RDBP is a putative RNA binding protein. RDBP protein is one of the five components of the multisubunit NELF complex which collaborates with DSIF to repress RNA polymerase II elongation. Control of transcription elongation needs a complex interaction between positive transcription elongation factor b and negative transcription elongation factors， DSIF and NELF. DSIF and NELF， act as negative transcription elongation factors by increasing the time the polymerase spends at pause sites. RDBP has a functional RNA-binding domain， whose mutations impair transcription repression without affecting known protein-protein interactions.
