A new protein domain for binding to DNA through the minor groove.
AUTOR(ES)
Freire, R
RESUMO
Protein p6 of the Bacillus subtilis phage phi 29 binds with low sequence specificity to DNA through the minor groove, forming a multimeric nucleoprotein complex that activates the initiation of phi 29 DNA replication. Deletion analysis suggested that the N-terminal part of protein p6, predicted to form an amphipathic alpha-helix, is involved in DNA binding. We have constructed site-directed mutants at the polar side of the putative alpha-helix. DNA binding and activation of initiation of phi 29 DNA replication were impaired in most of the mutant proteins obtained. A 19 amino acid peptide comprising the N-terminus of protein p6 interacted with a DNA fragment containing high-affinity signals for protein p6 binding with approximately 50-fold higher affinity than the peptide corresponding to an inactive mutant. Both wild-type peptide and protein p6 recognized the same sequences in this DNA fragment. This result, together with distamycin competition experiments, suggested that the wild-type peptide also binds to DNA through the minor groove. In addition, CD spectra of the wild-type peptide showed an increase in the alpha-helical content when bound to DNA. All these results indicate that an alpha-helical structure located in the N-terminal region of protein p6 is involved in DNA binding through the minor groove.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=395362Documentos Relacionados
- Calicheamicin-DNA complexes: warhead alignment and saccharide recognition of the minor groove.
- Binding of matrix attachment regions to lamin polymers involves single-stranded regions and the minor groove.
- Myc/Max and other helix-loop-helix/leucine zipper proteins bend DNA toward the minor groove.
- A new minor groove binding asymmetric cyanine reporter dye for real-time PCR
- A novel assay to determine the sequence preference and affinity of DNA minor groove binding compounds