Faculty Opinions recommendation of Two distinct ubiquitin-binding motifs in A20 mediate its anti-inflammatory and cell-protective activities.

Vps9 and Muk1 are guanine nucleotide exchange factors (GEFs) in Saccharomyces cerevisiae that regulate membrane trafficking in the endolysosomal pathway by activating Rab5 GTPases. We show that Vps9 is the primary Rab5 GEF required for biogenesis of late endosomal multivesicular bodies (MVBs). However, only Vps9 (but not Muk1) is required for the formation of aberrant class E compartments that arise upon dysfunction of endosomal sorting complexes required for transport (ESCRTs). ESCRT dysfunction causes ubiquitinated transmembrane proteins to accumulate at endosomes, and we demonstrate that endosomal recruitment of Vps9 is promoted by its ubiquitin-binding CUE domain. Muk1 lacks ubiquitin-binding motifs, but its fusion to the Vps9 CUE domain allows Muk1 to rescue endosome morphology, cargo trafficking, and cellular stress-tolerance phenotypes that result from loss of Vps9 function. These results indicate that ubiquitin binding by the CUE domain promotes Vps9 function in endolysosomal membrane trafficking via promotion of localization.

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Structural Analysis of the Conserved Ubiquitin-binding Motifs (UBMs) of the Translesion Polymerase iota in Complex with Ubiquitin

Journal of Biological Chemistry ◽

10.1074/jbc.m110.135038 ◽

2010 ◽

Vol 286 (2) ◽

pp. 1364-1373 ◽

Cited By ~ 30

Author(s):

Daniel Burschowsky ◽

Fabian Rudolf ◽

Gwénaël Rabut ◽

Torsten Herrmann ◽

Peter Matthias ◽

...

Keyword(s):

Structural Analysis ◽

Binding Motifs ◽

Ubiquitin Binding

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Monoubiquitination by the Fanconi Anemia core complex locks FANCI:FANCD2 on DNA in filamentous arrays

10.1101/862805 ◽

2019 ◽

Cited By ~ 1

Author(s):

Winnie Tan ◽

Sylvie van Twest ◽

Andrew Leis ◽

Rohan Bythell-Douglas ◽

Vincent J. Murphy ◽

...

Keyword(s):

Dna Repair ◽

Fanconi Anemia ◽

Critical Event ◽

Replication Forks ◽

Core Complex ◽

Binding Motifs ◽

Ubiquitin Binding ◽

Functional Consequences ◽

Stalled Replication Forks

AbstractFANCI:FANCD2 monoubiquitination is a critical event for replication fork stabilization by the Fanconi anemia (FA) DNA repair pathway. It has been proposed that at stalled replication forks, monoubiquitinated-FANCD2 serves to recruit DNA repair proteins that contain ubiquitin-binding motifs. Here we have reconstituted the FA pathway in vitro to study functional consequences of FANCI:FANCD2 monoubiquitination. We report that monoubiquitination does not promote any specific exogenous protein:protein interactions, but instead stabilizes FANCI:FANCD2 heterodimers on dsDNA. This locking of FANCI:FANCD2 complex on DNA requires monoubiquitination of only the FANCD2 subunit. We further show that purified monoubiquitinated FANCI:FANCD2 forms filament-like arrays on long dsDNA using electron microscopy. Our results reveal how monoubiquitinated FANCI:FANCD2 is activated upon DNA binding and present new insights to potentially modulate monoubiquitinated FANCI:FANCD2/DNA filaments in FA cells.

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Monoubiquitination by the human Fanconi anemia core complex clamps FANCI:FANCD2 on DNA in filamentous arrays

eLife ◽

10.7554/elife.54128 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 12

Author(s):

Winnie Tan ◽

Sylvie van Twest ◽

Andrew Leis ◽

Rohan Bythell-Douglas ◽

Vincent J Murphy ◽

...

Keyword(s):

Dna Repair ◽

Fanconi Anemia ◽

Critical Event ◽

Core Complex ◽

Binding Motifs ◽

Ubiquitin Binding ◽

Functional Consequences ◽

Cancer Types ◽

Stalled Replication Forks

FANCI:FANCD2 monoubiquitination is a critical event for replication fork stabilization by the Fanconi anemia (FA) DNA repair pathway. It has been proposed that at stalled replication forks, monoubiquitinated-FANCD2 serves to recruit DNA repair proteins that contain ubiquitin-binding motifs. Here, we have reconstituted the FA pathway in vitro to study functional consequences of FANCI:FANCD2 monoubiquitination. We report that monoubiquitination does not promote any specific exogenous protein:protein interactions, but instead stabilizes FANCI:FANCD2 heterodimers on dsDNA. This clamping requires monoubiquitination of only the FANCD2 subunit. We further show using electron microscopy that purified monoubiquitinated FANCI:FANCD2 forms filament-like arrays on long dsDNA. Our results reveal how monoubiquitinated FANCI:FANCD2, defective in many cancer types and all cases of FA, is activated upon DNA binding.

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Ubiquitin-Binding Motifs in REV1 Protein Are Required for Its Role in the Tolerance of DNA Damage

Molecular and Cellular Biology ◽

10.1128/mcb.01118-06 ◽

2006 ◽

Vol 26 (23) ◽

pp. 8892-8900 ◽

Cited By ~ 143

Author(s):

Caixia Guo ◽

Tie-Shan Tang ◽

Marzena Bienko ◽

Joanne L. Parker ◽

Aleksandra B. Bielen ◽

...

Keyword(s):

Dna Damage ◽

Dna Damage Tolerance ◽

Binding Motifs ◽

C Terminus ◽

Ubiquitin Binding ◽

Replication Foci ◽

Induced Mutagenesis ◽

Y Family ◽

Precise Role

ABSTRACT REV1 protein is a eukaryotic member of the Y family of DNA polymerases involved in the tolerance of DNA damage by replicative bypass. The precise role(s) of REV1 in this process is not known. Here we show, by using the yeast two-hybrid assay and the glutathione S-transferase pull-down assay, that mouse REV1 can physically interact with ubiquitin. The association of REV1 with ubiquitin requires the ubiquitin-binding motifs (UBMs) located at the C terminus of REV1. The UBMs also mediate the enhanced association between monoubiquitylated PCNA and REV1. In cells exposed to UV radiation, the association of REV1 with replication foci is dependent on functional UBMs. The UBMs of REV1 are shown to contribute to DNA damage tolerance and damage-induced mutagenesis in vivo.

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