Oscillations in supercoiling drive circadian gene expression in cyanobacteria

ABSTRACT: The cyanobacterium Synechococcus elongatus PCC 7942 exhibits oscillations in mRNA transcript abundance with 24-hour periodicity under continuous light conditions. The mechanism underlying these oscillations remains elusive â?? neither cis nor trans-factors controlling circadian gene expression phase have been identified. Here we show that the topological status of the chromosome is highly correlated with circadian gene expression state. We also demonstrate that DNA sequence characteristics of genes that appear monotonically activated and monotonically repressed by chromosomal relaxation during the circadian cycle are similar to those of supercoiling responsive genes in E. coli. Furthermore, perturbation of superhelical status within the physiological range elicits global changes in gene ex

ORGANISM(S): Synechococcus elongatus PCC 7942

SUBMITTER: Erin O'Shea 

PROVIDER: E-GEOD-18902 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress