Function
HUL4 is a probable E3 ubiquitin-protein ligase. It is a component of the TRAMP (TRF4) complex, which possesses poly(A) RNA polymerase activity. This complex plays a crucial role in post-transcriptional quality control by limiting inappropriate expression of genetic information. The polyadenylation function of TRAMP is essential for the degradative activity of the exosome on various nuclear RNA substrates.