The human SNW1 gene contains 14 exons.

As a result of alternative splicing, SNW1 has two transcript variants (https://www.ncbi.nlm.nih.gov/gene/22938, 2017). The transcript 1, the long isoform, has 2207 nt mRNA which encodes a 571 amino acid (aa)-long protein (protein ID: NP_001305773.1). The transcript 2, which has 2146 nucleotides, differs in the 3 UTR and displays multiple coding region differences compared to transcript 1. One of the coding region differences results in a frame shift, giving rise to the isoform 2, which has 536 amino-acids with a distinct carboxyl-terminus (protein ID: NP_036377.1).

There is one reported pseudogene located on chromosome 1 (https://www.ncbi.nlm.nih.gov/gene/22938, 2017).

SNW domain containing protein 1 is also known as nuclear protein SkiP, nuclear receptor coactivator NcoA-62 or Ski interacting protein (SKIP).

The genes encoding SNW proteins are present throughout eukaryotic phylla, including lower eukaryotes, plants, fungi and animals. There is only one gene per genome, which encodes for a 60-80 kDa protein that predominantly localizes to the nucleus (Folk at al., 2004). SNW1 is suggested to contain protein interaction domains as well as a carboxyl-terminally located dimerization domain (Folk at al., 2004).

SNW1 is expressed in the brain, endocrine tissues, bone marrow and immune system, muscle, lung, liver, gall bladder, pancreas, gastrointestinal tract, kidney, urinary bladder, male and female specific tissues, adipose and soft tissues and skin, in which the expression levels are high except kidney (http://www.proteinatlas.org/ENSG00000100603-SNW1/tissue, 2017).

SNW1 localizes in the nucleus (Dahl et al., 1998).

SNW1 acts as a co-regulator for transcriptions regulated by vitamin D and RARA / RARB / RARG (retinoic acid receptors) as well as steroid hormone receptors including NR3C1 (glucocorticoid receptor), ESR1 / ESR2 (estrogen receptors), and AR (androgen receptor) (Folk at al., 2004). SNW1 also plays critical roles in the function of v-Ski avian retroviral oncogene, bone morphogenetic protein (BMP) during vertebrate embryogenesis (Wu et al, 2011), telomere function (Lackner et al, 2011) and Notch signaling-mediated transcription (Vasquez-Del Carpio, 2013). SNW1 is reported to counteract transcriptional repression induced by RB1 (retinoblastoma protein) as well (Prathapam et al. 2002). In addition to being a transcriptional co-regulator, SNW1 is an integral component of spliceosome by interacting with the U5 small nuclear ribonucleoprotein (snRNP) subcomplex of the activated spliceosome as a part of the PRPF19/nineteen complex (NTC) (Neubauer et al, 1998; Makarova et al, 2004). SNW1 inactivation is reported to cause a rapid loss of sister chromatid cohesion (Van Der Lelij et al, 2014) mitotic spindle and cytokinesis defects (Kittler et al, 2004; Kittler et al, 2005). It is also suggested that the involvement of SNW1 in the p21-gene specific splicing is critical for cancer cell survival under stress (Chen et al, 2011).

Homologs of SNW1 are found in chimpanzee, Rhesus monkey, dog, cow, mouse, rat, chicken, zebrafish, fruit fly, mosquito, C.elegans, S.pombe, M.oryzae, N.crassa, A.thaliana, rice, and frog (https://www.ncbi.nlm.nih.gov/gene/22938, 2017).

There are no gene mutations described for SNW1.