SNF2L, also known as SMARCA1 (SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily a, member 1), SWI or ISWI, is a 1,054 amino acid protein that localizes to the nucleus and contains one helicase C-terminal domain, one helicase ATP-binding domain and two SANT domains. Expressed as multiple alternatively spliced isoforms, SNF2L exists as a component of the nucleosome-remodeling factor (NURF) complex where it helps to facilitate the ATP-dependent perturbation of chromatin structure and may also be involved in brain development and neurite outgrowth. The gene encoding SNF2L maps to human chromosome X, which contains nearly 153 million base pairs and houses over 1,000 genes.