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4xyz

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Revision as of 00:21, 6 June 2019

Crystal structure of K33 linked di-Ubiquitin

Structural highlights

4xyz is a 2 chain structure with sequence from Bos taurus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:	, , ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[UBC_BOVIN] Ubiquitin: Exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiquitin (linear polyubiquitin chains). Polyubiquitin chains, when attached to a target protein, have different functions depending on the Lys residue of the ubiquitin that is linked: Lys-6-linked may be involved in DNA repair; Lys-11-linked is involved in ERAD (endoplasmic reticulum-associated degradation) and in cell-cycle regulation; Lys-29-linked is involved in lysosomal degradation; Lys-33-linked is involved in kinase modification; Lys-48-linked is involved in protein degradation via the proteasome; Lys-63-linked is involved in endocytosis, DNA-damage responses as well as in signaling processes leading to activation of the transcription factor NF-kappa-B. Linear polymer chains formed via attachment by the initiator Met lead to cell signaling. Ubiquitin is usually conjugated to Lys residues of target proteins, however, in rare cases, conjugation to Cys or Ser residues has been observed. When polyubiquitin is free (unanchored-polyubiquitin), it also has distinct roles, such as in activation of protein kinases, and in signaling (By similarity).

Publication Abstract from PubMed

Ubiquitylation regulates a multitude of biological processes and this versatility stems from the ability of ubiquitin to form topologically different polymers of eight different linkage types. While some linkages have been studied in detail, other linkage types including Lys33-linked polyubiquitin are poorly understood. Here we identify an enzymatic system for the large-scale assembly of Lys33 chains by combining the HECT (homologous to the E6-AP carboxyl terminus) E3 ligase AREL1 (apoptosis-resistant E3 ubiquitin protein ligase 1) with linkage selective deubiquitinases (DUBs). Moreover, this first characterisation of the chain selectivity of AREL1 indicates its preference for assembling Lys33- and Lys11-linked ubiquitin chains. Intriguingly, the crystal structure of Lys33-linked diubiquitin (diUb) reveals that it adopts a compact conformation very similar to that observed for Lys11-linked diUb. In contrast, crystallographic analysis of Lys33-linked triUb reveals a more extended conformation. These two distinct conformational states of Lys33-linked polyUb may be selectively recognized by ubiquitin binding domains and enzymes of the ubiquitin system. Importantly, our work provides a method to assemble Lys33-linked polyubiquitin that will allow further characterization of this atypical chain type.

Assembly and structure of Lys33-linked polyubiquitin reveals distinct conformations.,Kristariyanto YA, Choi SY, Abdul Rehman SA, Ritorto MS, Campbell DG, Morrice NA, Toth R, Kulathu Y Biochem J. 2015 Feb 27. PMID:25723849^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Kristariyanto YA, Choi SY, Abdul Rehman SA, Ritorto MS, Campbell DG, Morrice NA, Toth R, Kulathu Y. Assembly and structure of Lys33-linked polyubiquitin reveals distinct conformations. Biochem J. 2015 Feb 27. PMID:25723849 doi:http://dx.doi.org/10.1042/BJ20141502

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4xyz"

@@ Line 1: / Line 1: @@
 ==Crystal structure of K33 linked di-Ubiquitin==
-<StructureSection load='4xyz' size='340' side='right' caption='[[4xyz]], [[Resolution|resolution]] 1.65&Aring;' scene=''>
+<StructureSection load='4xyz' size='340' side='right'caption='[[4xyz]], [[Resolution|resolution]] 1.65&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[4xyz]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4XYZ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4XYZ FirstGlance]. <br>
@@ Line 26: / Line 26: @@
 </StructureSection>
 [[Category: Bos taurus]]
+[[Category: Large Structures]]
 [[Category: Campbell, D G]]
 [[Category: Choi, S Y]]

4xyz

From Proteopedia

Revision as of 00:21, 6 June 2019

Crystal structure of K33 linked di-Ubiquitin

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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