|
| Status |
Public on Sep 13, 2018 |
| Title |
A bacterial chromosome structuring protein binds overtwisted DNA to stimulate type II topoisomerases and enable DNA replication |
| Organism |
Caulobacter vibrioides NA1000 |
| Experiment type |
Expression profiling by high throughput sequencing
Genome binding/occupancy profiling by high throughput sequencing
|
| Summary |
When DNA is unwound during replication, it becomes overtwisted and forms positive supercoils in front of the translocating DNA polymerase. Unless removed or dissipated, this superhelical tension can impede replication elongation. Topoisomerases, including gyrase and topoisomerase IV in bacteria, are required to relax positive supercoils ahead of DNA polymerase, but may not be sufficient for replication. Here, we find that GapR, a chromosome structuring protein in Caulobacter crescentus, is required to complete DNA replication. GapR associates in vivo with positively supercoiled chromosomal DNA, and our biochemical and structural studies demonstrate that GapR forms a dimer-of-dimers that fully encircles overtwisted DNA. Further, we show that GapR stimulates gyrase and topo IV to relax positive supercoils, thereby enabling DNA replication. Analogous chromosome structuring proteins that locate to the overtwisted DNA in front of replication forks may be present in other organisms, similarly helping to recruit and stimulate topoisomerases during DNA replication.
|
| |
|
| Overall design |
Sequencing experiments from Caulobacter crescentus CB15N wild-type, GapR-3xFLAG, and GapR-depleted cells. (i) RNA-seq after GapR depletion, (ii) GapR-3xFLAG ChIP-seq, (iii) cell-cycle DNA-seq after GapR depletion.
|
| |
|
| Contributor(s) |
Guo MS, Haakonsen DL, Zeng W, Schumacher MA, Laub MT |
| Citation(s) |
30220456 |
| NIH grant(s) |
| Grant ID |
Grant title |
Affiliation |
Name |
| R01 GM082899 |
Cell cycle regulation and chromosome organization in Caulobacter crescentus |
MASSACHUSETTS INSTITUTE OF TECHNOLOGY |
Michael Laub |
| R01 GM115563 |
Assembly and partition mechanism of Walker-box based segregation machinery |
DUKE UNIVERSITY |
Maria Schumacher |
|
| |
| Submission date |
Jun 29, 2017 |
| Last update date |
Jul 25, 2021 |
| Contact name |
Monica S Guo |
| E-mail(s) |
msguo@uw.edu
|
| Organization name |
University of Washington
|
| Department |
Microbiology
|
| Lab |
Guo
|
| Street address |
750 Republican St
|
| City |
Seattle |
| State/province |
WA |
| ZIP/Postal code |
98109 |
| Country |
USA |
| |
|
| Platforms (2) |
| GPL18276 |
Illumina HiSeq 2000 (Caulobacter crescentus NA1000) |
| GPL20784 |
Illumina MiSeq (Caulobacter crescentus NA1000) |
|
| Samples (21)
|
|
| Relations |
| BioProject |
PRJNA392436 |
| SRA |
SRP110755 |
Less...
More...