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PROSITE documentation PDOC51157Zinc finger UBR-type profile
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PURL: https://purl.expasy.org/prosite/documentation/PDOC51157
It has been observed that the identity of N-terminal residues of a protein is related to the half life of the protein. This observation yields a rule, called the N-end rule [1]. Similar but distinct versions of the N-end rule operate in all organisms examined, from mammals to fungi and bacteria. In eukaryotes, the N-end rule pathway is a part of the ubiquitin degradation system. Some proteins that have a very short half life contain a specific motif at their N-terminus, the N-degron. It consists of a destabilizing N-terminal residue and an internal Lys, which is the site of poly-Ub chain [1,2].
The UBR1 protein was shown to bind specifically to proteins bearing N-terminal residues that are destabilizing according to the N-end rule, but not to otherwise identical proteins bearing stabilizing N-terminal residues [3]. UBR1 contain an N-terminal conserved region (the UBR-type zinc finger) which is also found in various proteins implicated in N-degron recognition. The UBR-type zinc finger defines a unique E3 class, most likely N-degron specific [4].
The profile we developed covers the whole UBR-type zinc finger.
Note:The UBR-type zinc finger is also known as the UBR box motif [4].
Last update:October 2005 / First entry.
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PROSITE method (with tools and information) covered by this documentation:
| 1 | Authors | Varshavsky A. |
| Title | The N-end rule: functions, mysteries, uses. | |
| Source | Proc. Natl. Acad. Sci. U.S.A. 93:12142-12149(1996). | |
| PubMed ID | 8901547 |
| 2 | Authors | Suzuki T. Varshavsky A. |
| Title | Degradation signals in the lysine-asparagine sequence space. | |
| Source | EMBO J. 18:6017-6026(1999). | |
| PubMed ID | 10545113 | |
| DOI | 10.1093/emboj/18.21.6017 |
| 3 | Authors | Xie Y. Varshavsky A. |
| Title | The E2-E3 interaction in the N-end rule pathway: the RING-H2 finger of E3 is required for the synthesis of multiubiquitin chain. | |
| Source | EMBO J. 18:6832-6844(1999). | |
| PubMed ID | 10581257 | |
| DOI | 10.1093/emboj/18.23.6832 |
| 4 | Authors | Tasaki T. Mulder L.C. Iwamatsu A. Lee M.J. Davydov I.V. Varshavsky A. Muesing M. Kwon Y.T. |
| Title | A family of mammalian E3 ubiquitin ligases that contain the UBR box motif and recognize N-degrons. | |
| Source | Mol. Cell. Biol. 25:7120-7136(2005). | |
| PubMed ID | 16055722 | |
| DOI | 10.1128/MCB.25.16.7120-7136.2005 |
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