The DNA helicase PriA is a key protein for restarting stalled DNA replication forks in bacteria. With 3' to 5' helicase activity, PriA is important in primosome assembly. We used atomic force microscopy (AFM) and specifically employed time-lapse AFM to visualize the interaction of PriA with two DNA substrates. The results show that most of the PriA molecules are observed bound at the fork. However, PriA is capable of translocating over distances of about 400 bp. There is a preference for the long-range translocation of PriA depending on the fork type. For a fork with the nascent leading strand as single-stranded DNA (ssDNA; F4 substrate), PriA translocates preferentially on the parental arm of the fork. For the substrate F14, which contains an additional ssDNA segment between the parental and lagging arms (5 nt gap), PriA translocates on both the parental and lagging strand arms. These data suggest that transient formation of the single-stranded regions during the DNA replication can change the selection of the DNA duplex by PriA. Translocation of the helicase was directly visualized by time-lapse AFM imaging, which revealed that PriA can switch strands during translocation. These novel features of PriA shed new light on the mechanisms of PriA interaction with stalled replication forks.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9596136 | PMC |
| http://dx.doi.org/10.1021/acs.jpcb.0c11225 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
RECQL4 requires PARP1 for recruitment to DNA damage, and PARG dePARylation facilitates its associated role in end joining.
Exp Mol Med
January 2025
Section on DNA Repair, Laboratory of Genetics and Genomics, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA.
RecQ helicases, highly conserved proteins with pivotal roles in DNA replication, DNA repair and homologous recombination, are crucial for maintaining genomic integrity. Mutations in RECQL4 have been associated with various human diseases, including Rothmund-Thomson syndrome. RECQL4 is involved in regulating major DNA repair pathways, such as homologous recombination and nonhomologous end joining (NHEJ).
View Article and Find Full Text PDFPhosphorylation-dependent WRN-RPA interaction promotes recovery of stalled forks at secondary DNA structure.
Nat Commun
January 2025
Mechanisms, Biomarkers and Models Section - Genome Stability Group, Department of Environment and Health, Istituto Superiore di Sanità, Viale Regina Elena, 299 - 00161, Rome, Italy.
The WRN protein is vital for managing perturbed replication forks. Replication Protein A strongly enhances WRN helicase activity in specific in vitro assays. However, the in vivo significance of RPA binding to WRN has largely remained unexplored.
View Article and Find Full Text PDFAdverse multigeneration combined effects of nano-sized plastics and mercury on growth and reproduction in a planktonic copepod Pseudodiaptomus annandalei.
Aquat Toxicol
January 2025
School of Public Health, Chongqing Medical University, Chongqing, 401331, China. Electronic address:
Nano-plastics (NPs) and heavy metals have attracted growing scientific attention because of both pollutants' wide distribution and ecotoxicity. However, the long-term combined toxicity of NPs and mercury (Hg) on planktonic copepods, a crucial presence in marine environments, is unknown. Here, our study aimed to investigate the multigenerational phenotypic responses of the planktonic copepod Pseudodiaptomus annandalei to polystyrene NPs (about 50 nm) and Hg (alone or combined) at environmentally realistic concentrations (23 μg/L for NPs and 1 μg/L for Hg), and the underlying molecular mechanisms were explored.
View Article and Find Full Text PDFThe S-Phase Arrest of Host Cells Caused by an Alpha-Herpesvirus Genome Replication Facilitates Viral Recruitment of RNA Polymerase II to Transcribe Viral Genes.
Cell Prolif
January 2025
Engineering Research Center of Southwest Animal Disease Prevention and Control Technology, Ministry of Education of the People's Republic of China, Chengdu, China.
Herpesviruses rely on host RNA polymerae II (RNA Pol II) for their mRNA transcription, yet the mechanisms of which has been poorly defined, while certain herpesviruses can enhance viral gene transcription by altering the RNA Pol II location, modulating its phosphorylation, or directly interacting with RNA Pol II. However, the influence of herpesviruses on RNA Pol II transcription extends beyond these direct effects. Here, we present a novel mechanism by which the host cell cycle regulates viral gene transcription via RNA Pol II during infection by Anatid Herpesvirus 1 (AnHV-1), an avian alpha-herpesvirus.
View Article and Find Full Text PDFMitochondrial retrograde signaling (MRS) pathways relay the functional status of mitochondria to elicit homeostatic or adaptive changes in nuclear gene expression. Budding yeast have "intergenomic signaling" pathways that sense the amount of mitochondrial DNA (mtDNA) independently of oxidative phosphorylation (OXPHOS), the primary function of genes encoded by mtDNA. However, MRS pathways that sense the amount of mtDNA in mammalian cells remain poorly understood.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!