Functional studies on the candidate ATPase domains of Saccharomyces cerevisiae MutLalpha.
Saccharomyces cerevisiae MutL homologues Mlh1p and Pms1p form a heterodimer, termed MutLalpha, that is required for DNA mismatch repair after mismatch binding by MutS homologues. Recent sequence and structural studies have placed the NH(2) termini of MutL homologues in a new family of ATPases. To address the functional significance of ... this putative ATPase activity in MutLalpha, we mutated conserved motifs for ATP hydrolysis and ATP binding in both Mlh1p and Pms1p and found that these changes disrupted DNA mismatch repair in vivo. Limited proteolysis with purified recombinant MutLalpha demonstrated that the NH(2) terminus of MutLalpha undergoes conformational changes in the presence of ATP and nonhydrolyzable ATP analogs. Furthermore, two-hybrid analysis suggested that these ATP-binding-induced conformational changes promote an interaction between the NH(2) termini of Mlh1p and Pms1p. Surprisingly, analysis of specific mutants suggested differential requirements for the ATPase motifs of Mlh1p and Pms1p during DNA mismatch repair. Taken together, these results suggest that MutLalpha undergoes ATP-dependent conformational changes that may serve to coordinate downstream events during yeast DNA mismatch repair.
Mesh Terms:
Adaptor Proteins, Signal Transducing, Adenine, Adenosine Triphosphatases, Adenosine Triphosphate, Amino Acid Sequence, Bacterial Proteins, Carrier Proteins, DNA Mutational Analysis, DNA Repair, Escherichia coli, Escherichia coli Proteins, Fungal Proteins, Hydrolysis, Models, Biological, Molecular Sequence Data, Plasmids, Protein Binding, Protein Conformation, Recombinant Proteins, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sequence Homology, Amino Acid, Two-Hybrid System Techniques, beta-Galactosidase
Adaptor Proteins, Signal Transducing, Adenine, Adenosine Triphosphatases, Adenosine Triphosphate, Amino Acid Sequence, Bacterial Proteins, Carrier Proteins, DNA Mutational Analysis, DNA Repair, Escherichia coli, Escherichia coli Proteins, Fungal Proteins, Hydrolysis, Models, Biological, Molecular Sequence Data, Plasmids, Protein Binding, Protein Conformation, Recombinant Proteins, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sequence Homology, Amino Acid, Two-Hybrid System Techniques, beta-Galactosidase
Mol. Cell. Biol.
Date: Sep. 01, 2000
PubMed ID: 10938116
View in: Pubmed Google Scholar
Download Curated Data For This Publication
18463
Switch View:
- Interactions 1