Tags: Protein.
Transcription elongation factor B polypeptide 3 is a protein that in humans is encoded by the TCEB3 gene.This gene encodes the protein elongin A which is a subunit of the transcription factor B (SIII) complex. The SIII complex is composed of elongins A/A2 B and C. It activates elongation by RNA polymerase II by suppressing transient pausing of the polymerase at many sites within transcription units.