Abstract
The circadian clock of cyanobacteria is composed of KaiA, KaiB, and KaiC proteins, and the SasA-RpaA two-component system has been implicated in the regulation of one of the output pathways of the clock. In this study, we show that another response regulator that is essential for viability, the RpaA paralog, RpaB, plays a central role in the transcriptional oscillation of clock-regulated genes. In vivo and in vitro analyses revealed that RpaB and not RpaA could specifically bind to the kaiBC promoter, possibly repressing transcription during subjective night. This suggested that binding may be terminated by RpaA to activate gene transcription during subjective day. Moreover, we found that rpoD6 and sigF2, which encode group-2 and group-3 σ factors for RNA polymerase, respectively, were also targets of the RpaAB system, suggesting that a specific group of σ factors can propagate genome-wide transcriptional oscillation. Our findings thus reveal a novel mechanism for a circadian output pathway that is mediated by two paralogous response regulators.
| Original language | English |
|---|---|
| Pages (from-to) | 26321-26327 |
| Number of pages | 7 |
| Journal | Journal of Biological Chemistry |
| Volume | 287 |
| Issue number | 31 |
| DOIs | |
| Publication status | Published - 2012 Jul 27 |
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ASJC Scopus subject areas
- Biochemistry
- Cell Biology
- Molecular Biology
Cite this
RpaB, another response regulator operating circadian clock-dependent transcriptional regulation in Synechococcus elongatus PCC 7942. / Hanaoka, Mitsumasa; Takai, Naoki; Hosokawa, Norimune; Fujiwara, Masayuki; Akimoto, Yuki; Kobori, Nami; Iwasaki, Hideo; Kondo, Takao; Tanaka, Kan.
In: Journal of Biological Chemistry, Vol. 287, No. 31, 27.07.2012, p. 26321-26327.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - RpaB, another response regulator operating circadian clock-dependent transcriptional regulation in Synechococcus elongatus PCC 7942
AU - Hanaoka, Mitsumasa
AU - Takai, Naoki
AU - Hosokawa, Norimune
AU - Fujiwara, Masayuki
AU - Akimoto, Yuki
AU - Kobori, Nami
AU - Iwasaki, Hideo
AU - Kondo, Takao
AU - Tanaka, Kan
PY - 2012/7/27
Y1 - 2012/7/27
N2 - The circadian clock of cyanobacteria is composed of KaiA, KaiB, and KaiC proteins, and the SasA-RpaA two-component system has been implicated in the regulation of one of the output pathways of the clock. In this study, we show that another response regulator that is essential for viability, the RpaA paralog, RpaB, plays a central role in the transcriptional oscillation of clock-regulated genes. In vivo and in vitro analyses revealed that RpaB and not RpaA could specifically bind to the kaiBC promoter, possibly repressing transcription during subjective night. This suggested that binding may be terminated by RpaA to activate gene transcription during subjective day. Moreover, we found that rpoD6 and sigF2, which encode group-2 and group-3 σ factors for RNA polymerase, respectively, were also targets of the RpaAB system, suggesting that a specific group of σ factors can propagate genome-wide transcriptional oscillation. Our findings thus reveal a novel mechanism for a circadian output pathway that is mediated by two paralogous response regulators.
AB - The circadian clock of cyanobacteria is composed of KaiA, KaiB, and KaiC proteins, and the SasA-RpaA two-component system has been implicated in the regulation of one of the output pathways of the clock. In this study, we show that another response regulator that is essential for viability, the RpaA paralog, RpaB, plays a central role in the transcriptional oscillation of clock-regulated genes. In vivo and in vitro analyses revealed that RpaB and not RpaA could specifically bind to the kaiBC promoter, possibly repressing transcription during subjective night. This suggested that binding may be terminated by RpaA to activate gene transcription during subjective day. Moreover, we found that rpoD6 and sigF2, which encode group-2 and group-3 σ factors for RNA polymerase, respectively, were also targets of the RpaAB system, suggesting that a specific group of σ factors can propagate genome-wide transcriptional oscillation. Our findings thus reveal a novel mechanism for a circadian output pathway that is mediated by two paralogous response regulators.
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UR - http://www.scopus.com/inward/citedby.url?scp=84864392477&partnerID=8YFLogxK
U2 - 10.1074/jbc.M111.338251
DO - 10.1074/jbc.M111.338251
M3 - Article
C2 - 22665493
AN - SCOPUS:84864392477
VL - 287
SP - 26321
EP - 26327
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 31
ER -