REPAIRtoire - a database of DNA repair pathways

Welcome! Click here to login or here to register.
Home
Proteins
DNA damage
Diseases
Homologs
Pathways
Keywords
Publications
Draw a picture
 
Search
 
Links
Help
Contact





Bujnicki Lab Homepage

"Nuclear localization of human DNA mismatch repair protein exonuclease 1 (hEXO1)."

Knudsen NO, Nielsen FC, Vinther L, Bertelsen R, Holten-Andersen S, Liberti SE, Hofstra R, Kooi K, Rasmussen LJ



Published Jan. 1, 2007 in Nucleic Acids Res volume 35 .

Pubmed ID: 17426132

Abstract:
Human exonuclease 1 (hEXO1) is implicated in DNA mismatch repair (MMR) and mutations in hEXO1 may be associated with hereditary nonpolyposis colorectal cancer (HNPCC). Since the subcellular localization of MMR proteins is essential for proper MMR function, we characterized possible nuclear localization signals (NLSs) in hEXO1. Using fluorescent fusion proteins, we show that the sequence 418KRPR421, which exhibit strong homology to other monopartite NLS sequences, is responsible for correct nuclear localization of hEXO1. This NLS sequence is located in a region that is also required for hEXO1 interaction with hMLH1 and we show that defective nuclear localization of hEXO1 mutant proteins could be rescued by hMLH1 or hMSH2. Both hEXO1 and hMLH1 form complexes with the nuclear import factors importin beta/alpha1,3,7 whereas hMSH2 specifically recognizes importin beta/alpha3. Taken together, we infer that hEXO1, hMLH1 and hMSH2 form complexes and are imported to the nucleus together, and that redundant NLS import signals in the proteins may safeguard nuclear import and thereby MMR activity.


This publication refers to following REPAIRtoire entries:

Proteins


Last modification of this entry: Oct. 6, 2010

Add your own comment!

There is no comment yet.
Welcome stranger! Click here to login or here to register.
Valid HTML 4.01! This site is Emacs powered. Made with Django.