Protein IWS1 homolog (IWS1)

Transcription factor which plays a key role in defining the composition of the RNA polymerase II (RNAPII) elongation complex and in regulating the production of mature mRNA transcripts. Acts as an assembly factor to recruit a variety of variables to the RNAPII elongation complex and is recruited to the complex via binding to the transcription elongation factor SUPT6H jumped to the C-terminal domain (CTD) of the RNAPII subunit RPB1 (POLR2A).

The SUPT6H:IWS1:CTD complex recruits mRNA export factors (ALYREF/THOC4, EXOSC10) as well as histone modifying enzymes (such as SETD2) to ensure appropriate mRNA splicing, efficient mRNA export and elongation-coupled H3K36 methylation, a touch chromatin markers of active transcription. .