E3 ubiquitin ligase RNF2 interacts with the S6' proteasomal ATPase subunit and increases the ATP hydrolysis activity of S6'.
We reported previously that the human RNF2 (RING finger protein 2) protein is an E3 ubiquitin ligase that interacts with the human ubiquitin-conjugating enzyme Hip-2/hE2-25K. In the present study, we show that RNF2 interacts with S6' ATPase, a subunit of the proteasomal 19 S regulatory complex. S6' interacts with RNF2 through its N-terminal RING domain, and RNF2 interacts with S6' through its C-terminal region. Interestingly, the RNF2-S6' interaction increases the ATP hydrolysis activity of the S6' protein. Moreover, S6' ATPase activity is highly increased in the presence of ubiquitinated proteins. The present study suggests that the E3 ubiquitin ligase RNF2 might have a dual function: facilitating the ubiquitination of its target substrates and recruiting the substrates to the proteasome. Furthermore, ATP hydrolysis in the E3/proteasome complex might act as an important signal for the protein degradation pathway.
Lee
Sun-Joo
SJ
Graduate School of Biotechnology, Korea University, 1,5-ka Anam-dong, Seoul 136-701, South Korea.
Choi
Dongwon
D
Rhim
Hyangshuk
H
Kang
Seongman
S
D000251:Adenosine Triphosphatases / Q000737:chemistry* / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D063150:Polycomb Repressive Complex 1; D046988:Proteasome Endopeptidase Complex / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021122:Protein Subunits; D012441:Saccharomyces cerevisiae; D015398:Signal Transduction; D013379:Substrate Specificity; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*
D004268:DNA-Binding Proteins; D021122:Protein Subunits; D000255:Adenosine Triphosphate; D063150:Polycomb Repressive Complex 1; C489841:RNF2 protein, human; D044767:Ubiquitin-Protein Ligases; D046988:Proteasome Endopeptidase Complex; D000251:Adenosine Triphosphatases