors (MRTs).