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Katyal G, Ebanks B, Dowle A, Shephard F, Papetti C, Lucassen M, Chakrabarti L. Quantitative Proteomics and Network Analysis of Differentially Expressed Proteins in Proteomes of Icefish Muscle Mitochondria Compared with Closely Related Red-Blooded Species. Biology 2022; 11:biology11081118. [PMID: 35892974 PMCID: PMC9330239 DOI: 10.3390/biology11081118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 11/29/2022]
Abstract
Simple Summary Antarctic icefish are unusual in that they are the only vertebrates that survive without the protein haemoglobin. One way to try and understand the biological processes that support this anomaly is to record how proteins are regulated in these animals and to compare what we find to closely related Antarctic fish that do still retain haemoglobin. The part of the cell that most clearly utilises oxygen, which is normally transported by haemoglobin, is the mitochondrion. Therefore, we chose to catalogue all the proteins and their relative quantities in the mitochondria (pl.) from two different muscle types in two species of icefish and two species of red-blooded notothenioids. We used an approach called mass spectrometry to reveal relative amounts of the proteins from the muscles of each fish. We present analysis that shows how the connections and relative quantities of proteins differ between these species. Abstract Antarctic icefish are extraordinary in their ability to thrive without haemoglobin. We wanted to understand how the mitochondrial proteome has adapted to the loss of this protein. Metabolic pathways that utilise oxygen are most likely to be rearranged in these species. Here, we have defined the mitochondrial proteomes of both the red and white muscle of two different icefish species (Champsocephalus gunnari and Chionodraco rastrospinosus) and compared these with two related red-blooded Notothenioids (Notothenia rossii, Trematomus bernacchii). Liquid Chromatography-Mass spectrometry (LC-MS/MS) was used to generate and examine the proteomic profiles of the two groups. We recorded a total of 91 differentially expressed proteins in the icefish red muscle mitochondria and 89 in the white muscle mitochondria when compared with the red-blooded related species. The icefish have a relatively higher abundance of proteins involved with Complex V of oxidative phosphorylation, RNA metabolism, and homeostasis, and fewer proteins for striated muscle contraction, haem, iron, creatine, and carbohydrate metabolism. Enrichment analyses showed that many important pathways were different in both red muscle and white muscle, including the citric acid cycle, ribosome machinery and fatty acid degradation. Life in the Antarctic waters poses extra challenges to the organisms that reside within them. Icefish have successfully inhabited this environment and we surmise that species without haemoglobin uniquely maintain their physiology. Our study highlights the mitochondrial protein pathway differences between similar fish species according to their specific tissue oxygenation idiosyncrasies.
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Affiliation(s)
- Gunjan Katyal
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington LE12 5RD, UK; (G.K.); (B.E.); (F.S.)
| | - Brad Ebanks
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington LE12 5RD, UK; (G.K.); (B.E.); (F.S.)
| | - Adam Dowle
- Department of Biology, Bioscience Technology Facility, University of York, York YO10 5DD, UK;
| | - Freya Shephard
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington LE12 5RD, UK; (G.K.); (B.E.); (F.S.)
| | - Chiara Papetti
- Biology Department, University of Padova, Via U. Bassi, 58/b, 35121 Padova, Italy;
| | | | - Lisa Chakrabarti
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington LE12 5RD, UK; (G.K.); (B.E.); (F.S.)
- MRC-Versus Arthritis Centre for Musculoskeletal Ageing Research, Liverpool L7 8TX, UK
- Correspondence:
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Abstract
Background: Brain cholesterol levels are tightly regulated but increasing evidence indicates that cholesterol metabolism may drive Alzheimer’s disease (AD)-associated pathological changes. Recent advances in understanding of mitochondrial dysfunction in AD brain have presented a vital role played by mitochondria in oxysterol biosynthesis and their involvement in pathophysiology. Oxysterol accumulation in brain is controlled by various enzymatic pathways including sulfation. While research into oxysterol is under the areas of active investigation, there is less evidence for oxysterol sulfate levels in human brain. Objective: This study investigates the hypothesis that AD brain oxysterol detoxification via sulfation is impaired in later stages of disease resulting in oxysterol accumulation. Methods: Lipids were extracted from postmortem frozen brain tissue and cerebrospinal (CSF) from late- (Braak stage III-IV) and early- (Braak stage I-II) stage AD patients. Samples were spiked with internal standards prior to lipid extraction. Oxysterols were enriched with a two-step solid phase extraction using a polymeric SPE column and further separation was achieved by LC-MS/MS. Results: Oxysterols, 26-hydroxycholesterol (26-OHC), 25-hydroxycholesterol (25-OHC), and 7-oxycholesterol levels were higher in brain tissue and mitochondria extracted from late-stage AD brain tissue except for 24S-hydroxycholesterol, which was decreased in late AD. However, oxysterol sulfates are significantly lower in the AD frontal cortex. Oxysterols, 25-OHC, and 7-oxocholesterol was higher is CSF but 26-OHC and oxysterol sulfate levels were not changed. Conclusion: Our results show oxysterol metabolism is altered in AD brain mitochondria, favoring synthesis of 26-OHC, 25-OHC, and 7-oxocholesterol, and this may influence brain mitochondrial function and acceleration of the disease.
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Affiliation(s)
- Irundika H.K. Dias
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham, UK
| | - Hala Shokr
- Manchester Pharmacy School, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Freya Shephard
- Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
| | - Lisa Chakrabarti
- Faculty of Medicine and Health Sciences, University of Nottingham, Nottingham, UK
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Ingram TL, Shephard F, Sarmad S, Ortori CA, Barrett DA, Chakrabarti L. Sex specific inflammatory profiles of cerebellar mitochondria are attenuated in Parkinson's disease. Aging (Albany NY) 2020; 12:17713-17737. [PMID: 32855358 PMCID: PMC7521528 DOI: 10.18632/aging.103937] [Citation(s) in RCA: 4] [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: 06/04/2020] [Accepted: 08/01/2020] [Indexed: 01/24/2023]
Abstract
Response to inflammation is a key determinant in many diseases and their outcomes. Diseases that commonly affect older people are frequently associated with altered inflammatory processes. Neuroinflammation has been described in Parkinson's disease (PD) brain. PD is characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta and at the sub-cellular level, mitochondrial dysfunction is a key feature. However, there is evidence that a different region of the brain, the cerebellum, is involved in the pathophysiology of PD. We report relative levels of 40 pro- and anti-inflammatory cytokines measured in PD and control cerebellar mitochondria. These data were obtained by screening cytokine antibody arrays. In parallel, we present concentrations of 29 oxylipins and 4 endocannabinoids measured in mitochondrial fractions isolated from post-mortem PD cerebellum with age and sex matched controls. Our oxylipin and endocannabinoid data were acquired via quantitation by LC-ESI-MS/MS. The separate sample sets both show there are clearly different inflammatory profiles between the sexes in control samples. Sex specific profiles were not maintained in cerebellar mitochondria isolated from PD brains.
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Affiliation(s)
- Thomas L. Ingram
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK
| | - Freya Shephard
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK
| | - Sarir Sarmad
- Centre for Analytical Bioscience, Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, UK
| | - Catherine A. Ortori
- Centre for Analytical Bioscience, Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, UK
| | - David A. Barrett
- Centre for Analytical Bioscience, Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, UK
| | - Lisa Chakrabarti
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK
- MRC Versus Arthritis Centre for Musculoskeletal Ageing Research, UK
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Pollard A, Shephard F, Freed J, Liddell S, Chakrabarti L. Mitochondrial proteomic profiling reveals increased carbonic anhydrase II in aging and neurodegeneration. Aging (Albany NY) 2017; 8:2425-2436. [PMID: 27743511 PMCID: PMC5115898 DOI: 10.18632/aging.101064] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [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: 06/16/2016] [Accepted: 09/25/2016] [Indexed: 01/26/2023]
Abstract
Carbonic anhydrase inhibitors are used to treat glaucoma and cancers. Carbonic anhydrases perform a crucial role in the conversion of carbon dioxide and water into bicarbonate and protons. However, there is little information about carbonic anhydrase isoforms during the process of ageing. Mitochondrial dysfunction is implicit in ageing brain and muscle. We have interrogated isolated mitochondrial fractions from young adult and middle aged mouse brain and skeletal muscle. We find an increase of tissue specific carbonic anhydrases in mitochondria from middle-aged brain and skeletal muscle. Mitochondrial carbonic anhydrase II was measured in the Purkinje cell degeneration (pcd5J) mouse model. In pcd5J we find mitochondrial carbonic anhydrase II is also elevated in brain from young adults undergoing a process of neurodegeneration. We show C.elegans exposed to carbonic anhydrase II have a dose related shorter lifespan suggesting that high CAII levels are in themselves life limiting. We show for the first time that the mitochondrial content of brain and skeletal tissue are exposed to significantly higher levels of active carbonic anhydrases as early as in middle-age. Carbonic anhydrases associated with mitochondria could be targeted to specifically modulate age related impairments and disease.
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Affiliation(s)
- Amelia Pollard
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, LE12 5RD, UK
| | - Freya Shephard
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, LE12 5RD, UK
| | - James Freed
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, LE12 5RD, UK
| | - Susan Liddell
- School of Biosciences, University of Nottingham, Sutton Bonington, LE12 5RD, UK
| | - Lisa Chakrabarti
- School of Biosciences, University of Nottingham, Sutton Bonington, LE12 5RD, UK
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Shephard F, Greville-Heygate O, Liddell S, Emes R, Chakrabarti L. Analysis of Mitochondrial haemoglobin in Parkinson's disease brain. Mitochondrion 2016; 29:45-52. [PMID: 27181046 PMCID: PMC4940210 DOI: 10.1016/j.mito.2016.05.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 04/29/2016] [Accepted: 05/03/2016] [Indexed: 01/14/2023]
Abstract
Mitochondrial dysfunction is an early feature of neurodegeneration. We have shown there are mitochondrial haemoglobin changes with age and neurodegeneration. We hypothesised that altered physiological processes are associated with recruitment and localisation of haemoglobin to these organelles. To confirm a dynamic localisation of haemoglobin we exposed Drosophila melanogaster to cyclical hypoxia with recovery. With a single cycle of hypoxia and recovery we found a relative accumulation of haemoglobin in the mitochondria compared with the cytosol. An additional cycle of hypoxia and recovery led to a significant increase of mitochondrial haemoglobin (p<0.05). We quantified ratios of human mitochondrial haemoglobin in 30 Parkinson's and matched control human post-mortem brains. Relative mitochondrial/cytosolic quantities of haemoglobin were obtained for the cortical region, substantia nigra and cerebellum. In age matched post-mortem brain mitochondrial haemoglobin ratios change, decreasing with disease duration in female cerebellum samples (n=7). The change is less discernible in male cerebellum (n=18). In cerebellar mitochondria, haemoglobin localisation in males with long disease duration shifts from the intermembrane space to the outer membrane of the organelle. These new data illustrate dynamic localisation of mitochondrial haemoglobin within the cell. Mitochondrial haemoglobin should be considered in the context of gender differences characterised in Parkinson's disease. It has been postulated that cerebellar circuitry may be activated to play a protective role in individuals with Parkinson's. The changing localisation of intracellular haemoglobin in response to hypoxia presents a novel pathway to delineate the role of the cerebellum in Parkinson's disease.
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Affiliation(s)
- Freya Shephard
- University of Nottingham, Faculty of Medicine, SVMS, Sutton Bonington Campus, LE12 5RD, England, UK
| | - Oliver Greville-Heygate
- University of Nottingham, Faculty of Medicine, SVMS, Sutton Bonington Campus, LE12 5RD, England, UK
| | - Susan Liddell
- Division of Animal Sciences, School of Biosciences, Sutton Bonington Campus, LE12 5RD, England, UK
| | - Richard Emes
- University of Nottingham, Faculty of Medicine, SVMS, Sutton Bonington Campus, LE12 5RD, England, UK
| | - Lisa Chakrabarti
- University of Nottingham, Faculty of Medicine, SVMS, Sutton Bonington Campus, LE12 5RD, England, UK.
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Gaffney CJ, Shephard F, Chu J, Baillie DL, Rose A, Constantin-Teodosiu D, Greenhaff PL, Szewczyk NJ. Degenerin channel activation causes caspase-mediated protein degradation and mitochondrial dysfunction in adult C. elegans muscle. J Cachexia Sarcopenia Muscle 2016; 7:181-92. [PMID: 27493871 PMCID: PMC4864282 DOI: 10.1002/jcsm.12040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 03/17/2015] [Accepted: 04/09/2015] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Declines in skeletal muscle structure and function are found in various clinical populations, but the intramuscular proteolytic pathways that govern declines in these individuals remain relatively poorly understood. The nematode Caenorhabditis elegans has been developed into a model for identifying and understanding these pathways. Recently, it was reported that UNC-105/degenerin channel activation produced muscle protein degradation via an unknown mechanism. METHODS Generation of transgenic and double mutant C. elegans, RNAi, and drug treatments were utilized to assess molecular events governing protein degradation. Western blots were used to measure protein content. Cationic dyes and adenosine triphosphate (ATP) production assays were utilized to measure mitochondrial function. RESULTS unc-105 gain-of-function mutants display aberrant muscle protein degradation and a movement defect; both are reduced in intragenic revertants and in let-2 mutants that gate the hyperactive UNC-105 channel. Degradation is not suppressed by interventions suppressing proteasome-mediated, autophagy-mediated, or calpain-mediated degradation nor by suppressors of degenerin-induced neurodegeneration. Protein degradation, but not the movement defect, is decreased by treatment with caspase inhibitors or RNAi against ced-3 or ced-4. Adult unc-105 muscles display a time-dependent fragmentation of the mitochondrial reticulum that is associated with impaired mitochondrial membrane potential and that correlates with decreased rates of maximal ATP production. Reduced levels of CED-4, which is sufficient to activate CED-3 in vitro, are observed in unc-105 mitochondrial isolations. CONCLUSIONS Constitutive cationic influx into muscle appears to cause caspase degradation of cytosolic proteins as the result of mitochondrial dysfunction, which may be relevant to ageing and sarcopenia.
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Affiliation(s)
- Christopher J Gaffney
- MRC/ARUK Centre for Musculoskeletal Ageing Research, Faculty of Medicine and Health Sciences University of Nottingham Nottingham NG7 2UH UK
| | - Freya Shephard
- MRC/ARUK Centre for Musculoskeletal Ageing Research, Faculty of Medicine and Health Sciences University of Nottingham Nottingham NG7 2UH UK
| | - Jeff Chu
- Department of Molecular Biology and Biochemistry Simon Fraser University Burnaby BCV5A 1S6 Canada; Department of Medical Genetics University of British Columbia Vancouver BCV6T 1Z4 Canada
| | - David L Baillie
- Department of Molecular Biology and Biochemistry Simon Fraser University Burnaby BC V5A 1S6 Canada
| | - Ann Rose
- Department of Medical Genetics University of British Columbia Vancouver BC V6T 1Z4 Canada
| | - Dumitru Constantin-Teodosiu
- MRC/ARUK Centre for Musculoskeletal Ageing Research, Faculty of Medicine and Health Sciences University of Nottingham Nottingham NG7 2UH UK
| | - Paul L Greenhaff
- MRC/ARUK Centre for Musculoskeletal Ageing Research, Faculty of Medicine and Health Sciences University of Nottingham Nottingham NG7 2UH UK
| | - Nathaniel J Szewczyk
- MRC/ARUK Centre for Musculoskeletal Ageing Research, Faculty of Medicine and Health Sciences University of Nottingham Nottingham NG7 2UH UK
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Etheridge T, Rahman M, Gaffney CJ, Shaw D, Shephard F, Magudia J, Solomon DE, Milne T, Blawzdziewicz J, Constantin-Teodosiu D, Greenhaff PL, Vanapalli SA, Szewczyk NJ. The integrin-adhesome is required to maintain muscle structure, mitochondrial ATP production, and movement forces in Caenorhabditis elegans. FASEB J 2014; 29:1235-46. [PMID: 25491313 PMCID: PMC4396603 DOI: 10.1096/fj.14-259119] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 11/11/2014] [Indexed: 01/19/2023]
Abstract
The integrin-adhesome network, which contains >150 proteins, is mechano-transducing and located at discreet positions along the cell-cell and cell-extracellular matrix interface. A small subset of the integrin-adhesome is known to maintain normal muscle morphology. However, the importance of the entire adhesome for muscle structure and function is unknown. We used RNA interference to knock down 113 putative Caenorhabditis elegans homologs constituting most of the mammalian adhesome and 48 proteins known to localize to attachment sites in C. elegans muscle. In both cases, we found >90% of components were required for normal muscle mitochondrial structure and/or proteostasis vs. empty vector controls. Approximately half of these, mainly proteins that physically interact with each other, were also required for normal sarcomere and/or adhesome structure. Next we confirmed that the dystrophy observed in adhesome mutants associates with impaired maximal mitochondrial ATP production (P < 0.01), as well as reduced probability distribution of muscle movement forces compared with wild-type animals. Our results show that the integrin-adhesome network as a whole is required for maintaining both muscle structure and function and extend the current understanding of the full complexities of the functional adhesome in vivo.—Etheridge, T., Rahman, M., Gaffney, C. J., Shaw, D., Shephard, F., Magudia, J., Solomon, D. E., Milne, T., Blawzdziewicz, J., Constantin-Teodosiu, D., Greenhaff, P. L., Vanapalli, S. A., Szewczyk, N. J. The integrin-adhesome is required to maintain muscle structure, mitochondrial ATP production, and movement forces in Caenorhabditis elegans.
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Affiliation(s)
- Timothy Etheridge
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Mizanur Rahman
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Christopher J Gaffney
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Debra Shaw
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Freya Shephard
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Jignesh Magudia
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Deepak E Solomon
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Thomas Milne
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Jerzy Blawzdziewicz
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Dumitru Constantin-Teodosiu
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Paul L Greenhaff
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Siva A Vanapalli
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
| | - Nathaniel J Szewczyk
- *Department of Sport and Health Science, College of Life and Environmental Sciences, and College of Engineering, Mathematics and Physical Science, University of Exeter, Exeter, United Kingdom; Departments of Chemical Engineering and Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA; Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, Schools of Life Sciences and Medicine, University of Nottingham, Nottingham, United Kingdom; and School of Veterinary Medicine and Science, University of Nottingham, Leicestershire, United Kingdom
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Muñoz-Lobato F, Rodríguez-Palero MJ, Naranjo-Galindo FJ, Shephard F, Gaffney CJ, Szewczyk NJ, Hamamichi S, Caldwell KA, Caldwell GA, Link CD, Miranda-Vizuete A. Protective role of DNJ-27/ERdj5 in Caenorhabditis elegans models of human neurodegenerative diseases. Antioxid Redox Signal 2014; 20:217-35. [PMID: 23641861 PMCID: PMC3887457 DOI: 10.1089/ars.2012.5051] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
AIMS Cells have developed quality control systems for protection against proteotoxicity. Misfolded and aggregation-prone proteins, which are behind the initiation and progression of many neurodegenerative diseases (ND), are known to challenge the proteostasis network of the cells. We aimed to explore the role of DNJ-27/ERdj5, an endoplasmic reticulum (ER)-resident thioredoxin protein required as a disulfide reductase for the degradation of misfolded proteins, in well-established Caenorhabditis elegans models of Alzheimer, Parkinson and Huntington diseases. RESULTS We demonstrate that DNJ-27 is an ER luminal protein and that its expression is induced upon ER stress via IRE-1/XBP-1. When dnj-27 expression is downregulated by RNA interference we find an increase in the aggregation and associated pathological phenotypes (paralysis and motility impairment) caused by human β-amyloid peptide (Aβ), α-synuclein (α-syn) and polyglutamine (polyQ) proteins. In turn, DNJ-27 overexpression ameliorates these deleterious phenotypes. Surprisingly, despite being an ER-resident protein, we show that dnj-27 downregulation alters cytoplasmic protein homeostasis and causes mitochondrial fragmentation. We further demonstrate that DNJ-27 overexpression substantially protects against the mitochondrial fragmentation caused by human Aβ and α-syn peptides in these worm models. INNOVATION We identify C. elegans dnj-27 as a novel protective gene for the toxicity associated with the expression of human Aβ, α-syn and polyQ proteins, implying a protective role of ERdj5 in Alzheimer, Parkinson and Huntington diseases. CONCLUSION Our data support a scenario where the levels of DNJ-27/ERdj5 in the ER impact cytoplasmic protein homeostasis and the integrity of the mitochondrial network which might underlie its protective effects in models of proteotoxicity associated to human ND.
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Affiliation(s)
- Fernando Muñoz-Lobato
- 1 Centro Andaluz de Biología del Desarrollo (CABD-CSIC), Depto. de Fisiología, Anatomía y Biología Celular, Universidad Pablo de Olavide , Sevilla, Spain
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Shephard F, Greville-Heygate O, Marsh O, Anderson S, Chakrabarti L. A mitochondrial location for haemoglobins--dynamic distribution in ageing and Parkinson's disease. Mitochondrion 2013; 14:64-72. [PMID: 24333691 PMCID: PMC3969298 DOI: 10.1016/j.mito.2013.12.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [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: 07/26/2013] [Revised: 11/08/2013] [Accepted: 12/02/2013] [Indexed: 11/12/2022]
Abstract
Haemoglobins are iron-containing proteins that transport oxygen in the blood of most vertebrates. The mitochondrion is the cellular organelle which consumes oxygen in order to synthesise ATP. Mitochondrial dysfunction is implicated in neurodegeneration and ageing. We find that α and β haemoglobin (Hba and Hbb) proteins are altered in their distribution in mitochondrial fractions from degenerating brain. We demonstrate that both Hba and Hbb are co-localised with the mitochondrion in mammalian brain. The precise localisation of the Hbs is within the inner membrane space and associated with inner mitochondrial membrane. Relative mitochondrial to cytoplasmic ratios of Hba and Hbb show changing distributions of these proteins during the process of neurodegeneration in the pcd5j mouse brain. A significant difference in mitochondrial Hba and Hbb content in the mitochondrial fraction is seen at 31 days after birth, this corresponds to a stage when dynamic neuronal loss is measured to be greatest in the Purkinje Cell Degeneration mouse. We also report changes in mitochondrial Hba and Hbb levels in ageing brain and muscle. Significant differences in mitochondrial Hba and Hbb can be seen when comparing aged brain to muscle, suggesting tissue specific functions of these proteins in the mitochondrion. In muscle there are significant differences between Hba levels in old and young mitochondria. To understand whether the changes detected in mitochondrial Hbs are of clinical significance, we examined Parkinson's disease brain, immunohistochemistry studies suggest that cell bodies in the substantia nigra accumulate mitochondrial Hb. However, western blotting of mitochondrial fractions from PD and control brains indicates significantly less Hb in PD brain mitochondria. One explanation could be a specific loss of cells containing mitochondria loaded with Hb proteins. Our study opens the door to an examination of the role of Hb function, within the context of the mitochondrion—in health and disease. Both Hba and Hbb are co-localised with the mitochondrion in mammalian brain. Hbs are located in the inter membrane space and inner mitochondrial membrane. α and β haemoglobin protein distribution changes with age in brain mitochondria. Mitochondrial fractions from PD brains contain significantly less Hb than controls.
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Affiliation(s)
- Freya Shephard
- School of Veterinary Medicine and Science, Faculty of Medicine and Health Sciences, University of Nottingham, LE12 5RD, United Kingdom
| | - Oliver Greville-Heygate
- School of Veterinary Medicine and Science, Faculty of Medicine and Health Sciences, University of Nottingham, LE12 5RD, United Kingdom
| | - Oliver Marsh
- School of Veterinary Medicine and Science, Faculty of Medicine and Health Sciences, University of Nottingham, LE12 5RD, United Kingdom
| | - Susan Anderson
- Graduate Entry Medicine, University of Nottingham, DE22 3DT, United Kingdom
| | - Lisa Chakrabarti
- School of Veterinary Medicine and Science, Faculty of Medicine and Health Sciences, University of Nottingham, LE12 5RD, United Kingdom.
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10
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Warren P, Golden A, Hanover J, Love D, Shephard F, Szewczyk NJ. Evaluation of the Fluids Mixing Enclosure System for Life Science Experiments During a Commercial Caenorhabditis elegans Spaceflight Experiment. Adv Space Res 2013; 51:2241-2250. [PMID: 23794777 PMCID: PMC3684985 DOI: 10.1016/j.asr.2013.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The Student Spaceflight Experiments Program (SSEP) is a United States national science, technology, engineering, and mathematics initiative that aims to increase student interest in science by offering opportunities to perform spaceflight experiments. The experiment detailed here was selected and flown aboard the third SSEP mission and the first SSEP mission to the International Space Station (ISS). Caenorhabditis elegans is a small, transparent, self-fertilizing hermaphroditic roundworm that is commonly used in biological experiments both on Earth and in Low Earth Orbit. Past experiments have found decreased expression of mRNA for several genes whose expression can be controlled by the FOXO transcription factor DAF-16. We flew a daf-16 mutant and control worms to determine if the effects of spaceflight on C. elegans are mediated by DAF-16. The experiment used a Type Two Fluids Mixing Enclosure (FME), developed by Nanoracks LLC, and was delivered to the ISS aboard the SpaceX Dragon and returned aboard the Russian Soyuz. The short time interval between experiment selection and the flight rendered preflight experiment verification tests impossible. In addition, published research regarding the viability of the FME in life science experiments was not available. The experiment was therefore structured in such a way as to gather the needed data. Here we report that C. elegans can survive relatively short storage and activation in the FME but cannot produce viable populations for post-flight analysis on extended missions. The FME appears to support short-duration life science experiments, potentially on supply or crew exchange missions, but not on longer ISS expeditions. Additionally, the flown FME was not properly activated, reportedly due to a flaw in training procedures. We suggest that a modified transparent FME could prevent similar failures in future flight experiments.
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Affiliation(s)
- Paul Warren
- Henry E. Lackey High School, 3000 Chicamuxen Road, Indian Head, MD 20640, USA
| | - Andy Golden
- Laboratories of Biochemistry and Genetics and of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - John Hanover
- Laboratories of Biochemistry and Genetics and of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Dona Love
- Laboratories of Biochemistry and Genetics and of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Freya Shephard
- Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham, Royal Derby Hospital, Derby, DE22 3DT, UK
| | - Nathaniel J. Szewczyk
- Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Nottingham, Royal Derby Hospital, Derby, DE22 3DT, UK
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11
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Criswell J, Potter K, Shephard F, Beale MH, Peters RJ. A single residue change leads to a hydroxylated product from the class II diterpene cyclization catalyzed by abietadiene synthase. Org Lett 2012; 14:5828-31. [PMID: 23167845 DOI: 10.1021/ol3026022] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Class II diterpene cyclases catalyze bicyclization of geranylgeranyl diphosphate. While this reaction typically is terminated via methyl deprotonation to yield copalyl diphosphate, in rare cases hydroxylated bicycles are produced instead. Abietadiene synthase is a bifunctional diterpene cyclase that usually produces a copalyl diphosphate intermediate. Here it is shown that substitution of aspartate for a conserved histidine in the class II active site of abietadiene synthase leads to selective production of 8α-hydroxy-CPP instead, demonstrating striking plasticity.
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Affiliation(s)
- Jared Criswell
- Department of Biochemistry, Biophysics, & Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
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12
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Lehmann S, Shephard F, Jacobson LA, Szewczyk NJ. Integrated control of protein degradation in C. elegans muscle. Worm 2012; 1:141-50. [PMID: 23457662 PMCID: PMC3583358 DOI: 10.4161/worm.20465] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 04/14/2012] [Accepted: 04/23/2012] [Indexed: 12/26/2022]
Abstract
Protein degradation is a fundamental cellular process, the genomic control of which is incompletely understood. The advent of transgene-coded reporter proteins has enabled the development of C. elegans into a model for studying this problem. The regulation of muscle protein degradation is surprisingly complex, integrating multiple signals from hypodermis, intestine, neurons and muscle itself. Within the muscle, degradation is executed by separately regulated autophagy-lysosomal, ubiquitin-proteasome and calpain-mediated systems. The signal-transduction mechanisms, in some instances, involve modules previously identified for their roles in developmental processes, repurposed in terminally differentiated muscle to regulate the activities of pre-formed proteins. Here we review the genes, and mechanisms, which appear to coordinately control protein degradation within C. elegans muscle. We also consider these mechanisms in the context of development, physiology, pathophysiology and disease models.
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Affiliation(s)
- Susann Lehmann
- Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research; University of Nottingham; Royal Derby Hospital; Derby, UK
| | - Freya Shephard
- Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research; University of Nottingham; Royal Derby Hospital; Derby, UK
| | - Lewis A. Jacobson
- Department of Biological Sciences; University of Pittsburgh; Pittsburgh, PA USA
| | - Nathaniel J. Szewczyk
- Medical Research Council/Arthritis Research UK Centre for Musculoskeletal Ageing Research; University of Nottingham; Royal Derby Hospital; Derby, UK
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13
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Zhang X, Pino GM, Shephard F, Kiss-Toth E, Qwarnstrom EE. Distinct control of MyD88 adapter-dependent and Akt kinase-regulated responses by the interleukin (IL)-1RI co-receptor, TILRR. J Biol Chem 2012; 287:12348-52. [PMID: 22262840 DOI: 10.1074/jbc.c111.321711] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Inflammatory responses are controlled through members of the interleukin-1 receptor (IL-1R)/Toll-like receptor superfamily. Our earlier work demonstrates that the IL-1 receptor type 1 (IL-1RI) co-receptor, Toll-like and IL-1 receptor regulator (TILRR), amplifies IL-1 activation of NF-κB and inflammatory genes. Here we show that TILRR similarly promotes IL-1-induced anti-apoptotic signals and reduces caspase-3 activity. Further, the TILRR-induced effects on cell survival and inflammatory responses are controlled through distinct parts of the IL-1RI regulatory Toll IL-1 receptor (TIR) domain. Alanine-scanning mutagenesis identified a functional TILRR mutant (R425A), which blocked increases in cell survival and upstream activation of Akt but had no effect on amplification of MyD88-dependent inflammatory responses. A second mutant (D448A) blocked TILRR potentiation of MyD88-dependent signals and inflammatory activation but had no impact on cell survival. Secondary structure predictions suggested that the mutations induce distinct alterations in the α-helical structure of the TILRR core protein. The results indicate a role for TILRR in selective amplification of NF-κB responses through IL-1RI and suggest that the specificity is determined by changes in receptor conformation and adapter protein recruitment.
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Affiliation(s)
- Xiao Zhang
- Cell Biology Group, University of Sheffield, Sheffield S10 2RX, United Kingdom
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14
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Etheridge T, Oczypok EA, Lehmann S, Fields BD, Shephard F, Jacobson LA, Szewczyk NJ. Calpains mediate integrin attachment complex maintenance of adult muscle in Caenorhabditis elegans. PLoS Genet 2012; 8:e1002471. [PMID: 22253611 PMCID: PMC3257289 DOI: 10.1371/journal.pgen.1002471] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 11/23/2011] [Indexed: 11/23/2022] Open
Abstract
Two components of integrin containing attachment complexes, UNC-97/PINCH and UNC-112/MIG-2/Kindlin-2, were recently identified as negative regulators of muscle protein degradation and as having decreased mRNA levels in response to spaceflight. Integrin complexes transmit force between the inside and outside of muscle cells and signal changes in muscle size in response to force and, perhaps, disuse. We therefore investigated the effects of acute decreases in expression of the genes encoding these multi-protein complexes. We find that in fully developed adult Caenorhabditis elegans muscle, RNAi against genes encoding core, and peripheral, members of these complexes induces protein degradation, myofibrillar and mitochondrial dystrophies, and a movement defect. Genetic disruption of Z-line– or M-line–specific complex members is sufficient to induce these defects. We confirmed that defects occur in temperature-sensitive mutants for two of the genes: unc-52, which encodes the extra-cellular ligand Perlecan, and unc-112, which encodes the intracellular component Kindlin-2. These results demonstrate that integrin containing attachment complexes, as a whole, are required for proper maintenance of adult muscle. These defects, and collapse of arrayed attachment complexes into ball like structures, are blocked when DIM-1 levels are reduced. Degradation is also blocked by RNAi or drugs targeting calpains, implying that disruption of integrin containing complexes results in calpain activation. In wild-type animals, either during development or in adults, RNAi against calpain genes results in integrin muscle attachment disruptions and consequent sub-cellular defects. These results demonstrate that calpains are required for proper assembly and maintenance of integrin attachment complexes. Taken together our data provide in vivo evidence that a calpain-based molecular repair mechanism exists for dealing with attachment complex disruption in adult muscle. Since C. elegans lacks satellite cells, this mechanism is intrinsic to the muscles and raises the question if such a mechanism also exists in higher metazoans. Muscle is a dynamic tissue that grows in response to use and nutrition and shrinks in response to lack of use, poor nutrition, or disease. Loss of muscle mass is an important public health problem, but we understand little of the genes that regulate muscle shrinkage. We have found that, in adult worm muscle, attachment to the basement membrane is continuously required to prevent catastrophic sub-cellular defects that result in impaired ability of muscle to function. We have also identified a group of proteases that are activated when the attachment fails to be properly maintained. Conversely, when these proteases are lacking in adult muscle, the muscles fail to maintain attachment to the basement membrane. Thus, we have discovered a group of proteases that appear to act to maintain attachment to the basement membrane and therefore to maintain muscle itself. Because these worms lack satellite cells, this maintenance system is intrinsic to muscle, thus raising the question whether a similar or identical system also works in humans.
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Affiliation(s)
- Timothy Etheridge
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| | - Elizabeth A. Oczypok
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Susann Lehmann
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| | - Brandon D. Fields
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Freya Shephard
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| | - Lewis A. Jacobson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Nathaniel J. Szewczyk
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
- * E-mail:
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15
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Shephard F, Adenle AA, Jacobson LA, Szewczyk NJ. Identification and functional clustering of genes regulating muscle protein degradation from amongst the known C. elegans muscle mutants. PLoS One 2011; 6:e24686. [PMID: 21980350 PMCID: PMC3181249 DOI: 10.1371/journal.pone.0024686] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 08/15/2011] [Indexed: 01/08/2023] Open
Abstract
Loss of muscle mass via protein degradation is an important clinical problem but we know little of how muscle protein degradation is regulated genetically. To gain insight our labs developed C. elegans into a model for understanding the regulation of muscle protein degradation. Past studies uncovered novel functional roles for genes affecting muscle and/or involved in signalling in other cells or tissues. Here we examine most of the genes previously identified as the sites of mutations affecting muscle for novel roles in regulating degradation. We evaluate genomic (RNAi knockdown) approaches and combine them with our established genetic (mutant) and pharmacologic (drugs) approaches to examine these 159 genes. We find that RNAi usually recapitulates both organismal and sub-cellular mutant phenotypes but RNAi, unlike mutants, can frequently be used acutely to study gene function solely in differentiated muscle. In the majority of cases where RNAi does not produce organismal level phenotypes, sub-cellular defects can be detected; disrupted proteostasis is most commonly observed. We identify 48 genes in which mutation or RNAi knockdown causes excessive protein degradation; myofibrillar and/or mitochondrial morphologies are also disrupted in 19 of these 48 cases. These 48 genes appear to act via at least three sub-networks to control bulk degradation of protein in muscle cytosol. Attachment to the extracellular matrix regulates degradation via unidentified proteases and affects myofibrillar and mitochondrial morphology. Growth factor imbalance and calcium overload promote lysosome based degradation whereas calcium deficit promotes proteasome based degradation, in both cases myofibrillar and mitochondrial morphologies are largely unaffected. Our results provide a framework for effectively using RNAi to identify and functionally cluster novel regulators of degradation. This clustering allows prioritization of candidate genes/pathways for future mechanistic studies.
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Affiliation(s)
- Freya Shephard
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| | - Ademola A. Adenle
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
| | - Lewis A. Jacobson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Nathaniel J. Szewczyk
- School of Graduate Entry Medicine and Health, University of Nottingham, Royal Derby Hospital, Derby, United Kingdom
- * E-mail:
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16
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Zhang X, Shephard F, Kim HB, Palmer IR, McHarg S, Fowler GJ, O'Neill LA, Kiss-Toth E, Qwarnstrom EE. TILRR, a novel IL-1RI co-receptor, potentiates MyD88 recruitment to control Ras-dependent amplification of NF-κB. J Biol Chem 2010. [DOI: 10.1074/jbc.a109.073429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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17
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Zhang X, Shephard F, Kim HB, Palmer IR, McHarg S, Fowler GJS, O'Neill LAJ, Kiss-Toth E, Qwarnstrom EE. TILRR, a novel IL-1RI co-receptor, potentiates MyD88 recruitment to control Ras-dependent amplification of NF-kappaB. J Biol Chem 2009; 285:7222-32. [PMID: 19940113 PMCID: PMC2844171 DOI: 10.1074/jbc.m109.073429] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Host defense against infection is induced by Toll-like and interleukin (IL)-1 receptors, and controlled by the transcription factor NF-κB. Our earlier studies have shown that IL-1 activation impacts cytoskeletal structure and that IL-1 receptor (IL-1RI) function is substrate-dependent. Here we identify a novel regulatory component, TILRR, which amplifies activation of IL-1RI and coordinates IL-1-induced control with mechanotransduction. We show that TILRR is a highly conserved and widely expressed enhancer of IL-1-regulated inflammatory responses and, further, that it is a membrane-bound glycosylated protein with sequence homology to members of the FRAS-1 family. We demonstrate that TILRR is recruited to the IL-1 receptor complex and magnifies signal amplification by increasing receptor expression and ligand binding. In addition, we show that the consequent potentiation of NF-κB is controlled through IL-1RI-associated signaling components in coordination with activation of the Ras GTPase. Using mutagenesis, we demonstrate that TILRR function is dependent on association with its signaling partner and, further, that formation of the TILRR-containing IL-1RI complex imparts enhanced association of the MyD88 adapter during ligand-induced activation of NF-κB. We conclude that TILRR is an IL-1RI co-receptor, which associates with the signaling receptor complex to enhance recruitment of MyD88 and control Ras-dependent amplification of NF-κB and inflammatory responses.
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Affiliation(s)
- Xiao Zhang
- Units of Cell Biology, University of Sheffield, Sheffield S102RX, United Kingdom
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18
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Walters RG, Shephard F, Rogers JJM, Rolfe SA, Horton P. Identification of mutants of Arabidopsis defective in acclimation of photosynthesis to the light environment. Plant Physiol 2003; 131:472-81. [PMID: 12586872 PMCID: PMC166824 DOI: 10.1104/pp.015479] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2002] [Revised: 10/23/2002] [Accepted: 10/23/2002] [Indexed: 05/20/2023]
Abstract
In common with many other higher plant species, Arabidopsis undergoes photosynthetic acclimation, altering the composition of the photosynthetic apparatus in response to fluctuations in its growth environment. The changes in photosynthetic function that result from acclimation can be detected in a noninvasive manner by monitoring chlorophyll (Chl) fluorescence. This technique has been used to develop a screen that enables the rapid identification of plants defective at ACCLIMATION OF PHOTOSYNTHESIS TO THE ENVIRONMENT (APE) loci. The application of this screen to a population of T-DNA-transformed Arabidopsis has successfully led to the identification of a number of mutant lines with altered Chl fluorescence characteristics. Analysis of photosynthesis and pigment composition in leaves from three such mutants showed that they had altered acclimation responses to the growth light environment, each having a distinct acclimation-defective phenotype, demonstrating that screening for mutants using Chl fluorescence is a viable strategy for the investigation of acclimation. Sequencing of the genomic DNA flanking the T-DNA elements showed that in the ape1 mutant, a gene was disrupted that encodes a protein of unknown function but that appears to be specific to photosynthetic organisms, whereas the ape2 mutant carries an insertion in the region of the TPT gene encoding the chloroplast inner envelope triose phosphate/phosphate translocator.
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Affiliation(s)
- Robin G Walters
- Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
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19
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Walters RG, Rogers JJ, Shephard F, Horton P. Acclimation of Arabidopsis thaliana to the light environment: the role of photoreceptors. Planta 1999; 209:517-27. [PMID: 10550634 DOI: 10.1007/s004250050756] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The regulation by light of the composition of the photosynthetic apparatus was investigated in photomorphogenic mutants of Arabidopsis thaliana (L.) Heynh. cv. Landsberg erecta. Leaf chlorophyll, photosynthesis, photosystem II function, and ribulose-1, 5-bisphosphate carboxylase-oxygenase and photosystem II contents were determined for plants grown under high- or low-irradiance growth regimes. Although certain mutant lines had altered chloroplast composition compared to the wild type, all photoreceptor mutants tested were capable of light-dependent changes in chloroplast composition and photosynthetic function, indicating that photoreceptors do not play a central role in the regulation of acclimation at the level of the chloroplast. However, the clear acclimation defect in a det1 signal transduction mutant indicates that photoreceptor-controlled responses either share regulatory components with acclimation, or are important in the expression of components which in turn regulate acclimation. We suggest that the COP/DET/FUS regulatory cluster is a focus for multiple signal transduction pathways, including some of the metabolic signals which form the basis for the acclimatory response.
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Affiliation(s)
- R G Walters
- Robert Hill Institute, Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, Sheffield S10 2TN, UK.
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Jensen PE, Gibson LC, Shephard F, Smith V, Hunter CN. Introduction of a new branchpoint in tetrapyrrole biosynthesis in Escherichia coli by co-expression of genes encoding the chlorophyll-specific enzymes magnesium chelatase and magnesium protoporphyrin methyltransferase. FEBS Lett 1999; 455:349-54. [PMID: 10437802 DOI: 10.1016/s0014-5793(99)00909-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The genes encoding the three Mg chelatase subunits, ChlH, ChlI and ChlD, from the cyanobacterium Synechocystis PCC6803 were all cloned in the same pET9a-based Escherichia coli expression plasmid, forming an artificial chlH-I-D operon under the control of the strong T7 promoter. When a soluble extract from IPTG-induced E. coli cells containing the pET9a-ChlHID plasmid was assayed for Mg chelatase activity in vitro, a high activity was obtained, suggesting that all three subunits are present in a soluble and active form. The chlM gene of Synechocystis PCC6803 was also cloned in a pET-based E. coli expression vector. Soluble extract from an E. coli strain expressing chlM converted Mg-protoporphyrin IX to Mg-protoporphyrin monomethyl ester, demonstrating that chlM encodes the Mg-protoporphyrin methyltransferase of Synechocystis. Co-expression of the chlM gene together with the chlH-I-D construct yielded soluble protein extracts which converted protoporphyrin IX to Mg-protoporphyrin IX monomethyl ester without detectable accumulation of the Mg-protoporphyrin IX intermediate. Thus, active Mg chelatase and Mg-protoporphyrin IX methyltransferase can be coupled in E. coli extracts. Purified ChlI, -D and -H subunits in combination with purified ChlM protein were subsequently used to demonstrate in vitro that a molar ratio of ChlM to ChlH of 1 to 1 results in conversion of protoporphyrin IX to Mg-protoporphyrin monomethyl ester without significant accumulation of Mg-protoporphyrin.
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Affiliation(s)
- P E Jensen
- Department of Plant Biology, The Royal Veterinary and Agricultural University, Frederiksberg C, Denmark
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Abstract
fracture zone that ofisets the Mid-Atlantic Ridge at 24 degrees N, 45 degrees W was traced westward over a distance of 840 kilometers. The radius of curvature of the fracture zone changes at about 47 degrees 45'W; this suggests that the fracture zone was generated by rotation of crustal plates about at least two sequential poles.
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