1
|
Mahbub M, Mullineaux CW. Locations of membrane protein production in a cyanobacterium. J Bacteriol 2023; 205:e0020923. [PMID: 37787518 PMCID: PMC10601611 DOI: 10.1128/jb.00209-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 08/28/2023] [Indexed: 10/04/2023] Open
Abstract
Cyanobacteria show an unusually complex prokaryotic cell structure including a distinct intracytoplasmic membrane system, the thylakoid membranes that are the site of the photosynthetic light reactions. The thylakoid and plasma membranes have sharply distinct proteomes, but the mechanisms that target proteins to a specific membrane remain poorly understood. Here, we investigate the locations of translation of thylakoid and plasma membrane proteins in the model unicellular cyanobacterium Synechococcus elongatus PCC 7942. We use fluorescent in situ hybridization to probe the locations of mRNAs encoding membrane-integral proteins, plus Green Fluorescent Protein tagging of the RplL subunit to reveal the location of ribosomes under different conditions. We show that membrane-integral thylakoid and plasma membrane proteins are translated in different locations. Thylakoid membrane proteins are translated in patches at the innermost thylakoid membrane surface facing the nucleoid. However, different proteins are translated in different patches, even when they are subunits of the same multiprotein complex. This implies that translation is distributed over the proximal thylakoid surface, with newly inserted proteins migrating within the membrane prior to incorporation into complexes. mRNAs encoding plasma membrane proteins form patches at the plasma membrane. Ribosomes can be observed at similar locations near the thylakoid and plasma membranes, with more ribosomes near the plasma membrane when conditions force rapid production of plasma membrane proteins. There must be routes for ribosomes and mRNAs past the thylakoids to the plasma membrane. We infer a system to chaperone plasma membrane mRNAs to prevent their translation prior to arrival at the correct membrane. IMPORTANCE Cyanobacteria have a complex and distinct membrane system within the cytoplasm, the thylakoid membranes that house the photosynthetic light reactions. The thylakoid and plasma membranes contain distinct sets of proteins, but the steps that target proteins to the two membranes remain unclear. Knowledge of the protein sorting rules will be crucial for the biotechnological re-engineering of cyanobacterial cells, and for understanding the evolutionary development of the thylakoids. Here, we probe the subcellular locations of the mRNAs that encode cyanobacterial membrane proteins and the ribosomes that translate them. We show that thylakoid and plasma membrane proteins are produced at different locations, providing the first direct evidence for a sorting mechanism that operates prior to protein translation.
Collapse
Affiliation(s)
- Moontaha Mahbub
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
- Department of Botany, Jagannath University, Dhaka, Bangladesh
| | - Conrad W. Mullineaux
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
| |
Collapse
|
2
|
Sakkos JK, Hernandez-Ortiz S, Osteryoung KW, Ducat DC. Orthogonal Degron System for Controlled Protein Degradation in Cyanobacteria. ACS Synth Biol 2021; 10:1667-1681. [PMID: 34232633 DOI: 10.1021/acssynbio.1c00035] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Synechococcus elongatus PCC 7942 is a model cyanobacterium for study of the circadian clock, photosynthesis, and bioproduction of chemicals, yet nearly 40% of its gene identities and functions remain unknown, in part due to limitations of the existing genetic toolkit. While classical techniques for the study of genes (e.g., deletion or mutagenesis) can yield valuable information about the absence of a gene and its associated protein, there are limits to these approaches, particularly in the study of essential genes. Herein, we developed a tool for inducible degradation of target proteins in S. elongatus by adapting a method using degron tags from the Mesoplasma florum transfer-mRNA (tmRNA) system. We observed that M. florum lon protease can rapidly degrade exogenous and native proteins tagged with the cognate sequence within hours of induction. We used this system to inducibly degrade the essential cell division factor, FtsZ, as well as shell protein components of the carboxysome. Our results have implications for carboxysome biogenesis and the rate of carboxysome turnover during cell growth. Lon protease control of proteins offers an alternative approach for the study of essential proteins and protein dynamics in cyanobacteria.
Collapse
Affiliation(s)
- Jonathan K. Sakkos
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824, United States
| | - Sergio Hernandez-Ortiz
- Department of Microbiology & Molecular Genetics, Michigan State University, East Lansing, Michigan 48824, United States
| | - Katherine W. Osteryoung
- Department of Plant Biology, Michigan State University, East Lansing, Michigan 48824, United States
| | - Daniel C. Ducat
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824, United States
- Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, Michigan 48824, United States
| |
Collapse
|
3
|
Islam MS, Van Nguyen T, Sakamoto W, Takagi S. Phototropin- and photosynthesis-dependent mitochondrial positioning in Arabidopsis thaliana mesophyll cells. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2020; 62:1352-1371. [PMID: 31961050 DOI: 10.1111/jipb.12910] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 01/07/2020] [Indexed: 06/10/2023]
Abstract
Mitochondria are frequently observed in the vicinity of chloroplasts in photosynthesizing cells, and this association is considered necessary for their metabolic interactions. We previously reported that, in leaf palisade cells of Arabidopsis thaliana, mitochondria exhibit blue-light-dependent redistribution together with chloroplasts, which conduct accumulation and avoidance responses under the control of blue-light receptor phototropins. In this study, precise motility analyses by fluorescent microscopy revealed that the individual mitochondria in palisade cells, labeled with green fluorescent protein, exhibit typical stop-and-go movement. When exposed to blue light, the velocity of moving mitochondria increased in 30 min, whereas after 4 h, the frequency of stoppage of mitochondrial movement markedly increased. Using different mutant plants, we concluded that the presence of both phototropin1 and phototropin2 is necessary for the early acceleration of mitochondrial movement. On the contrary, the late enhancement of stoppage of mitochondrial movement occurs only in the presence of phototropin2 and only when intact photosynthesis takes place. A plasma-membrane ghost assay suggested that the stopped mitochondria are firmly adhered to chloroplasts. These results indicate that the physical interaction between mitochondria and chloroplasts is cooperatively mediated by phototropin2- and photosynthesis-dependent signals. The present study might add novel regulatory mechanism for light-dependent plant organelle interactions.
Collapse
Affiliation(s)
- Md Sayeedul Islam
- Department of Biological Sciences, Graduate School of Science, Osaka University, Machikaneyama-cho 1-1, Toyonaka, Osaka, 560-0043, Japan
| | - Toan Van Nguyen
- Department of Biological Sciences, Graduate School of Science, Osaka University, Machikaneyama-cho 1-1, Toyonaka, Osaka, 560-0043, Japan
- Agricultural Genetics Institute, National Key Laboratory for Plant Cell Biotechnology, Pham Van Dong road, Bac Tu Liem district, Ha Noi, Vietnam
| | - Wataru Sakamoto
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Okayama, 710-0046, Japan
| | - Shingo Takagi
- Department of Biological Sciences, Graduate School of Science, Osaka University, Machikaneyama-cho 1-1, Toyonaka, Osaka, 560-0043, Japan
| |
Collapse
|
4
|
Mahbub M, Hemm L, Yang Y, Kaur R, Carmen H, Engl C, Huokko T, Riediger M, Watanabe S, Liu LN, Wilde A, Hess WR, Mullineaux CW. mRNA localization, reaction centre biogenesis and thylakoid membrane targeting in cyanobacteria. NATURE PLANTS 2020; 6:1179-1191. [PMID: 32895528 DOI: 10.1038/s41477-020-00764-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
The thylakoid membranes of cyanobacteria form a complex intracellular membrane system with a distinctive proteome. The sites of biogenesis of thylakoid proteins remain uncertain, as do the signals that direct thylakoid membrane-integral proteins to the thylakoids rather than to the plasma membrane. Here, we address these questions by using fluorescence in situ hybridization to probe the subcellular location of messenger RNA molecules encoding core subunits of the photosystems in two cyanobacterial species. These mRNAs cluster at thylakoid surfaces mainly adjacent to the central cytoplasm and the nucleoid, in contrast to mRNAs encoding proteins with other locations. Ribosome association influences the distribution of the photosynthetic mRNAs on the thylakoid surface, but thylakoid affinity is retained in the absence of ribosome association. However, thylakoid association is disrupted in a mutant lacking two mRNA-binding proteins, which probably play roles in targeting photosynthetic proteins to the thylakoid membrane.
Collapse
Affiliation(s)
- Moontaha Mahbub
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
- Department of Botany, Jagannath University, Dhaka, Bangladesh
| | - Luisa Hemm
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Yuxiao Yang
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Ramanpreet Kaur
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Helder Carmen
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Christoph Engl
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Tuomas Huokko
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
| | | | - Satoru Watanabe
- Department of Bioscience, Tokyo University of Agriculture, Tokyo, Japan
| | - Lu-Ning Liu
- Institute of Integrative Biology, University of Liverpool, Liverpool, UK
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
| | - Annegret Wilde
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Wolfgang R Hess
- Institute of Biology III, University of Freiburg, Freiburg, Germany
| | - Conrad W Mullineaux
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK.
| |
Collapse
|
5
|
Reassimilation of Leaf Internal CO2 Contributes to Isoprene Emission in the Neotropical Species Inga edulis Mart. FORESTS 2019. [DOI: 10.3390/f10060472] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Isoprene (C5H8) is a hydrocarbon gas emitted by many tree species and has been shown to protect photosynthesis under abiotic stress. Under optimal conditions for photosynthesis, ~70%–90% of carbon used for isoprene biosynthesis is produced from recently assimilated atmospheric CO2. While the contribution of alternative carbon sources that increase with leaf temperature and other stresses have been demonstrated, uncertainties remain regarding the biochemical source(s) of isoprene carbon. In this study, we investigated leaf isoprene emissions (Is) from neotropical species Inga edulis Mart. as a function of light and temperature under ambient (450 µmol m−2 s−1) and CO2-free (0 µmol m−2 s−1) atmosphere. Is under CO2-free atmosphere showed light-dependent emission patterns similar to those observed under ambient CO2, but with lower light saturation point. Leaves treated with the photosynthesis inhibitor DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) failed to produce detectable Is in normal light under a CO2-free atmosphere. While strong temperature-dependent Is were observed under CO2-free atmosphere in the light, dark conditions failed to produce detectable Is even at the highest temperatures studied (40 °C). Treatment of leaves with 13C-labeled sodium bicarbonate under CO2-free atmosphere resulted in Is with over 50% containing at least one 13C atom. Is under CO2-free atmosphere and standard conditions of light and leaf temperature represented 19% ± 7% of emissions under ambient CO2. The results show that the reassimilation of leaf internal CO2 contributes to Is in the neotropical species I. edulis. Through the consumption of excess photosynthetic energy, our results support a role of isoprene biosynthesis, together with photorespiration, as a key tolerance mechanism against high temperature and high light in the tropics.
Collapse
|
6
|
Komenda J, Sobotka R. Cyanobacterial high-light-inducible proteins — Protectors of chlorophyll–protein synthesis and assembly. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:288-95. [DOI: 10.1016/j.bbabio.2015.08.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 08/28/2015] [Accepted: 08/30/2015] [Indexed: 12/24/2022]
|
7
|
Light Stress Proteins in Viruses, Cyanobacteria and Photosynthetic Eukaryota. PHOTOSYNTHESIS 2012. [DOI: 10.1007/978-94-007-1579-0_14] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
|
8
|
Li Q, Xing D, Jia L, Wang J. Mechanism study on the origin of delayed fluorescence by an analytic modeling of the electronic reflux for photosynthetic electron transport chain. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2007; 87:183-90. [PMID: 17537642 DOI: 10.1016/j.jphotobiol.2007.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Revised: 04/17/2007] [Accepted: 04/18/2007] [Indexed: 11/20/2022]
Abstract
A mathematical-physical analysis model, which describes individually the electronic reflux of several significant components in the photosynthesis electron transport chain, was firstly developed. The process of electrons flowing back to the oxidized reaction center P(680)(+) was simulated by a series of photochemical reaction equations, resulting in getting the linked differential equations of delayed fluorescence (DF) intensity. MATLAB provided a computationally efficient method to solve these linked equations. Simulations based on this model showed that the decay kinetics of DF accord with double exponential. DF components decaying in the millisecond range (fast phase) are related to the charge recombination of P(680)(+) and Q(A)(-). The components decaying in the seconds range are associated with the recombination of P(680)(+) with Q(B)(2-). The developed model was tested in maize leaves treated with different electron blockers to induce changes in photosynthesis electron transport chain. The experimental results demonstrated that the developed model can accurately determine the regulatory effects of electron blockers on photosynthesis electron transport chain. Therefore, the model presented here could be potentially useful for studying the electron transfer in plant. It also provides an experimental workbench for testing hypotheses as to the underlying mechanism controlling the change for different phases of DF.
Collapse
Affiliation(s)
- Qiang Li
- MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, South China Normal University, Guangzhou 510631, China
| | | | | | | |
Collapse
|
9
|
Promnares K, Komenda J, Bumba L, Nebesarova J, Vacha F, Tichy M. Cyanobacterial small chlorophyll-binding protein ScpD (HliB) is located on the periphery of photosystem II in the vicinity of PsbH and CP47 subunits. J Biol Chem 2006; 281:32705-13. [PMID: 16923804 DOI: 10.1074/jbc.m606360200] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cyanobacteria contain several genes coding for small one-helix proteins called SCPs or HLIPs with significant sequence similarity to chlorophyll a/b-binding proteins. To localize one of these proteins, ScpD, in the cells of the cyanobacterium Synechocystis sp. PCC 6803, we constructed several mutants in which ScpD was expressed as a His-tagged protein (ScpDHis). Using two-dimensional native-SDS electrophoresis of thylakoid membranes or isolated Photosystem II (PSII), we determined that after high-light treatment most of the ScpDHis protein in a cell is associated with PSII. The ScpDHis protein was present in both monomeric and dimeric PSII core complexes and also in the core subcomplex lacking CP43. However, the association with PSII was abolished in the mutant lacking the PSII subunit PsbH. In a PSII mutant lacking cytochrome b(559), which does not accumulate PSII, ScpDHis is associated with CP47. The interaction of ScpDHis with PsbH and CP47 was further confirmed by electron microscopy of PSII labeled with Ni-NTA Nanogold. Single particle image analysis identified the location of the labeled ScpDHis at the periphery of the PSII core complex in the vicinity of the PsbH and CP47. Because of the fact that ScpDHis did not form any large structures bound to PSII and because of its accumulation in PSII subcomplexes containing CP47 and PsbH we suggest that ScpD is involved in a process of PSII assembly/repair during the turnover of pigment-binding proteins, particularly CP47.
Collapse
Affiliation(s)
- Kamoltip Promnares
- Faculty of Biological Sciences, University of South Bohemia, 370 05 Ceske Budejovice, Czech Republic
| | | | | | | | | | | |
Collapse
|
10
|
Kappell AD, Bhaya D, van Waasbergen LG. Negative control of the high light-inducible hliA gene and implications for the activities of the NblS sensor kinase in the cyanobacterium Synechococcus elongatus strain PCC 7942. Arch Microbiol 2006; 186:403-13. [PMID: 16897032 DOI: 10.1007/s00203-006-0154-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Revised: 07/07/2006] [Accepted: 07/14/2006] [Indexed: 11/24/2022]
Abstract
The hliA gene of the cyanobacterium Synechococcus elongatus PCC 7942 is known to be upregulated by high-intensity light through the activity of the NblS sensor kinase. In this work it was found that, within the hliA upstream region, changes to the sequence around -30 to -25 (relative to the transcriptional start site) resulted in elevated hliA expression, implicating this region in negative regulation of the gene. Electrophoretic mobility shift assays performed were consistent with a protein binding this region that acts to keep the gene off in lower light. A reduction in gene dosage of nblS in vivo resulted in enhanced hliA expression, suggesting that negative control of hliA is mediated through NblS. An extended version of the high light regulatory 1 (HLR1) motif (previously described in Synechocystis PCC 6803) was identified within the sequence surrounding -30 to -25 of hliA. The extended HLR1 sequence was found upstream of other NblS-controlled genes from S. elongatus and Synechocystis PCC 6803 and upstream of hli genes from a variety of cyanobacterial and related genomes. These results point to the evolutionary conservation of the HLR1 element and its importance in NblS-mediated signaling and yield new insight into NblS-mediated control of gene expression.
Collapse
Affiliation(s)
- Anthony D Kappell
- Department of Biology, The University of Texas at Arlington, Arlington, TX 76019, USA
| | | | | |
Collapse
|
11
|
Herranen M, Tyystjärvi T, Aro EM. Regulation of photosystem I reaction center genes in Synechocystis sp. strain PCC 6803 during Light acclimation. PLANT & CELL PHYSIOLOGY 2005; 46:1484-93. [PMID: 15979982 DOI: 10.1093/pcp/pci160] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Cyanobacteria acclimate to changes in incident light by adjusting photosystem stoichiometry through regulation of PSI accumulation. To gain a deeper insight into this control mechanism in Synechocystis sp. strain PCC 6803, we studied the expression and regulation of the psaAB operon, encoding the reaction center proteins of PSI, during the initial stage of acclimation to changes in the intensity and quality of light. The psaAB operon was transcribed as a dicistronic transcript, which was processed into smaller, putatively monocistronic psaA and psaB transcript species. Dark treatment of the cells inhibited the psaAB transcription, whereas re-illumination of dark-adapted cells reactivated the transcription slowly in a process requiring de novo protein synthesis. Transfer of cells from white to orange light, favoring excitation of PSII, stimulated the psaAB transcription, whereas far-red light, primarily exciting PSI, down-regulated the transcription of the psaAB operon. These results, together with down-regulation of psaAB transcription upon the addition of electron transport inhibitors under constant white light illumination, suggested that the photosynthetic redox poise affects the psaAB transcription activity in the light. Pulse-labeling experiments demonstrated that light-induced modulations in the translation rate of the PsaA protein closely parallel the transcription rate of the psaAB operon, indicating that transcriptional regulation plays the major role in determining the content of PSI reaction center proteins and, thereby, PSI complexes, during light acclimation. The scantiness of PsaA translation in darkness despite the abundance of psaA transcripts demonstrated that the comprehensive regulation of PSI accumulation also involves regulation at the level of translation.
Collapse
Affiliation(s)
- Mirkka Herranen
- Plant Physiology and Molecular Biology, Department of Biology, University of Turku, FIN-20014 Turku, Finland
| | | | | |
Collapse
|