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Katada Y, Yoshida K, Serizawa N, Lee D, Kobayashi K, Negishi K, Okano H, Kandori H, Tsubota K, Kurihara T. Highly sensitive visual restoration and protection via ectopic expression of chimeric rhodopsin in mice. iScience 2023; 26:107716. [PMID: 37720108 PMCID: PMC10504486 DOI: 10.1016/j.isci.2023.107716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 07/22/2023] [Accepted: 08/22/2023] [Indexed: 09/19/2023] Open
Abstract
Photoreception requires amplification by mammalian rhodopsin through G protein activation, which requires a visual cycle. To achieve this in retinal gene therapy, we incorporated human rhodopsin cytoplasmic loops into Gloeobacter rhodopsin, thereby generating Gloeobacter and human chimeric rhodopsin (GHCR). In a murine model of inherited retinal degeneration, we induced retinal GHCR expression by intravitreal injection of a recombinant adeno-associated virus vector. Retinal explant and visual thalamus electrophysiological recordings, behavioral tests, and histological analysis showed that GHCR restored dim-environment vision and prevented the progression of retinal degeneration. Thus, GHCR may be a potent clinical tool for the treatment of retinal disorders.
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Affiliation(s)
- Yusaku Katada
- Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Kazuho Yoshida
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Nagoya, Aichi 466-0061, Japan
| | - Naho Serizawa
- Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Nutritional Sciences, Toyo University, Kita-ku, Tokyo 115-8650, Japan
| | - Deokho Lee
- Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Kenta Kobayashi
- Section of Viral Vector Development, Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | - Kazuno Negishi
- Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Hideki Kandori
- Department of Life Science and Applied Chemistry, Nagoya Institute of Technology, Nagoya, Aichi 466-0061, Japan
| | - Kazuo Tsubota
- Tsubota Laboratory, Inc., Shinjuku-ku, Tokyo 160-0016, Japan
| | - Toshihide Kurihara
- Laboratory of Photobiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
- Department of Ophthalmology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
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Mason BM, Koyanagi M, Sugihara T, Iwasaki M, Slepak V, Miller DJ, Sakai Y, Terakita A. Multiple opsins in a reef-building coral, Acropora millepora. Sci Rep 2023; 13:1628. [PMID: 36710295 PMCID: PMC9884665 DOI: 10.1038/s41598-023-28476-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 01/19/2023] [Indexed: 01/30/2023] Open
Abstract
Opsins, light-sensitive G protein-coupled receptors, have been identified in corals but their properties are largely unknown. Here, we identified six opsin genes (acropsins 1-6) from a coral species Acropora millepora, including three novel opsins (acropsins 4-6), and successfully characterized the properties of four out of the six acropsins. Acropsins 1 and 6 exhibited light-dependent cAMP increases in cultured cells, suggesting that the acropsins could light-dependently activate Gs-type G protein like the box jellyfish opsin from the same opsin group. Spectral sensitivity curves having the maximum sensitivities at ~ 472 nm and ~ 476 nm were estimated for acropsins 1 and 6, respectively, based on the light wavelength-dependent cAMP increases in these opsins-expressing cells (heterologous action spectroscopy). Acropsin 2 belonging to the same group as acropsins 1 and 6 did not induce light-dependent cAMP or Ca2+ changes. We then successfully estimated the acropsin 2 spectral sensitivity curve having its maximum value at ~ 471 nm with its chimera mutant which possessed the third cytoplasmic loop of the Gs-coupled jellyfish opsin. Acropsin 4 categorized as another group light-dependently induced intracellular Ca2+ increases but not cAMP changes. Our results uncovered that the Acropora coral possesses multiple opsins coupling two distinct cascades, cyclic nucleotide and Ca2+signaling light-dependently.
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Affiliation(s)
- Benjamin M Mason
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD, 4811, Australia.,Molecular and Cell Biology, James Cook University, Townsville, QLD, 4811, Australia
| | - Mitsumasa Koyanagi
- Department of Biology and Geosciences, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.,The OCU Advanced Research Institute for Natural Science and Technology, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.,Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Tomohiro Sugihara
- Department of Biology and Geosciences, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.,Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Makoto Iwasaki
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Vladlen Slepak
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - David J Miller
- Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, Townsville, QLD, Australia.,Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Okinawa, 904-0495, Japan
| | - Yusuke Sakai
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan
| | - Akihisa Terakita
- Department of Biology and Geosciences, Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan. .,The OCU Advanced Research Institute for Natural Science and Technology, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan. .,Department of Biology, Graduate School of Science, Osaka Metropolitan University, 3-3-138 Sugimoto, Sumiyoshi-Ku, Osaka, 558-8585, Japan.
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High-performance optical control of GPCR signaling by bistable animal opsins MosOpn3 and LamPP in a molecular property-dependent manner. Proc Natl Acad Sci U S A 2022; 119:e2204341119. [PMID: 36417444 PMCID: PMC9889881 DOI: 10.1073/pnas.2204341119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Optical control of G protein-coupled receptor (GPCR) signaling is a highly valuable approach for comprehensive understanding of GPCR-based physiologies and controlling them precisely. However, optogenetics for GPCR signaling is still developing and requires effective and versatile tools with performance evaluation from their molecular properties. Here, we systematically investigated performance of two bistable opsins that activate Gi/Go-type G protein (mosquito Opn3 (MosOpn3) and lamprey parapinopsin (LamPP)) in optical control in vivo using Caenorhabditis elegans. Transgenic worms expressing MosOpn3, which binds 13-cis retinal to form photopigments, in nociceptor neurons showed light-induced avoidance responses in the presence of all-trans retinal, a retinal isomer ubiquitously present in every tissue, like microbial rhodopsins and unlike canonical vertebrate opsins. Remarkably, transgenic worms expressing MosOpn3 were ~7,000 times more sensitive to light than transgenic worms expressing ChR2 in this light-induced behavior, demonstrating the advantage of MosOpn3 as a light switch. LamPP is a UV-sensitive bistable opsin having complete photoregenerative ability by green light. Accordingly, transgenic worms expressing LamPP in cholinergic motor neurons stopped moving upon violet light illumination and restored coordinate movement upon green light illumination, demonstrating color-dependent control of behavior using LamPP. Furthermore, we applied molecular engineering to produce MosOpn3-based tools enabling light-dependent upregulation of cAMP or Ca2+ levels and LamPP-based tool enabling clamping cAMP levels color dependently and context independently, extending their usability. These findings define the capacity of two bistable opsins with similar retinal requirement as ChR2, providing numerous strategies for optical control of various GPCR-based physiologies as well as GPCR signaling itself.
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de Grip WJ, Ganapathy S. Rhodopsins: An Excitingly Versatile Protein Species for Research, Development and Creative Engineering. Front Chem 2022; 10:879609. [PMID: 35815212 PMCID: PMC9257189 DOI: 10.3389/fchem.2022.879609] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Accepted: 05/16/2022] [Indexed: 01/17/2023] Open
Abstract
The first member and eponym of the rhodopsin family was identified in the 1930s as the visual pigment of the rod photoreceptor cell in the animal retina. It was found to be a membrane protein, owing its photosensitivity to the presence of a covalently bound chromophoric group. This group, derived from vitamin A, was appropriately dubbed retinal. In the 1970s a microbial counterpart of this species was discovered in an archaeon, being a membrane protein also harbouring retinal as a chromophore, and named bacteriorhodopsin. Since their discovery a photogenic panorama unfolded, where up to date new members and subspecies with a variety of light-driven functionality have been added to this family. The animal branch, meanwhile categorized as type-2 rhodopsins, turned out to form a large subclass in the superfamily of G protein-coupled receptors and are essential to multiple elements of light-dependent animal sensory physiology. The microbial branch, the type-1 rhodopsins, largely function as light-driven ion pumps or channels, but also contain sensory-active and enzyme-sustaining subspecies. In this review we will follow the development of this exciting membrane protein panorama in a representative number of highlights and will present a prospect of their extraordinary future potential.
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Affiliation(s)
- Willem J. de Grip
- Leiden Institute of Chemistry, Department of Biophysical Organic Chemistry, Leiden University, Leiden, Netherlands
- Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Srividya Ganapathy
- Department of Imaging Physics, Delft University of Technology, Netherlands
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Wang B, Hao X, Xu J, Ma Y, Ma L. Transcriptome-Based Analysis Reveals a Crucial Role of BxGPCR17454 in Low Temperature Response of Pine Wood Nematode ( Bursaphelenchus xylophilus). Int J Mol Sci 2019; 20:ijms20122898. [PMID: 31197083 PMCID: PMC6628231 DOI: 10.3390/ijms20122898] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/06/2019] [Accepted: 06/11/2019] [Indexed: 12/02/2022] Open
Abstract
Background: The causal agent of pine wilt disease is the pine wood nematode (PWN) (Bursaphelenchus xylophilus), whose ability to adapt different ecological niches is a crucial determinant of their invasion to colder regions. To discover the molecular mechanism of low temperature response mechanism, we attempted to study the molecular response patterns under low temperature from B. xylophilus with a comprehensive RNA sequencing analysis and validated the differentially expressed genes (DEGs) with quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatic software was utilized to isolate and identify the low-temperature-related BxGPCR genes. Transcript abundance of six low-temperature-related BxGPCR genes and function of one of the BxGPCR genes are studied by qRT-PCR and RNA interference. Results: The results showed that we detected 432 DEGs through RNA sequencing between low-temperature-treated and ambient-temperature-treated groups nematodes. The transcript level of 6 low-temperature-related BxGPCR genes increased at low temperature. And, the survival rates of BxGPCR17454 silenced B. xylophilus revealed a significant decrease at low temperature. Conclusion: in conclusion, this transcriptome-based study revealed a crucial role of BxGPCR17454 in low temperature response process of pine wood nematode. These discoveries would assist the development of management and methods for efficient control of this devastating pine tree pest.
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Affiliation(s)
- Bowen Wang
- College of Forestry, Northeast Forestry University, Harbin 150040, China.
| | - Xin Hao
- College of Forestry, Northeast Forestry University, Harbin 150040, China.
| | - Jiayao Xu
- College of Forestry, Northeast Forestry University, Harbin 150040, China.
| | - Yan Ma
- College of Management, Harbin University of Commerce, Harbin 150028, China.
| | - Ling Ma
- College of Forestry, Northeast Forestry University, Harbin 150040, China.
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Eickelbeck D, Karapinar R, Herlitze S, Spoida K. Optogenetic Approaches for Controlling Neuronal Activity and Plasticity. HANDBOOK OF BEHAVIORAL NEUROSCIENCE 2018. [DOI: 10.1016/b978-0-12-812028-6.00016-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Ethanol Stimulates Locomotion via a G αs-Signaling Pathway in IL2 Neurons in Caenorhabditis elegans. Genetics 2017; 207:1023-1039. [PMID: 28951527 PMCID: PMC5676223 DOI: 10.1534/genetics.117.300119] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/23/2017] [Indexed: 01/21/2023] Open
Abstract
Alcohol abuse is among the top causes of preventable death, generating considerable financial, health, and societal burdens. Paradoxically, alcohol... Alcohol is a potent pharmacological agent when consumed acutely at sufficient quantities and repeated overuse can lead to addiction and deleterious effects on health. Alcohol is thought to modulate neuronal function through low-affinity interactions with proteins, in particular with membrane channels and receptors. Paradoxically, alcohol acts as both a stimulant and a sedative. The exact molecular mechanisms for the acute effects of ethanol on neurons, as either a stimulant or a sedative, however remain unclear. We investigated the role that the heat shock transcription factor HSF-1 played in determining a stimulatory phenotype of Caenorhabditis elegans in response to physiologically relevant concentrations of ethanol (17 mM; 0.1% v/v). Using genetic techniques, we demonstrate that either RNA interference of hsf-1 or use of an hsf-1(sy441) mutant lacked the enhancement of locomotion in response to acute ethanol exposure evident in wild-type animals. We identify that the requirement for HSF-1 in this phenotype was IL2 neuron-specific and required the downstream expression of the α-crystallin ortholog HSP-16.48. Using a combination of pharmacology, optogenetics, and phenotypic analyses we determine that ethanol activates a Gαs-cAMP-protein kinase A signaling pathway in IL2 neurons to stimulate nematode locomotion. We further implicate the phosphorylation of a specific serine residue (Ser322) on the synaptic protein UNC-18 as an end point for the Gαs-dependent signaling pathway. These findings establish and characterize a distinct neurosensory cell signaling pathway that determines the stimulatory action of ethanol and identifies HSP-16.48 and HSF-1 as novel regulators of this pathway.
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8
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Delroisse J, Mallefet J, Flammang P. De Novo Adult Transcriptomes of Two European Brittle Stars: Spotlight on Opsin-Based Photoreception. PLoS One 2016; 11:e0152988. [PMID: 27119739 PMCID: PMC4847921 DOI: 10.1371/journal.pone.0152988] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 03/22/2016] [Indexed: 11/19/2022] Open
Abstract
Next generation sequencing (NGS) technology allows to obtain a deeper and more complete view of transcriptomes. For non-model or emerging model marine organisms, NGS technologies offer a great opportunity for rapid access to genetic information. In this study, paired-end Illumina HiSeqTM technology has been employed to analyse transcriptomes from the arm tissues of two European brittle star species, Amphiura filiformis and Ophiopsila aranea. About 48 million Illumina reads were generated and 136,387 total unigenes were predicted from A. filiformis arm tissues. For O. aranea arm tissues, about 47 million reads were generated and 123,324 total unigenes were obtained. Twenty-four percent of the total unigenes from A. filiformis show significant matches with sequences present in reference online databases, whereas, for O. aranea, this percentage amounts to 23%. In both species, around 50% of the predicted annotated unigenes were significantly similar to transcripts from the purple sea urchin, the closest species to date that has undergone complete genome sequencing and annotation. GO, COG and KEGG analyses were performed on predicted brittle star unigenes. We focused our analyses on the phototransduction actors involved in light perception. Firstly, two new echinoderm opsins were identified in O. aranea: one rhabdomeric opsin (homologous to vertebrate melanopsin) and one RGR opsin. The RGR-opsin is supposed to be involved in retinal regeneration while the r-opsin is suspected to play a role in visual-like behaviour. Secondly, potential phototransduction actors were identified in both transcriptomes using the fly (rhabdomeric) and mammal (ciliary) classical phototransduction pathways as references. Finally, the sensitivity of O.aranea to monochromatic light was investigated to complement data available for A. filiformis. The presence of microlens-like structures at the surface of dorsal arm plate of O. aranea could potentially explain phototactic behaviour differences between the two species. The results confirm (i) the ability of these brittle stars to perceive light using opsin-based photoreception, (ii) suggest the co-occurrence of both rhabdomeric and ciliary photoreceptors, and (iii) emphasise the complexity of light perception in this echinoderm class.
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Affiliation(s)
- Jérôme Delroisse
- School of Biological & Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Jérôme Mallefet
- Catholic University of Louvain-La-Neuve, Marine Biology Laboratory, Place croix du Sud, Louvain-La-Neuve–Belgium
| | - Patrick Flammang
- University of Mons—UMONS, Research Institute for Biosciences, Biology of Marine Organisms and Biomimetics, Mons, Belgium
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Tsukamoto T, Mizutani K, Hasegawa T, Takahashi M, Honda N, Hashimoto N, Shimono K, Yamashita K, Yamamoto M, Miyauchi S, Takagi S, Hayashi S, Murata T, Sudo Y. X-ray Crystallographic Structure of Thermophilic Rhodopsin: IMPLICATIONS FOR HIGH THERMAL STABILITY AND OPTOGENETIC FUNCTION. J Biol Chem 2016; 291:12223-32. [PMID: 27129243 DOI: 10.1074/jbc.m116.719815] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Indexed: 01/01/2023] Open
Abstract
Thermophilic rhodopsin (TR) is a photoreceptor protein with an extremely high thermal stability and the first characterized light-driven electrogenic proton pump derived from the extreme thermophile Thermus thermophilus JL-18. In this study, we confirmed its high thermal stability compared with other microbial rhodopsins and also report the potential availability of TR for optogenetics as a light-induced neural silencer. The x-ray crystal structure of TR revealed that its overall structure is quite similar to that of xanthorhodopsin, including the presence of a putative binding site for a carotenoid antenna; but several distinct structural characteristics of TR, including a decreased surface charge and a larger number of hydrophobic residues and aromatic-aromatic interactions, were also clarified. Based on the crystal structure, the structural changes of TR upon thermal stimulation were investigated by molecular dynamics simulations. The simulations revealed the presence of a thermally induced structural substate in which an increase of hydrophobic interactions in the extracellular domain, the movement of extracellular domains, the formation of a hydrogen bond, and the tilting of transmembrane helices were observed. From the computational and mutational analysis, we propose that an extracellular LPGG motif between helices F and G plays an important role in the thermal stability, acting as a "thermal sensor." These findings will be valuable for understanding retinal proteins with regard to high protein stability and high optogenetic performance.
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Affiliation(s)
- Takashi Tsukamoto
- From the Division of Pharmaceutical Sciences, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan
| | - Kenji Mizutani
- the Department of Chemistry, Graduate School of Science, Chiba University, Chiba 263-8522, Japan, the Molecular Chirality Research Center, Chiba University, Chiba 263-8522, Japan
| | - Taisuke Hasegawa
- the Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Megumi Takahashi
- the Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Naoya Honda
- From the Division of Pharmaceutical Sciences, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan
| | - Naoki Hashimoto
- the Department of Chemistry, Graduate School of Science, Chiba University, Chiba 263-8522, Japan
| | - Kazumi Shimono
- the Faculty of Pharmaceutical Sciences, Toho University, Funabashi 274-8510, Japan, and
| | | | | | - Seiji Miyauchi
- the Faculty of Pharmaceutical Sciences, Toho University, Funabashi 274-8510, Japan, and
| | - Shin Takagi
- the Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya 464-8602, Japan
| | - Shigehiko Hayashi
- the Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Takeshi Murata
- the Department of Chemistry, Graduate School of Science, Chiba University, Chiba 263-8522, Japan, the Molecular Chirality Research Center, Chiba University, Chiba 263-8522, Japan,
| | - Yuki Sudo
- From the Division of Pharmaceutical Sciences, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan,
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10
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Yuan Y, Hakimi P, Kao C, Kao A, Liu R, Janocha A, Boyd-Tressler A, Hang X, Alhoraibi H, Slater E, Xia K, Cao P, Shue Q, Ching TT, Hsu AL, Erzurum SC, Dubyak GR, Berger NA, Hanson RW, Feng Z. Reciprocal Changes in Phosphoenolpyruvate Carboxykinase and Pyruvate Kinase with Age Are a Determinant of Aging in Caenorhabditis elegans. J Biol Chem 2016; 291:1307-19. [PMID: 26631730 PMCID: PMC4714217 DOI: 10.1074/jbc.m115.691766] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 11/30/2015] [Indexed: 01/01/2023] Open
Abstract
Aging involves progressive loss of cellular function and integrity, presumably caused by accumulated stochastic damage to cells. Alterations in energy metabolism contribute to aging, but how energy metabolism changes with age, how these changes affect aging, and whether they can be modified to modulate aging remain unclear. In locomotory muscle of post-fertile Caenorhabditis elegans, we identified a progressive decrease in cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C), a longevity-associated metabolic enzyme, and a reciprocal increase in glycolytic pyruvate kinase (PK) that were necessary and sufficient to limit lifespan. Decline in PEPCK-C with age also led to loss of cellular function and integrity including muscle activity, and cellular senescence. Genetic and pharmacologic interventions of PEPCK-C, muscle activity, and AMPK signaling demonstrate that declines in PEPCK-C and muscle function with age interacted to limit reproductive life and lifespan via disrupted energy homeostasis. Quantifications of metabolic flux show that reciprocal changes in PEPCK-C and PK with age shunted energy metabolism toward glycolysis, reducing mitochondrial bioenergetics. Last, calorie restriction countered changes in PEPCK-C and PK with age to elicit anti-aging effects via TOR inhibition. Thus, a programmed metabolic event involving PEPCK-C and PK is a determinant of aging that can be modified to modulate aging.
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Affiliation(s)
| | | | - Clara Kao
- From the Departments of Pharmacology
| | | | - Ruifu Liu
- From the Departments of Pharmacology
| | - Allison Janocha
- the Department of Pathobiology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio 44195
| | | | - Xi Hang
- From the Departments of Pharmacology, the School of Pharmacy, Suzhou Health College, Suzhou, Jiangsu 215009, China, and
| | | | | | - Kevin Xia
- From the Departments of Pharmacology
| | | | | | - Tsui-Ting Ching
- the Departments of Internal Medicine, Division of Geriatric Medicine, and
| | - Ao-Lin Hsu
- the Departments of Internal Medicine, Division of Geriatric Medicine, and Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan 48109
| | - Serpil C Erzurum
- the Department of Pathobiology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio 44195
| | - George R Dubyak
- From the Departments of Pharmacology, Physiology and Biophysics, and
| | - Nathan A Berger
- Departments of Biochemistry and Medicine, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106
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Abstract
The discovery of light-gated ion channels and their application to controlling neural activities have had a transformative impact on the field of neuroscience. In recent years, the concept of using light-activated proteins to control biological processes has greatly diversified into other fields, driven by the natural diversity of photoreceptors and decades of knowledge obtained from their biophysical characterization. In this chapter, we will briefly discuss the origin and development of optogenetics and highlight the basic concepts that make it such a powerful technology. We will review how these enabling concepts have developed over the past decade, and discuss future perspectives.
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Affiliation(s)
- Yong Ku Cho
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT, USA. .,Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA.
| | - Dan Li
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT, USA
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12
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Metabotropic GABA signalling modulates longevity in C. elegans. Nat Commun 2015; 6:8828. [PMID: 26537867 PMCID: PMC4667614 DOI: 10.1038/ncomms9828] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Accepted: 10/08/2015] [Indexed: 02/05/2023] Open
Abstract
The nervous system plays an important but poorly understood role in modulating longevity. GABA, a prominent inhibitory neurotransmitter, is best known to regulate nervous system function and behaviour in diverse organisms. Whether GABA signalling affects aging, however, has not been explored. Here we examined mutants lacking each of the major neurotransmitters in C. elegans, and find that deficiency in GABA signalling extends lifespan. This pro-longevity effect is mediated by the metabotropic GABAB receptor GBB-1, but not ionotropic GABAA receptors. GBB-1 regulates lifespan through G protein-PLCβ signalling, which transmits longevity signals to the transcription factor DAF-16/FOXO, a key regulator of lifespan. Mammalian GABAB receptors can functionally substitute for GBB-1 in lifespan control in C. elegans. Our results uncover a new role of GABA signalling in lifespan regulation in C. elegans, raising the possibility that a similar process may occur in other organisms. The C. elegans nervous system influences organismal lifespan but mechanistic details are poorly understood. Here, Chun et al. show that the neurotransmitter GABA regulates worm lifespan by acting on GABAB receptors in motor neurons, which activate the transcription factor DAF-16 in the intestine.
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13
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Van Gelder RN, Kaur K. Vision Science: Can Rhodopsin Cure Blindness? Curr Biol 2015; 25:R713-5. [PMID: 26294183 DOI: 10.1016/j.cub.2015.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Outer retinal degeneration is the leading cause of blindness in the developed world. A new study now demonstrates that ectopic expression of human rhodopsin in the inner retina, mediated by viral gene therapy, can restore light sensitivity and some vision to mice blind from outer retinal degeneration.
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Affiliation(s)
- Russell N Van Gelder
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98104, USA; Department of Biological Structure, University of Washington School of Medicine, Seattle, WA 98104, USA; Department of Pathology, University of Washington School of Medicine, Seattle, WA 98104, USA.
| | - Kuldeep Kaur
- Department of Ophthalmology, University of Washington School of Medicine, Seattle, WA 98104, USA
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14
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Cehajic-Kapetanovic J, Eleftheriou C, Allen AE, Milosavljevic N, Pienaar A, Bedford R, Davis KE, Bishop PN, Lucas RJ. Restoration of Vision with Ectopic Expression of Human Rod Opsin. Curr Biol 2015; 25:2111-22. [PMID: 26234216 PMCID: PMC4540256 DOI: 10.1016/j.cub.2015.07.029] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 06/19/2015] [Accepted: 07/10/2015] [Indexed: 11/10/2022]
Abstract
Many retinal dystrophies result in photoreceptor loss, but the inner retinal neurons can survive, making them potentially amenable to emerging optogenetic therapies. Here, we show that ectopically expressed human rod opsin, driven by either a non-selective or ON-bipolar cell-specific promoter, can function outside native photoreceptors and restore visual function in a mouse model of advanced retinal degeneration. Electrophysiological recordings from retinal explants and the visual thalamus revealed changes in firing (increases and decreases) induced by simple light pulses, luminance increases, and naturalistic movies in treated mice. These responses could be elicited at light intensities within the physiological range and substantially below those required by other optogenetic strategies. Mice with rod opsin expression driven by the ON-bipolar specific promoter displayed behavioral responses to increases in luminance, flicker, coarse spatial patterns, and elements of a natural movie at levels of contrast and illuminance (≈50–100 lux) typical of natural indoor environments. These data reveal that virally mediated ectopic expression of human rod opsin can restore vision under natural viewing conditions and at moderate light intensities. Given the inherent advantages in employing a human protein, the simplicity of this intervention, and the quality of vision restored, we suggest that rod opsin merits consideration as an optogenetic actuator for treating patients with advanced retinal degeneration. Ectopic human rod opsin restores visual functions in advanced retinal degeneration Rod opsin has greater sensitivity than current optogenetic strategies Rod opsin-treated animals respond to spatial stimuli, flicker, and natural scenes As a human protein ordinarily found in retinal tissue, barriers to clinic are minimized
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Affiliation(s)
- Jasmina Cehajic-Kapetanovic
- Centre for Ophthalmology and Vision Sciences, Institute of Human Development, University of Manchester, Manchester M13 9PT, UK; Manchester Royal Eye Hospital, CMFT, Manchester Academic Health Sciences Centre, Manchester M13 9NT, UK
| | - Cyril Eleftheriou
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Annette E Allen
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Nina Milosavljevic
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Abigail Pienaar
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Robert Bedford
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Katherine E Davis
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK
| | - Paul N Bishop
- Centre for Ophthalmology and Vision Sciences, Institute of Human Development, University of Manchester, Manchester M13 9PT, UK; Manchester Royal Eye Hospital, CMFT, Manchester Academic Health Sciences Centre, Manchester M13 9NT, UK.
| | - Robert J Lucas
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, UK.
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15
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Optogenetic Vision Restoration Using Rhodopsin for Enhanced Sensitivity. Mol Ther 2015; 23:1562-71. [PMID: 26137852 PMCID: PMC4817926 DOI: 10.1038/mt.2015.121] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 06/22/2015] [Indexed: 12/26/2022] Open
Abstract
Retinal disease is one of the most active areas of gene therapy, with clinical trials ongoing in the United States for five diseases. There are currently no treatments for patients with late-stage disease in which photoreceptors have been lost. Optogenetic gene therapies are in development, but, to date, have suffered from the low light sensitivity of microbial opsins, such as channelrhodopsin and halorhodopsin, and azobenzene-based photoswitches. Several groups have shown that photoreceptive G-protein-coupled receptors (GPCRs) can be expressed heterologously, and photoactivate endogenous Gi/o signaling. We hypothesized such a GPCR could increase sensitivity due to endogenous signal amplification. We targeted vertebrate rhodopsin to retinal ON-bipolar cells of blind rd1 mice and observed restoration of: (i) light responses in retinal explants, (ii) visually-evoked potentials in visual cortex in vivo, and (iii) two forms of visually-guided behavior: innate light avoidance and discrimination of temporal light patterns in the context of fear conditioning. Importantly, both the light responses of the retinal explants and the visually-guided behavior occurred reliably at light levels that were two to three orders of magnitude dimmer than required for channelrhodopsin. Thus, gene therapy with native light-gated GPCRs presents a novel approach to impart light sensitivity for visual restoration in a useful range of illumination.
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16
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Abstract
Rhodopsin is a key light-sensitive protein expressed exclusively in rod photoreceptor cells of the retina. Failure to express this transmembrane protein causes a lack of rod outer segment formation and progressive retinal degeneration, including the loss of cone photoreceptor cells. Molecular studies of rhodopsin have paved the way to understanding a large family of cell-surface membrane proteins called G protein-coupled receptors (GPCRs). Work started on rhodopsin over 100 years ago still continues today with substantial progress made every year. These activities underscore the importance of rhodopsin as a prototypical GPCR and receptor required for visual perception-the fundamental process of translating light energy into a biochemical cascade of events culminating in vision.
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Affiliation(s)
- Lukas Hofmann
- Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH, 44106, USA
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17
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Isotopic labeling of mammalian G protein-coupled receptors heterologously expressed in Caenorhabditis elegans. Anal Biochem 2014; 472:30-6. [PMID: 25461480 DOI: 10.1016/j.ab.2014.11.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 11/10/2014] [Accepted: 11/13/2014] [Indexed: 12/28/2022]
Abstract
High-resolution structural determination and dynamic characterization of membrane proteins by nuclear magnetic resonance (NMR) require their isotopic labeling. Although a number of labeled eukaryotic membrane proteins have been successfully expressed in bacteria, they lack post-translational modifications and usually need to be refolded from inclusion bodies. This shortcoming of bacterial expression systems is particularly detrimental for the functional expression of G protein-coupled receptors (GPCRs), the largest family of drug targets, due to their inherent instability. In this work, we show that proteins expressed by a eukaryotic organism can be isotopically labeled and produced with a quality and quantity suitable for NMR characterization. Using our previously described expression system in Caenorhabditis elegans, we showed the feasibility of labeling proteins produced by these worms with (15)N,(13)C by providing them with isotopically labeled bacteria. (2)H labeling also was achieved by growing C. elegans in the presence of 70% heavy water. Bovine rhodopsin, simultaneously expressed in muscular and neuronal worm tissues, was employed as the "test" GPCR to demonstrate the viability of this approach. Although the worms' cell cycle was slightly affected by the presence of heavy isotopes, the final protein yield and quality was appropriate for NMR structural characterization.
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18
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Chen Y, Jastrzebska B, Cao P, Zhang J, Wang B, Sun W, Yuan Y, Feng Z, Palczewski K. Inherent instability of the retinitis pigmentosa P23H mutant opsin. J Biol Chem 2014; 289:9288-303. [PMID: 24515108 PMCID: PMC3979360 DOI: 10.1074/jbc.m114.551713] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 02/05/2014] [Indexed: 11/06/2022] Open
Abstract
The P23H opsin mutation is the most common cause of autosomal dominant retinitis pigmentosa. Even though the pathobiology of the resulting retinal degeneration has been characterized in several animal models, its complex molecular mechanism is not well understood. Here, we expressed P23H bovine rod opsin in the nervous system of Caenorhabditis elegans. Expression was low due to enhanced protein degradation. The mutant opsin was glycosylated, but the polysaccharide size differed from that of the normal protein. Although P23H opsin aggregated in the nervous system of C. elegans, the pharmacological chaperone 9-cis-retinal stabilized it during biogenesis, producing a variant of rhodopsin called P23H isorhodopsin. In vitro, P23H isorhodopsin folded correctly, formed the appropriate disulfide bond, could be photoactivated but with reduced sensitivity, and underwent Meta II decay at a rate similar to wild type isorhodopsin. In worm neurons, P23H isorhodopsin initiated phototransduction by coupling with the endogenous Gi/o signaling cascade that induced loss of locomotion. Using pharmacological interventions affecting protein synthesis and degradation, we showed that the chromophore could be incorporated either during or after mutant protein translation. However, regeneration of P23H isorhodopsin with chromophore was significantly slower than that of wild type isorhodopsin. This effect, combined with the inherent instability of P23H rhodopsin, could lead to the structural cellular changes and photoreceptor death found in autosomal dominant retinitis pigmentosa. These results also suggest that slow regeneration of P23H rhodopsin could prevent endogenous chromophore-mediated stabilization of rhodopsin in the retina.
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Affiliation(s)
| | | | | | | | - Benlian Wang
- Center for Proteomics and Bioinformatics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4965 and
| | - Wenyu Sun
- Polgenix Inc., Cleveland, Ohio 44106
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19
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Chen Y, Palczewska G, Mustafi D, Golczak M, Dong Z, Sawada O, Maeda T, Maeda A, Palczewski K. Systems pharmacology identifies drug targets for Stargardt disease-associated retinal degeneration. J Clin Invest 2013; 123:5119-34. [PMID: 24231350 DOI: 10.1172/jci69076] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 09/12/2013] [Indexed: 12/22/2022] Open
Abstract
A systems pharmacological approach that capitalizes on the characterization of intracellular signaling networks can transform our understanding of human diseases and lead to therapy development. Here, we applied this strategy to identify pharmacological targets for the treatment of Stargardt disease, a severe juvenile form of macular degeneration. Diverse GPCRs have previously been implicated in neuronal cell survival, and crosstalk between GPCR signaling pathways represents an unexplored avenue for pharmacological intervention. We focused on this receptor family for potential therapeutic interventions in macular disease. Complete transcriptomes of mouse and human samples were analyzed to assess the expression of GPCRs in the retina. Focusing on adrenergic (AR) and serotonin (5-HT) receptors, we found that adrenoceptor α 2C (Adra2c) and serotonin receptor 2a (Htr2a) were the most highly expressed. Using a mouse model of Stargardt disease, we found that pharmacological interventions that targeted both GPCR signaling pathways and adenylate cyclases (ACs) improved photoreceptor cell survival, preserved photoreceptor function, and attenuated the accumulation of pathological fluorescent deposits in the retina. These findings demonstrate a strategy for the identification of new drug candidates and FDA-approved drugs for the treatment of monogenic and complex diseases.
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MESH Headings
- ATP-Binding Cassette Transporters/deficiency
- ATP-Binding Cassette Transporters/genetics
- Adenine/analogs & derivatives
- Adenine/pharmacology
- Adenine/therapeutic use
- Adenylyl Cyclase Inhibitors
- Adrenergic alpha-Agonists/pharmacology
- Adrenergic alpha-Agonists/therapeutic use
- Adrenergic alpha-Antagonists/pharmacology
- Adrenergic alpha-Antagonists/therapeutic use
- Alcohol Oxidoreductases/deficiency
- Alcohol Oxidoreductases/genetics
- Animals
- Cell Survival
- Disease Models, Animal
- Doxazosin/pharmacology
- Doxazosin/therapeutic use
- Drug Evaluation, Preclinical
- Guanabenz/pharmacology
- Guanabenz/therapeutic use
- Humans
- Light/adverse effects
- Macaca fascicularis
- Macular Degeneration/congenital
- Macular Degeneration/drug therapy
- Macular Degeneration/genetics
- Macular Degeneration/prevention & control
- Mice
- Mice, Inbred BALB C
- Mice, Knockout
- Molecular Targeted Therapy
- Nerve Tissue Proteins/biosynthesis
- Nerve Tissue Proteins/genetics
- Photoreceptor Cells, Vertebrate/drug effects
- Photoreceptor Cells, Vertebrate/pathology
- Photoreceptor Cells, Vertebrate/physiology
- Photoreceptor Cells, Vertebrate/radiation effects
- Reactive Oxygen Species
- Receptor, Serotonin, 5-HT2A/biosynthesis
- Receptor, Serotonin, 5-HT2A/genetics
- Receptors, Adrenergic, alpha-2/biosynthesis
- Receptors, Adrenergic, alpha-2/genetics
- Receptors, G-Protein-Coupled/biosynthesis
- Receptors, G-Protein-Coupled/genetics
- Serotonin Antagonists/pharmacology
- Serotonin Antagonists/therapeutic use
- Signal Transduction
- Stargardt Disease
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20
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Palczewski K, Orban T. From atomic structures to neuronal functions of g protein-coupled receptors. Annu Rev Neurosci 2013; 36:139-64. [PMID: 23682660 DOI: 10.1146/annurev-neuro-062012-170313] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
G protein-coupled receptors (GPCRs) are essential mediators of signal transduction, neurotransmission, ion channel regulation, and other cellular events. GPCRs are activated by diverse stimuli, including light, enzymatic processing of their N-termini, and binding of proteins, peptides, or small molecules such as neurotransmitters. GPCR dysfunction caused by receptor mutations and environmental challenges contributes to many neurological diseases. Moreover, modern genetic technology has helped identify a rich array of mono- and multigenic defects in humans and animal models that connect such receptor dysfunction with disease affecting neuronal function. The visual system is especially suited to investigate GPCR structure and function because advanced imaging techniques permit structural studies of photoreceptor neurons at both macro and molecular levels that, together with biochemical and physiological assessment in animal models, provide a more complete understanding of GPCR signaling.
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Affiliation(s)
- Krzysztof Palczewski
- Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4965, USA.
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21
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Abstract
Constituting the largest group of membrane proteins identified in the human genome, G protein-coupled receptors (GPCRs) help control many physiological processes by responding to various stimuli. As targets for more than 40% of all prescribed pharmaceuticals, detailed understanding of GPCR structures is vital for the design and development of more specific medications and improved patient therapies. But structural information for membrane proteins and GPCRs, in particular, is limited despite considerable interest. The major impediment to obtaining sufficient quantities of highly purified GPCRs in their native form for crystallization lies in their low tissue levels, poor yields, and stability. The only exception is rhodopsin, which is abundantly expressed in the eye and stabilized by its covalently bound chromophore, 11-cis-retinal. Expression systems and purification protocols have yet to be developed for all other GPCRs. Here, we present a novel expression system for human GPCRs in Caenorhabditis elegans that produces sufficient amounts of recombinant proteins to allow their biochemical and structural characterization.
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22
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Salom D, Cao P, Sun W, Kramp K, Jastrzebska B, Jin H, Feng Z, Palczewski K. Heterologous expression of functional G-protein-coupled receptors in Caenorhabditis elegans. FASEB J 2011; 26:492-502. [PMID: 22090314 DOI: 10.1096/fj.11-197780] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
New strategies for expression, purification, functional characterization, and structural determination of membrane-spanning G-protein-coupled receptors (GPCRs) are constantly being developed because of their importance to human health. Here, we report a Caenorhabditis elegans heterologous expression system able to produce milligram amounts of functional native and engineered GPCRs. Both bovine opsin [(b)opsin] and human adenosine A(2A) subtype receptor [(h)A(2A)R] expressed in neurons or muscles of C. elegans were localized to cell membranes. Worms expressing these GPCRs manifested changes in motor behavior in response to light and ligands, respectively. With a newly devised protocol, 0.6-1 mg of purified homogenous 9-cis-retinal-bound bovine isorhodopsin [(b)isoRho] and ligand-bound (h)A(2A)R were obtained from C. elegans from one 10-L fermentation at low cost. Purified recombinant (b)isoRho exhibited its signature absorbance spectrum and activated its cognate G-protein transducin in vitro at a rate similar to native rhodopsin (Rho) obtained from bovine retina. Generally high expression levels of 11 native and mutant GPCRs demonstrated the potential of this C. elegans system to produce milligram quantities of high-quality GPCRs and possibly other membrane proteins suitable for detailed characterization.
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