| Structural highlights
Function
[UBP28_HUMAN] Deubiquitinase involved in DNA damage response checkpoint and MYC proto-oncogene stability. Involved in DNA damage induced apoptosis by specifically deubiquitinating proteins of the DNA damage pathway such as CLSPN. Also involved in G2 DNA damage checkpoint, by deubiquitinating CLSPN, and preventing its degradation by the anaphase promoting complex/cyclosome (APC/C). In contrast, it does not deubiquitinate PLK1. Specifically deubiquitinates MYC in the nucleoplasm, leading to prevent MYC degradation by the proteasome: acts by specifically interacting with isoform 1 of FBXW7 (FBW7alpha) in the nucleoplasm and counteracting ubiquitination of MYC by the SCF(FBW7) complex. In contrast, it does not interact with isoform 4 of FBXW7 (FBW7gamma) in the nucleolus, allowing MYC degradation and explaining the selective MYC degradation in the nucleolus.[1] [2] [3] [4]
Publication Abstract from PubMed
Deubiquitinases have emerged as promising drug targets for cancer therapy. The two DUBs USP25 and USP28 share high similarity but vary in their cellular functions. USP28 is known for its tumor-promoting role, whereas USP25 is a regulator of the innate immune system and, recently, a role in tumorigenesis was proposed. We solved the structures of the catalytic domains of both proteins and established substantial differences in their activities. While USP28 is a constitutively active dimer, USP25 presents an auto-inhibited tetramer. Our data indicate that the activation of USP25 is not achieved through substrate or ubiquitin binding. USP25 cancer-associated mutations lead to activation in vitro and in vivo, thereby providing a functional link between auto-inhibition and the cancer-promoting role of the enzyme. Our work led to the identification of significant differences between USP25 and USP28 and provided the molecular basis for the development of new and highly specific anti-cancer drugs.
Differential Oligomerization of the Deubiquitinases USP25 and USP28 Regulates Their Activities.,Sauer F, Klemm T, Kollampally RB, Tessmer I, Nair RK, Popov N, Kisker C Mol Cell. 2019 Mar 22. pii: S1097-2765(19)30140-6. doi:, 10.1016/j.molcel.2019.02.029. PMID:30926243[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Zhang D, Zaugg K, Mak TW, Elledge SJ. A role for the deubiquitinating enzyme USP28 in control of the DNA-damage response. Cell. 2006 Aug 11;126(3):529-42. PMID:16901786 doi:http://dx.doi.org/10.1016/j.cell.2006.06.039
- ↑ Popov N, Wanzel M, Madiredjo M, Zhang D, Beijersbergen R, Bernards R, Moll R, Elledge SJ, Eilers M. The ubiquitin-specific protease USP28 is required for MYC stability. Nat Cell Biol. 2007 Jul;9(7):765-74. Epub 2007 Jun 10. PMID:17558397 doi:http://dx.doi.org/10.1038/ncb1601
- ↑ Popov N, Herold S, Llamazares M, Schulein C, Eilers M. Fbw7 and Usp28 regulate myc protein stability in response to DNA damage. Cell Cycle. 2007 Oct 1;6(19):2327-31. Epub 2007 Jul 26. PMID:17873522
- ↑ Bassermann F, Frescas D, Guardavaccaro D, Busino L, Peschiaroli A, Pagano M. The Cdc14B-Cdh1-Plk1 axis controls the G2 DNA-damage-response checkpoint. Cell. 2008 Jul 25;134(2):256-67. doi: 10.1016/j.cell.2008.05.043. PMID:18662541 doi:http://dx.doi.org/10.1016/j.cell.2008.05.043
- ↑ Sauer F, Klemm T, Kollampally RB, Tessmer I, Nair RK, Popov N, Kisker C. Differential Oligomerization of the Deubiquitinases USP25 and USP28 Regulates Their Activities. Mol Cell. 2019 Mar 22. pii: S1097-2765(19)30140-6. doi:, 10.1016/j.molcel.2019.02.029. PMID:30926243 doi:http://dx.doi.org/10.1016/j.molcel.2019.02.029
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