transcription elongation factor SPT5; hSPT5; DRB sensitivity-inducing factor large subunit; DSIF large subunit; DSIF p160; Tat-cotransactivator 1 protein; Tat-CT1 protein (SUPT5H, SPT5, SPT5H)

Function

• component of the DSIF complex
• component of a complex which is at least composed of HTATSF1/Tat-SF1, the P-TEFb complex components CDK9 & CCNT1, RNA polymerase 2, SUPT5H, & NCL/nucleolin
• methylated by PRMT1/HRMT1L2 & PRMT5/SKB1
• methylation negatively regulates interaction with P-TEFb & RNA polymerase 2
• phosphorylation by P-TEFb alleviates transcriptional pausing & can stimulate transcriptional elongation from the HIV-1 LTR
• P-TEFb dependent phosphorylation is stimulated by the HIV-1 Tat protein
• phosphorylation may also stimulate interaction with PIN1
• bulk phosphorylation occurs predominantly in mitosis

Structure

• belongs to the SPT5 family
• contains 5 KOW domains

Compartment

nucleus

Alternative splicing

named isoforms=2

Expression

ubiquitously expressed

More general terms

• transcription elongation factor
• phosphoprotein

Component of

• DRB sensitivity-inducing factor complex (DSIF complex, DSIF)

Database

• OMIM: https://mirror.omim.org/entry/602102
• UniProt: http://www.uniprot.org/uniprot/O00267.html