Display Settings:

Format

Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Mol Biosyst. 2011 Jun;7(6):1874-82. doi: 10.1039/c0mb00355g. Epub 2011 Apr 11.

A novel ubiquitin binding mode in the S. cerevisiae translesion synthesis DNA polymerase η.

Author information

  • 1Department of Chemistry and Biochemistry, 214A Drake Hall, University of Delaware, Newark, DE 19716, USA.

Abstract

The ubiquitin binding zinc finger (UBZ) domain in the C-terminal portion of Polη has been found to interact with ubiquitin. However, the affinity between the Polη UBZ and ubiquitin was shown to be low with a previously reported K(d) of 73-81 μM. This low-affinity binding between Polη UBZ and ubiquitin has been difficult to reconcile with its presumed role in translesion synthesis as suggested by genetic and cell biology studies. In this work, we constructed a minimal S. cerevisiae Polη UBZ domain and probed the Polη UBZ-ubiquitin interaction using a surface plasmon resonance (SPR) technique. Our quantitative binding data between the wild-type or mutant Polη UBZ and ubiquitin revealed an interesting divergence between the Polη UBZ from S. cerevisiae and humans. Moreover, we found that the C-terminal portion of yeast Polη (amino acid 515-632) binds ubiquitin with a much higher affinity than the minimal UBZ domain. Further, distinct ubiquitin-binding kinetics were observed for the C-terminal portion of Polη and the isolated UBZ domain. This observation raised the interesting possibility that the Polη C-terminal portion binds ubiquitin in a novel mode that affords higher affinity. Our findings have broader implication in understanding the generally weak interaction between the known ubiquitin-binding domains and ubiquitin.

PMID:
21483899
[PubMed - indexed for MEDLINE]
PMCID:
PMC3228521
Free PMC Article

Images from this publication.See all images (6)Free text

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Royal Society of Chemistry Icon for PubMed Central
    Loading ...
    Write to the Help Desk