IWS1 explained

Protein IWS1 homolog also known as interacts with Spt6 (IWS1) is a protein that in humans is encoded by the IWS1 gene.^[1]

IWS1 is a transcription elongation factor. It was first identified during a search for RNA polymerase II-associated elongation factors in yeast; it directly interacts with RNA polymerase II (RNAPII) and is phosphorylated at casein kinase II (CKII) sites.^[2]

The human homolog, which physically interacts with protein arginine methyltransferase 5 (PRMT5), is essential for cell survival.^[3] It also recruits a SET2 histone methyltransferase (Huntingtin-interacting protein HYPB, also known as SETD2) to RNAPII during transcription elongation and is required for H3K36 trimethylation.^[4]

Further reading

• Beausoleil SA, Jedrychowski M, Schwartz D, Elias JE, Villén J, Li J, Cohn MA, Cantley LC, Gygi SP . Large-scale characterization of HeLa cell nuclear phosphoproteins . Proceedings of the National Academy of Sciences of the United States of America . 101 . 33 . 12130–5 . Aug 2004 . 15302935 . 514446 . 10.1073/pnas.0404720101 . 2004PNAS..10112130B . free .
• Nousiainen M, Silljé HH, Sauer G, Nigg EA, Körner R . Phosphoproteome analysis of the human mitotic spindle . Proceedings of the National Academy of Sciences of the United States of America . 103 . 14 . 5391–6 . Apr 2006 . 16565220 . 1459365 . 10.1073/pnas.0507066103 . 2006PNAS..103.5391N . free .
• Ling Y, Smith AJ, Morgan GT . A sequence motif conserved in diverse nuclear proteins identifies a protein interaction domain utilised for nuclear targeting by human TFIIS . Nucleic Acids Research . 34 . 8 . 2219–29 . 2006 . 16648364 . 1450333 . 10.1093/nar/gkl239 .
• Beausoleil SA, Villén J, Gerber SA, Rush J, Gygi SP . A probability-based approach for high-throughput protein phosphorylation analysis and site localization . Nature Biotechnology . 24 . 10 . 1285–92 . Oct 2006 . 16964243 . 10.1038/nbt1240 . 14294292 .
• Olsen JV, Blagoev B, Gnad F, Macek B, Kumar C, Mortensen P, Mann M . Global, in vivo, and site-specific phosphorylation dynamics in signaling networks . Cell . 127 . 3 . 635–48 . Nov 2006 . 17081983 . 10.1016/j.cell.2006.09.026 . 7827573 . free .
• Liu Z, Zhou Z, Chen G, Bao S . A putative transcriptional elongation factor hIws1 is essential for mammalian cell proliferation . Biochemical and Biophysical Research Communications . 353 . 1 . 47–53 . Feb 2007 . 17184735 . 10.1016/j.bbrc.2006.11.133 .
• Yoh SM, Cho H, Pickle L, Evans RM, Jones KA . The Spt6 SH2 domain binds Ser2-P RNAPII to direct Iws1-dependent mRNA splicing and export . Genes & Development . 21 . 2 . 160–74 . Jan 2007 . 17234882 . 1770899 . 10.1101/gad.1503107 .

Notes and References

1. Web site: Entrez Gene: IWS1 IWS1 homolog (S. cerevisiae).
2. Krogan NJ, Kim M, Ahn SH, Zhong G, Kobor MS, Cagney G, Emili A, Shilatifard A, Buratowski S, Greenblatt JF . RNA polymerase II elongation factors of Saccharomyces cerevisiae: a targeted proteomics approach . Molecular and Cellular Biology . 22 . 20 . 6979–92 . Oct 2002 . 12242279 . 139818 . 10.1128/MCB.22.20.6979-6992.2002 .
3. Liu Z, Zhou Z, Chen G, Bao S . A putative transcriptional elongation factor hIws1 is essential for mammalian cell proliferation . Biochemical and Biophysical Research Communications . 353 . 1 . 47–53 . Feb 2007 . 17184735 . 10.1016/j.bbrc.2006.11.133 .
4. Yoh SM, Lucas JS, Jones KA . The Iws1:Spt6:CTD complex controls cotranscriptional mRNA biosynthesis and HYPB/Setd2-mediated histone H3K36 methylation . Genes & Development . 22 . 24 . 3422–34 . Dec 2008 . 19141475 . 2607075 . 10.1101/gad.1720008 .