Proliferating Cell Nuclear Antigen Uses Two Distinct Modes to Move along DNA*
AUTOR(ES)
Kochaniak, Anna B.
FONTE
American Society for Biochemistry and Molecular Biology
RESUMO
Proliferating cell nuclear antigen (PCNA) plays an important role in eukaryotic genomic maintenance by topologically binding DNA and recruiting replication and repair proteins. The ring-shaped protein forms a closed circle around double-stranded DNA and is able to move along the DNA in a random walk. The molecular nature of this diffusion process is poorly understood. We use single-molecule imaging to visualize the movement of individual, fluorescently labeled PCNA molecules along stretched DNA. Measurements of diffusional properties as a function of viscosity and protein size suggest that PCNA moves along DNA using two different sliding modes. Most of the time, the clamp moves while rotationally tracking the helical pitch of the DNA duplex. In a less frequently used second mode of diffusion, the movement of the protein is uncoupled from the helical pitch, and the clamp diffuses at much higher rates.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2719409Documentos Relacionados
- Mammalian proliferating cell nuclear antigen stimulates the processivity of two wheat embryo DNA polymerases.
- A mutational analysis of the yeast proliferating cell nuclear antigen indicates distinct roles in DNA replication and DNA repair.
- Mutations in yeast proliferating cell nuclear antigen define distinct sites for interaction with DNA polymerase delta and DNA polymerase epsilon.
- Calf thymus DNA polymerase delta independent of proliferating cell nuclear antigen (PCNA).
- Requirement of proliferating cell nuclear antigen in RAD6-dependent postreplicational DNA repair.