| RRC ID |
81376
|
| Author |
Gaal T, Bratton BP, Sanchez-Vazquez P, Sliwicki A, Sliwicki K, Vegel A, Pannu R, Gourse RL.
|
| Title |
Colocalization of distant chromosomal loci in space in E. coli: a bacterial nucleolus.
|
| Journal |
Genes Dev
|
| Abstract |
The spatial organization of DNA within the bacterial nucleoid remains unclear. To investigate chromosome organization in Escherichia coli, we examined the relative positions of the ribosomal RNA (rRNA) operons in space. The seven rRNA operons are nearly identical and separated from each other by as much as 180° on the circular genetic map, a distance of ≥2 million base pairs. By inserting binding sites for fluorescent proteins adjacent to the rRNA operons and then examining their positions pairwise in live cells by epifluorescence microscopy, we found that all but rrnC are in close proximity. Colocalization of the rRNA operons required the rrn P1 promoter region but not the rrn P2 promoter or the rRNA structural genes and occurred with and without active transcription. Non-rRNA operon pairs did not colocalize, and the magnitude of their physical separation generally correlated with that of their genetic separation. Our results show that E. coli bacterial chromosome folding in three dimensions is not dictated entirely by genetic position but rather includes functionally related, genetically distant loci that come into close proximity, with rRNA operons forming a structure reminiscent of the eukaryotic nucleolus.
|
| Volume |
30(20)
|
| Pages |
2272-2285
|
| Published |
2016-10-15
|
| DOI |
10.1101/gad.290312.116
|
| PII |
30/20/2272
|
| PMID |
27898392
|
| PMC |
PMC5110994
|
| MeSH |
Chromosomes, Bacterial / chemistry
Chromosomes, Bacterial / genetics*
Escherichia coli / genetics*
Nucleolus Organizer Region*
Operon / genetics
Promoter Regions, Genetic / genetics
RNA, Bacterial / genetics
RNA, Bacterial / metabolism
Rec A Recombinases / metabolism
|
| IF |
9.527
|
| Resource |
| Prokaryotes E. coli |
ME10080
ME10081
ME10082
ME10083
ME10084
ME10085
ME10086
ME10087
ME10088
ME10089
ME10090 |
