Ring-finger proteins

Thomas Cbl is a ring finger protein which is involved in down-regulation of the receptor. This didn t fall out of the original screen. Are there mutants in Cbl as well ... 

Remarkably, at the same time, several groups independently determined that there was a previously undiscovered component to the SCF complex - a small non-canonical RING finger protein known variably as Rbxl, Rod or Hrtl [36-... 

Perhaps, analogous to Bardl, MdmX may modulate the E3 activity of Mdm2 towards p53 through dimerization (see below). Ironically, PML (promyleocytic 7eu-kemia), one of the first RING finger proteins to be characterized has, to date, not shown E3 activity (see below). 

The Snurf (small nuclear RING finger) protein has E3 activity using at least six different E2s [80], all of which appear to have different patterns of ubiquitin modification. On the other hand A07 and Brcal only appear active with members of the... 

UbcH5 family [21, 80, 81]. Presumably, the ability to interact productively with a smaller number of E2s will restrict E3 activity to situations where the RING finger protein and the E2 are co-expressed and co-localized. 

Other Protein-Protein Interaction Motifs in RING finger Proteins... 

RING finger proteins may have other domains associated with signal transduction, such as SH3 and STAT domains and domains that bind and effect hydrolysis of nucleotides in signal transduction or for other purposes. These include ATPases, ATP synthases, serine/threonine kinases, GTP-binding domains, ADP-ribosylation domains and AAA-superfamily ATPases (http //home.cancer.gov/lpds/weissman). 

Yeast RadlSp functions with the RING finger protein RadSp in error-free post-replicative DNA repair. 

Found in the transcriptional repressor NF-Xl, a PHD finger/RING finger protein. 

The coiled-coil domain frequently mediates hetero- or homodimerization. About two-thirds of a large number of TRIM proteins tested dimerize [125]. As a number of other RING finger proteins either homo- or hererodimerize, dimerization may facilitate optimal E3 activity of TRIMs. While most proteins that carry the TRIM... 

Families of RING finger proteins play important roles in cell regulation, signal transduction and apoptosis. Some of the more prominent families are the Siahs, lAPs, TRAFs, and Cbls (Figure 4.4). Short summaries of these are presented below. 

Regulation of p53 by Mdm2 and other RING finger Proteins 77... 

Ulrich, H. D. and S. Jentsch, Two Ring-finger proteins mediate cooperation between ubiquitin-conjugating enzymes in DNA repair. EmboJ, 2000, 19(13), 3388-97. 

Didier, C., etal., RNF5, a Ring-finger protein that regulates cell motility by targeting paxillin ubiquitination and altered localization. Mol Cell Biol,... 

Horie, K., et al.. Estrogen-responsive Ring-finger protein controls breast cancer growth. J Steroid Biochem Mol Biol, 2003, 85(2-5), 101-4. 

Ito, K., et al., N-Terminally extended human ubiquitin-conjugating enzymes (E2s) mediate the ubiqui-tination of RING finger proteins, ARA54 and RNE8. Eur J Biochem,... 

Aguilera, M., et ah, Ariadne-1 a vital Drosophila gene is required in development and defines a new conserved family of ring-finger proteins. Genetics, 2000, 155(3), 1231-44. 

Hwang, W. W., Venkatasubrahmanyam, S., Ianculescu, a. G., Tong, A., Boone, C., and Madhani, H. D. A conserved RING finger protein required for histone H2B monoubiquitination and cell size control. Mol. Cell 2003, 11, 261-66. 

The major function of the Cull CTD is to recruit the RING-finger protein Rbxl. The CTD binds Rbxl through two distinct interfaces (Figure 7.2). One involves an... 

JoAZEiRO, C. A. and Weissman, A. M. RING finger proteins mediators of ubiquitin ligase activity. Cell 2000, 102, 549-52. 

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