| dc.description.abstract | Retinoblastoma Binding Protein 6 (RBBP6) is a 200 kDa human protein known to play an
essential role in mRNA 3’-end processing, as well as functioning as an E3 ligase to catalyze
ubiquitination and suppression of p53 and other cancer-associated proteins. A RBBP6 knockout
mouse model previously suggested that RBBP6 cooperates with MDM2 in polyubiquitinating
p53, but is not able to ubiquitinate p53 without the assistance of MDM2.
However, unpublished studies from our laboratory suggest that the N-terminal 335 residues of
RBBP6, known as R3, are able to ubiquitinate p53 in full in vitro assays, and that the isolated
RING finger of RBBP6 is able to catalyse ubiquitination of itself, a phenomenon known as
auto-ubiquitination. It is, however, possible that other domains within RBBP6, in particular the
ubiquitin-like DWNN domain situated near to the RING finger, may modulate the autoubiquitination
and substrate-ubiquitination potentials of the complete protein. | en_US |
