1
|
Oh GS, Yoo JS, Park JH, Roe JH. Activity modulation of anti-sigma factor via cysteine alkylation in Actinobacteria. Mol Microbiol 2021; 117:539-550. [PMID: 34927290 DOI: 10.1111/mmi.14868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/15/2021] [Accepted: 12/15/2021] [Indexed: 11/29/2022]
Abstract
σR (SigR) is an alternative sigma factor that enables gene expression in Streptomyces coelicolor to cope with thiol oxidation and antibiotic stresses. Its activity is repressed by a zinc-containing anti-sigma (ZAS) factor RsrA that senses thiol oxidants and electrophiles. Inactivation of RsrA by disulfide formation has been well studied. Here we investigated another pathway of RsrA inactivation by electrophiles. Mass spectrometry revealed alkylation of RsrA in vivo by N-ethylmaleimide (NEM) at C61 and C62 located in the C-terminal loop. Substitution mutation (C61S/C62S) in RsrA decreased the induction of σR target genes by electrophiles and made cells more sensitive to electrophiles. In contrast to stable protein of oxidized RsrA, alkylated RsrA is subjected to degradation partly mediated by ClpP proteases. RsrA2, a redox-sensitive homolog of RsrA in S. coelicolor lacking cysteine in the terminal loop, did not respond to electrophiles. However, redox-sensitive RsrA homologs in other Actinobacteria also harboring terminal loop cysteines all responded to electrophiles. These results indicate that the activity of RsrA can be modulated via cysteine alkylation, apart from disulfide formation of zinc-coordinating cysteines. This pathway expands the spectrum of signals that the σR -RsrA system can sense and reveals another intricate regulatory layer for optimal survival of Actinobacteria.
Collapse
Affiliation(s)
- Gyeong-Seok Oh
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, Korea
| | - Ji-Sun Yoo
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, Korea
| | - Joo-Hong Park
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, Korea
| | - Jung-Hye Roe
- School of Biological Sciences and Institute of Microbiology, Seoul National University, Seoul, Korea
| |
Collapse
|
2
|
Takasugi N, Hiraoka H, Nakahara K, Akiyama S, Fujikawa K, Nomura R, Furuichi M, Uehara T. The Emerging Role of Electrophiles as a Key Regulator for Endoplasmic Reticulum (ER) Stress. Int J Mol Sci 2019; 20:E1783. [PMID: 30974903 PMCID: PMC6480251 DOI: 10.3390/ijms20071783] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 03/28/2019] [Accepted: 04/08/2019] [Indexed: 12/13/2022] Open
Abstract
The unfolded protein response (UPR) is activated by the accumulation of misfolded proteins in the endoplasmic reticulum (ER), which is called ER stress. ER stress sensors PERK, IRE1, and ATF6 play a central role in the initiation and regulation of the UPR; they inhibit novel protein synthesis and upregulate ER chaperones, such as protein disulfide isomerase, to remove unfolded proteins. However, when recovery from ER stress is difficult, the UPR pathway is activated to eliminate unhealthy cells. This signaling transition is the key event of many human diseases. However, the precise mechanisms are largely unknown. Intriguingly, reactive electrophilic species (RES), which exist in the environment or are produced through cellular metabolism, have been identified as a key player of this transition. In this review, we focused on the function of representative RES: nitric oxide (NO) as a gaseous RES, 4-hydroxynonenal (HNE) as a lipid RES, and methylmercury (MeHg) as an environmental organic compound RES, to outline the relationship between ER stress and RES. Modulation by RES might be a target for the development of next-generation therapy for ER stress-associated diseases.
Collapse
Affiliation(s)
- Nobumasa Takasugi
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Hideki Hiraoka
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Kengo Nakahara
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Shiori Akiyama
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Kana Fujikawa
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Ryosuke Nomura
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Moeka Furuichi
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| | - Takashi Uehara
- Department of Medicinal Pharmacology, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan.
| |
Collapse
|
3
|
Lee KL, Yoo JS, Oh GS, Singh AK, Roe JH. Simultaneous Activation of Iron- and Thiol-Based Sensor-Regulator Systems by Redox-Active Compounds. Front Microbiol 2017; 8:139. [PMID: 28210250 PMCID: PMC5288332 DOI: 10.3389/fmicb.2017.00139] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 01/19/2017] [Indexed: 12/21/2022] Open
Abstract
Bacteria in natural habitats are exposed to myriad redox-active compounds (RACs), which include producers of reactive oxygen species (ROS) and reactive electrophile species (RES) that alkylate or oxidize thiols. RACs can induce oxidative stress in cells and activate response pathways by modulating the activity of sensitive regulators. However, the effect of a certain compound on the cell has been investigated primarily with respect to a specific regulatory pathway. Since a single compound can exert multiple chemical effects in the cell, its effect can be better understood by time-course monitoring of multiple sensitive regulatory pathways that the compound induces. We investigated the effect of representative RACs by monitoring the activity of three sensor-regulators in the model actinobacterium Streptomyces coelicolor; SoxR that senses reactive compounds directly through oxidation of its [2Fe–2S] cluster, CatR/PerR that senses peroxides through bound iron, and an anti-sigma factor RsrA that senses RES via disulfide formation. The time course and magnitude of induction of their target transcripts were monitored to predict the chemical activities of each compound in S. coelicolor. Phenazine methosulfate (PMS) was found to be an effective RAC that directly activated SoxR and an effective ROS-producer that induced CatR/PerR with little thiol-perturbing activity. p-Benzoquinone was an effective RAC that directly activated SoxR, with slower ROS-producing activity, and an effective RES that induced the RsrA-SigR system. Plumbagin was an effective RAC that activated SoxR, an effective ROS-producer, and a less agile but effective RES. Diamide was an RES that effectively formed disulfides and a weak RAC that activated SoxR. Monobromobimane was a moderately effective RES and a slow producer of ROS. Interestingly, benzoquinone induced the SigR system by forming adducts on cysteine thiols in RsrA, revealing a new pathway to modulate RsrA activity. Overall, this study showed that multiple chemical activities of a reactive compound can be conveniently monitored in vivo by examining the temporal response of multiple sensitive regulators in the cell to reveal novel activities of the chemicals.
Collapse
Affiliation(s)
- Kang-Lok Lee
- School of Biological Sciences and Institute of Microbiology, Seoul National University Seoul, South Korea
| | - Ji-Sun Yoo
- School of Biological Sciences and Institute of Microbiology, Seoul National University Seoul, South Korea
| | - Gyeong-Seok Oh
- School of Biological Sciences and Institute of Microbiology, Seoul National University Seoul, South Korea
| | - Atul K Singh
- School of Biological Sciences and Institute of Microbiology, Seoul National University Seoul, South Korea
| | - Jung-Hye Roe
- School of Biological Sciences and Institute of Microbiology, Seoul National University Seoul, South Korea
| |
Collapse
|