Back to Search
Start Over
Regulation of UMSBP activities through redox-sensitive protein domains.
- Source :
-
Nucleic acids research [Nucleic Acids Res] 2009 Jan; Vol. 37 (1), pp. 279-88. Date of Electronic Publication: 2008 Nov 27. - Publication Year :
- 2009
-
Abstract
- UMSBP is a CCHC-type zinc finger protein, which functions during replication initiation of kinetoplast DNA minicircles and the segregation of kinetoplast DNA networks. Interactions of UMSBP with origin sequences, as well as the protein oligomerization, are affected by its redox state. Reduction yields UMSBP monomers and activates its binding to DNA, while oxidation drives UMSBP oligomerization and impairs its DNA-binding activity. Kinetics analyses of UMSBP-DNA interactions revealed that redox affects the association of free UMSBP with the DNA, but has little effect on its dissociation from the nucleoprotein complex. A previously proposed model, suggesting that binding of DNA is regulated via the reversible interconversions of active UMSBP monomers and inactive oligomers, was challenged here, revealing that the two redox-driven processes are not interrelated. No correlation could be observed between DNA-binding inhibition and UMSBP oligomerization, upon oxidation of UMSBP. Moreover, while the presence of zinc ions was found to be essential for the interaction of UMSBP with DNA, UMSBP oligomerization occurred through zinc-depleted, unfolded zinc finger domains. Site directed mutagenesis analysis of UMSBP suggested that its unique methionine residue, which can be oxidized into methionine sulfoxide, is not involved in the redox-mediated regulation of UMSBP-DNA interactions.
- Subjects :
- Amino Acid Sequence
Animals
Crithidia fasciculata genetics
Crithidia fasciculata metabolism
Cysteine chemistry
DNA, Kinetoplast chemistry
DNA-Binding Proteins metabolism
Methionine chemistry
Molecular Sequence Data
Nucleoproteins metabolism
Oxidation-Reduction
Protein Structure, Tertiary
Protozoan Proteins metabolism
Sequence Homology, Amino Acid
Zinc Fingers
DNA, Kinetoplast metabolism
DNA-Binding Proteins chemistry
Protozoan Proteins chemistry
Replication Origin
Subjects
Details
- Language :
- English
- ISSN :
- 1362-4962
- Volume :
- 37
- Issue :
- 1
- Database :
- MEDLINE
- Journal :
- Nucleic acids research
- Publication Type :
- Academic Journal
- Accession number :
- 19039000
- Full Text :
- https://doi.org/10.1093/nar/gkn927