Essential component of the NELF complex, a complex that negatively regulates the elongation of transcription by RNA polymerase II . The NELF complex, which acts via an association with the DSIF complex and causes transcriptional pausing, is counteracted by the P-TEFb kinase complex .
(Microbial infection) The NELF complex is involved in HIV-1 latency possibly involving recruitment of PCF11 to paused RNA polymerase II.
Subcellular locations: Nucleus
Widely expressed. Expressed in heart, brain, lung, placenta, liver, skeletal and cardiac muscle, adrenal, thyroid, kidney and pancreas.