1
|
Cao X, Xie Y, Yang H, Sun P, Xue B, Garcia LR, Zhang L. EAT-2 attenuates C. elegans development via metabolic remodeling in a chemically defined food environment. Cell Mol Life Sci 2023; 80:205. [PMID: 37450052 DOI: 10.1007/s00018-023-04849-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/29/2023] [Accepted: 06/25/2023] [Indexed: 07/18/2023]
Abstract
Dietary intake and nutrient composition regulate animal growth and development; however, the underlying mechanisms remain elusive. Our previous study has shown that either the mammalian deafness homolog gene tmc-1 or its downstream acetylcholine receptor gene eat-2 attenuates Caenorhabditis elegans development in a chemically defined food CeMM (C. elegans maintenance medium) environment, but the underpinning mechanisms are not well-understood. Here, we found that, in CeMM food environment, for both eat-2 and tmc-1 fast-growing mutants, several fatty acid synthesis and elongation genes were highly expressed, while many fatty acid β-oxidation genes were repressed. Accordingly, dietary supplementation of individual fatty acids, such as monomethyl branch chain fatty acid C17ISO, palmitic acid and stearic acid significantly promoted wild-type animal development on CeMM, and mutations in either C17ISO synthesis gene elo-5 or elo-6 slowed the rapid growth of eat-2 mutant. Tissue-specific rescue experiments showed that elo-6 promoted animal development mainly in the intestine. Furthermore, transcriptome and metabolome analyses revealed that elo-6/C17ISO regulation of C. elegans development may be correlated with up-regulating expression of cuticle synthetic and hedgehog signaling genes, as well as promoting biosynthesis of amino acids, amino acid derivatives and vitamins. Correspondingly, we found that amino acid derivative S-adenosylmethionine and its upstream metabolite methionine sulfoxide significantly promoted C. elegans development on CeMM. This study demonstrated that C17ISO, palmitic acid, stearic acid, S-adenosylmethionine and methionine sulfoxide inhibited or bypassed the TMC-1 and EAT-2-mediated attenuation of development via metabolic remodeling, and allowed the animals to adapt to the new nutritional niche.
Collapse
Affiliation(s)
- Xuwen Cao
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266237, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, 266071, Qingdao, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
- Institute of Marine Science and Technology, Shandong University, 72 Binhai Road, 266237, Qingdao, China
| | - Yusu Xie
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266237, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, 266071, Qingdao, China
| | - Hanwen Yang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266237, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, 266071, Qingdao, China
| | - Peiqi Sun
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266237, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, 266071, Qingdao, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Beining Xue
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266237, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, 266071, Qingdao, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - L Rene Garcia
- Department of Biology, Texas A&M University, College Station, TX, 77843-3258, USA
| | - Liusuo Zhang
- CAS and Shandong Province Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, 266071, Qingdao, China.
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, 266237, Qingdao, China.
- Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, 266071, Qingdao, China.
| |
Collapse
|
2
|
Feng M, Gao B, Garcia LR, Sun Q. Microbiota-derived metabolites in regulating the development and physiology of Caenorhabditis elegans. Front Microbiol 2023; 14:1035582. [PMID: 36925470 PMCID: PMC10011103 DOI: 10.3389/fmicb.2023.1035582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 02/09/2023] [Indexed: 03/08/2023] Open
Abstract
Microbiota consist of microorganisms that provide essential health benefits and contribute to the animal's physiological homeostasis. Microbiota-derived metabolites are crucial mediators in regulating host development, system homeostasis, and overall fitness. In this review, by focusing on the animal model Caenorhabditis elegans, we summarize key microbial metabolites and their molecular mechanisms that affect animal development. We also provide, from a bacterial perspective, an overview of host-microbiota interaction networks used for maintaining host physiological homeostasis. Moreover, we discuss applicable methodologies for profiling new bacterial metabolites that modulate host developmental signaling pathways. Microbiota-derived metabolites have the potential to be diagnostic biomarkers for diseases, as well as promising targets for engineering therapeutic interventions against animal developmental or health-related defects.
Collapse
Affiliation(s)
- Min Feng
- Department of Chemical Engineering, Texas A&M University, College Station, TX, United States
| | - Baizhen Gao
- Department of Chemical Engineering, Texas A&M University, College Station, TX, United States
| | - L Rene Garcia
- Department of Biology, Texas A&M University, College Station, TX, United States
| | - Qing Sun
- Department of Chemical Engineering, Texas A&M University, College Station, TX, United States
| |
Collapse
|
3
|
Garcia LR, Garzesi AM, Affonso PHDV, Tonon CR, Felicio ML, Brito FS, Martins AS, Campos NLKL, Okoshi MP, Paiva SAR, Minicucci MF, Polegato BF, Zornoff LAM. Thiamine as an outcome predictor in postoperative CABG patients. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.1244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 11/13/2022] Open
Abstract
Abstract
Introduction
Coronary artery bypass graft surgery (CABG) is one of the most performed cardiovascular procedures worldwide. Despite good outcomes, CABG induces systemic inflammation, increases oxidative stress and increases catabolism. As thiamine act as a cofactor in glucose metabolism and glutathione synthesis, its deficiency could have a high prevalence in critically ill patients.
Purpose
To assess the association between plasma thiamine concentrations and clinical outcomes and 30-day mortality in patients undergoing non-emergency CABG.
Methods
Prospective and observational study that included consecutive patients older than 18 years undergoing CABG that assigned the consent form. Plasma thiamine concentrations were determined before and 24 hours after the procedure by the high-performance liquid chromatography method. The clinical outcomes evaluated were perioperative acute myocardial infarction, heart failure, cardiogenic shock, arrhythmias, stroke and acute kidney injury. Mortality was evaluated on the 30th day after CABG.
Results
The study included 131 patients submitted to CABG. The mean age was 61±9.1 years, 73.3% were men, and the mean EuroScore II value was 1.78±1.3%. Before CABG, plasmatic thiamine concentration was 33±15ng/ml, and 15% of the patients had thiamine deficiency. After CABG, plasmatic thiamine concentration was 20±8ng/ml. All patients diminished plasmatic thiamine concentration after CABG. Mortality was 16% and 24% of patients presented acute kidney injury. Combined outcomes, which included the presence of acute myocardial infarction, heart failure, cardiogenic shock, arrhythmias, stroke, acute kidney injury or death, was present in 52% of the patients. Percentage of thiamine variation between before and after CABG was not associated with mortality (34±14 vs 41±10%; p=0.063); however, it was associated with acute kidney injury (40±14 vs 34±13%; p=0.027) and combined outcomes (37±13 vs 33±14%; p=0.035).
Conclusion
Percentage of thiamine variation from before to after CABG was associated with acute kidney injury and combined outcomes in these patients.
Funding Acknowledgement
Type of funding sources: None.
Collapse
Affiliation(s)
- L R Garcia
- UNESP, Medical School , Botucatu , Brazil
| | | | | | - C R Tonon
- UNESP, Medical School , Botucatu , Brazil
| | | | - F S Brito
- UNESP, Medical School , Botucatu , Brazil
| | | | | | - M P Okoshi
- UNESP, Medical School , Botucatu , Brazil
| | | | | | | | | |
Collapse
|
4
|
Sahu A, Banerjee S, Raju AS, Chiou TJ, Garcia LR, Versaw WK. Spatial Profiles of Phosphate in Roots Indicate Developmental Control of Uptake, Recycling, and Sequestration. Plant Physiol 2020; 184:2064-2077. [PMID: 32999006 PMCID: PMC7723077 DOI: 10.1104/pp.20.01008] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 08/21/2020] [Indexed: 05/07/2023]
Abstract
The availability of inorganic phosphate (Pi) limits plant growth and crop productivity on much of the world's arable land. To better understand how plants cope with deficient and variable supplies of this essential nutrient, we used Pi imaging to spatially resolve and quantify cytosolic Pi concentrations and the respective contributions of Pi uptake, metabolic recycling, and vacuolar sequestration to cytosolic Pi homeostasis in Arabidopsis (Arabidopsis thaliana) roots. Microinjection coupled with confocal microscopy was used to calibrate a FRET-based Pi sensor to determine absolute, rather than relative, Pi concentrations in live plants. High-resolution mapping of cytosolic Pi concentrations in different cells, tissues, and developmental zones of the root revealed that cytosolic concentrations varied between developmental zones, with highest levels in the transition zone, whereas concentrations were equivalent in epidermis, cortex, and endodermis within each zone. Pi concentrations in all zones were reduced, at different rates, by Pi starvation, but the developmental pattern of Pi concentration persisted. Pi uptake, metabolic recycling, and vacuolar sequestration were distinguished in each zone by using cyanide to block Pi assimilation in wild-type plants and a vacuolar Pi transport mutant, and then measuring the subsequent change in cytosolic Pi concentration over time. Each of these processes exhibited distinct spatial profiles in the root, but only vacuolar Pi sequestration corresponded with steady-state cytosolic Pi concentrations. These results highlight the complexity of Pi dynamics in live plants and revealed developmental control of root Pi homeostasis, which has potential implications for plant sensing and signaling of Pi.
Collapse
Affiliation(s)
- Abira Sahu
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Swayoma Banerjee
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | | | - Tzyy-Jen Chiou
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan
| | - L Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Wayne K Versaw
- Department of Biology, Texas A&M University, College Station, Texas 77843
| |
Collapse
|
5
|
Versaw WK, Garcia LR. Intracellular transport and compartmentation of phosphate in plants. Curr Opin Plant Biol 2017; 39:25-30. [PMID: 28570954 DOI: 10.1016/j.pbi.2017.04.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 04/10/2017] [Accepted: 04/16/2017] [Indexed: 05/21/2023]
Abstract
Phosphate (Pi) is an essential macronutrient with structural and metabolic roles within every compartment of the plant cell. Intracellular Pi transporters direct Pi to each organelle and also control its exchange between subcellular compartments thereby providing the means to coordinate compartmented metabolic processes, including glycolysis, photosynthesis, and respiration. In this review we summarize recent advances in the identification and functional analysis of Pi transporters that localize to vacuoles, chloroplasts, non-photosynthetic plastids, mitochondria, and the Golgi apparatus. Electrical potentials across intracellular membranes and the pH of subcellular environments will also be highlighted as key factors influencing the energetics of Pi transport, and therefore pose limits for Pi compartmentation.
Collapse
Affiliation(s)
- Wayne K Versaw
- Texas A&M University, Department of Biology, College Station, TX 77843, USA.
| | - L Rene Garcia
- Texas A&M University, Department of Biology, College Station, TX 77843, USA
| |
Collapse
|
6
|
Serrano-Saiz E, Pereira L, Gendrel M, Aghayeva U, Bhattacharya A, Howell K, Garcia LR, Hobert O. A Neurotransmitter Atlas of the Caenorhabditis elegans Male Nervous System Reveals Sexually Dimorphic Neurotransmitter Usage. Genetics 2017; 206:1251-1269. [PMID: 28684604 PMCID: PMC5500128 DOI: 10.1534/genetics.117.202127] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 05/03/2017] [Indexed: 11/18/2022] Open
Abstract
The nervous system of most animals is sexually dimorphic but such dimorphisms are generally poorly mapped on an anatomical, cellular, and molecular level. The adult nervous system of the nematode Caenorhabditis elegans displays a number of clearly defined anatomical sexual dimorphisms, but molecular features of sexually dimorphic neurons remain sparse. In this resource paper, we provide a comprehensive atlas of neurotransmitters used in the nervous system of the male and compare it to that of the hermaphrodite. Among the three major neurotransmitter systems, acetylcholine (ACh) is the most frequently used, followed by glutamate (Glu), and lastly γ-aminobutyric acid (GABA). Many male-specific neurons utilize multiple neurotransmitter systems. Interestingly, we find that neurons that are present in both sexes alter their neurotransmitter usage depending on the sex of the animal. One neuron scales up its usage of ACh, another becomes serotonergic in males, and another one adds a new neurotransmitter (glutamate) to its nonsex-specific transmitter (ACh). In all these cases, neurotransmitter changes are correlated with substantial changes in synaptic connectivity. We assembled the neurotransmitter maps of the male-specific nervous system into a comprehensive atlas that describes the anatomical position of all the neurons of the male-specific nervous system relative to the sex-shared nervous system. We exemplify the usefulness of the neurotransmitter atlas by using it as a tool to define the expression pattern of a synaptic organizer molecule in the male tail. Taken together, the male neurotransmitter atlas provides an entry point for future functional and developmental analysis of the male nervous system.
Collapse
Affiliation(s)
- Esther Serrano-Saiz
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| | - Laura Pereira
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| | - Marie Gendrel
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| | - Ulkar Aghayeva
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| | - Abhishek Bhattacharya
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| | - Kelly Howell
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| | - L Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Oliver Hobert
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York 10027
| |
Collapse
|
7
|
Jee C, Goncalves JF, LeBoeuf B, Garcia LR. CRF-like receptor SEB-3 in sex-common interneurons potentiates stress handling and reproductive drive in C. elegans. Nat Commun 2016; 7:11957. [PMID: 27321013 PMCID: PMC4915151 DOI: 10.1038/ncomms11957] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [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] [Received: 10/28/2015] [Accepted: 05/13/2016] [Indexed: 02/08/2023] Open
Abstract
Environmental conditions can modulate innate behaviours. Although male Caenorhabditis elegans copulation can be perturbed in the presence of stress, the mechanisms underlying its decision to sustain copulation are unclear. Here we describe a mating interference assay, which quantifies the persistence of male C. elegans copulation in noxious blue light. We show that between copulations, the male escapes from blue light illumination at intensities over 370 μW mm−2. This response is attenuated in mutants with constitutive activation of the corticotropin-releasing factor receptor family homologue SEB-3. We show that activation of this receptor causes sex-common glutamatergic lumbar ganglion interneurons (LUA) to potentiate downstream male-specific reproduction circuits, allowing copulatory behaviours to partially override the light-induced escape responses in the male. SEB-3 activation in LUA also potentiates copulation during mild starvation. We suggest that SEB-3 activation allows C. elegans to acclimate to the environment and thus continue to execute innate behaviours even under non-optimal conditions. Innate animal behaviours can be negatively regulated by environmental stressors. Jee et al. show that suppression of male C. elegans copulation behaviour by noxious light can be overcome by activation of SEB-3, a homologue of the stress-associated mammalian corticotropin-releasing factor receptor family.
Collapse
Affiliation(s)
- Changhoon Jee
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU, College Station, Texas 77843-3258, USA
| | - Jimmy F Goncalves
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU, College Station, Texas 77843-3258, USA
| | - Brigitte LeBoeuf
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU, College Station, Texas 77843-3258, USA
| | - L Rene Garcia
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU, College Station, Texas 77843-3258, USA
| |
Collapse
|
8
|
Rosas PC, Nagaraja GM, Kaur P, Panossian A, Wickman G, Garcia LR, Al-Khamis FA, Asea AAA. Hsp72 (HSPA1A) Prevents Human Islet Amyloid Polypeptide Aggregation and Toxicity: A New Approach for Type 2 Diabetes Treatment. PLoS One 2016; 11:e0149409. [PMID: 26960140 PMCID: PMC4784952 DOI: 10.1371/journal.pone.0149409] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 02/01/2016] [Indexed: 12/30/2022] Open
Abstract
Type 2 diabetes is a growing public health concern and accounts for approximately 90% of all the cases of diabetes. Besides insulin resistance, type 2 diabetes is characterized by a deficit in β-cell mass as a result of misfolded human islet amyloid polypeptide (h-IAPP) which forms toxic aggregates that destroy pancreatic β-cells. Heat shock proteins (HSP) play an important role in combating the unwanted self-association of unfolded proteins. We hypothesized that Hsp72 (HSPA1A) prevents h-IAPP aggregation and toxicity. In this study, we demonstrated that thermal stress significantly up-regulates the intracellular expression of Hsp72, and prevents h-IAPP toxicity against pancreatic β-cells. Moreover, Hsp72 (HSPA1A) overexpression in pancreatic β-cells ameliorates h-IAPP toxicity. To test the hypothesis that Hsp72 (HSPA1A) prevents aggregation and fibril formation, we established a novel C. elegans model that expresses the highly amyloidogenic human pro-IAPP (h-proIAPP) that is implicated in amyloid formation and β-cell toxicity. We demonstrated that h-proIAPP expression in body-wall muscles, pharynx and neurons adversely affects C. elegans development. In addition, we demonstrated that h-proIAPP forms insoluble aggregates and that the co-expression of h-Hsp72 in our h-proIAPP C. elegans model, increases h-proIAPP solubility. Furthermore, treatment of transgenic h-proIAPP C. elegans with ADAPT-232, known to induce the expression and release of Hsp72 (HSPA1A), significantly improved the growth retardation phenotype of transgenic worms. Taken together, this study identifies Hsp72 (HSPA1A) as a potential treatment to prevent β-cell mass decline in type 2 diabetic patients and establishes for the first time a novel in vivo model that can be used to select compounds that attenuate h-proIAPP aggregation and toxicity.
Collapse
Affiliation(s)
- Paola C. Rosas
- Division of Investigative Pathology, Scott & White Hospital and the Texas A&M Health Science Center, College of Medicine, Temple, Texas, United States of America
| | - Ganachari M. Nagaraja
- Division of Investigative Pathology, Scott & White Hospital and the Texas A&M Health Science Center, College of Medicine, Temple, Texas, United States of America
| | - Punit Kaur
- Department of Microbiology, Biochemistry & Immunology, Morehouse School of Medicine, Atlanta, Georgia, United States of America
- University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | | | - Georg Wickman
- Department of Research, Swedish Herbal Institute, Åskloster, Sweden
| | - L. Rene Garcia
- Department of Biology and Howard Hughes Medical Institute, Texas A&M University, College Station, Texas, United States of America
| | - Fahd A. Al-Khamis
- Department for Neuroscience Research, Institutes for Research & Medical Consultancies (IRMC) and Deanship for Scientific Research, University of Dammam, Dammam, Saudi Arabia
| | - Alexzander A. A. Asea
- Department for Neuroscience Research, Institutes for Research & Medical Consultancies (IRMC) and Deanship for Scientific Research, University of Dammam, Dammam, Saudi Arabia
- * E-mail:
| |
Collapse
|
9
|
Pereira L, Kratsios P, Serrano-Saiz E, Sheftel H, Mayo AE, Hall DH, White JG, LeBoeuf B, Garcia LR, Alon U, Hobert O. A cellular and regulatory map of the cholinergic nervous system of C. elegans. eLife 2015; 4. [PMID: 26705699 PMCID: PMC4769160 DOI: 10.7554/elife.12432] [Citation(s) in RCA: 179] [Impact Index Per Article: 19.9] [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: 10/20/2015] [Accepted: 12/22/2015] [Indexed: 12/18/2022] Open
Abstract
Nervous system maps are of critical importance for understanding how nervous systems develop and function. We systematically map here all cholinergic neuron types in the male and hermaphrodite C. elegans nervous system. We find that acetylcholine (ACh) is the most broadly used neurotransmitter and we analyze its usage relative to other neurotransmitters within the context of the entire connectome and within specific network motifs embedded in the connectome. We reveal several dynamic aspects of cholinergic neurotransmitter identity, including a sexually dimorphic glutamatergic to cholinergic neurotransmitter switch in a sex-shared interneuron. An expression pattern analysis of ACh-gated anion channels furthermore suggests that ACh may also operate very broadly as an inhibitory neurotransmitter. As a first application of this comprehensive neurotransmitter map, we identify transcriptional regulatory mechanisms that control cholinergic neurotransmitter identity and cholinergic circuit assembly. DOI:http://dx.doi.org/10.7554/eLife.12432.001 To better understand the nervous system—the most complex of all the body’s organs—scientists have begun to painstakingly map its many features. These maps can then be used as a basis for understanding how the nervous system develops and works. Researchers have mapped the connections – called synapses – between all the nerve cells in the nervous system of a simple worm called Caenorhabditis elegans. Cells communicate by releasing chemicals called neurotransmitters across the synapses, but it is not fully known which types of neurotransmitters are released across each of the synapses in C. elegans. Now, Pereira et al. have mapped all worm nerve cells that use a neurotransmitter called acetylcholine by fluorescently marking proteins that synthesize and transport the neurotransmitter. This map revealed that 52 of the 118 types of nerve cells in the worm use acetylcholine, making it the most widely used neurotransmitter. This information was then combined with the findings of previous work that investigated which nerve cells release some other types of neurotransmitters. The combined data mean that it is now known which neurotransmitter is used for signaling by over 90% of the nerve cells in C. elegans. Using the map, Pereira et al. found that some neurons release different neurotransmitters in the different sexes of the worm. Additionally, the experiments revealed a set of proteins that cause the nerve cells to produce acetylcholine. Some of these proteins affect the fates of connected nerve cells. Overall, this information will allow scientists to more precisely manipulate specific cells or groups of cells in the worm nervous system to investigate how the nervous system develops and is regulated. DOI:http://dx.doi.org/10.7554/eLife.12432.002
Collapse
Affiliation(s)
- Laura Pereira
- Department of Biological Sciences, Columbia University, New York, United States.,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Paschalis Kratsios
- Department of Biological Sciences, Columbia University, New York, United States.,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Esther Serrano-Saiz
- Department of Biological Sciences, Columbia University, New York, United States.,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Hila Sheftel
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Avi E Mayo
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - David H Hall
- Department of Neuroscience, Albert Einstein College of Medicine, New York, United States
| | - John G White
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Brigitte LeBoeuf
- Department of Biology, Texas A&M University, College Station, United States
| | - L Rene Garcia
- Department of Biology, Texas A&M University, College Station, United States.,Howard Hughes Medical Institute, Texas A&M University, College Station, United States
| | - Uri Alon
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Oliver Hobert
- Department of Biological Sciences, Columbia University, New York, United States.,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, United States.,Howard Hughes Medical Institute, Columbia University, New York, United States
| |
Collapse
|
10
|
Banerjee S, Versaw WK, Garcia LR. Imaging Cellular Inorganic Phosphate in Caenorhabditis elegans Using a Genetically Encoded FRET-Based Biosensor. PLoS One 2015; 10:e0141128. [PMID: 26484766 PMCID: PMC4615621 DOI: 10.1371/journal.pone.0141128] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [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: 08/21/2015] [Accepted: 10/05/2015] [Indexed: 01/02/2023] Open
Abstract
Inorganic phosphate (Pi) has central roles in metabolism, cell signaling and energy conversion. The distribution of Pi to each cell and cellular compartment of an animal must be tightly coordinated with its dietary supply and with the varied metabolic demands of individual cells. An analytical method for monitoring Pi dynamics with spatial and temporal resolution is therefore needed to gain a comprehensive understanding of mechanisms governing the transport and recycling of this essential nutrient. Here we demonstrate the utility of a genetically encoded FRET-based Pi sensor to assess cellular Pi levels in the nematode Caenorhabditis elegans. The sensor was expressed in different cells and tissues of the animal, including head neurons, tail neurons, pharyngeal muscle, and the intestine. Cytosolic Pi concentrations were monitored using ratiometric imaging. Injection of phosphate buffer into intestinal cells confirmed that the sensor was responsive to changes in Pi concentration in vivo. Live Pi imaging revealed cell-specific and developmental stage-specific differences in cytosolic Pi concentrations. In addition, cellular Pi levels were perturbed by food deprivation and by exposure to the respiratory inhibitor cyanide. These results suggest that Pi concentration is a sensitive indicator of metabolic status. Moreover, we propose that live Pi imaging in C. elegans is a powerful approach to discern mechanisms that govern Pi distribution in individual cells and throughout an animal.
Collapse
Affiliation(s)
- Swayoma Banerjee
- Department of Biology, Texas A&M University, 3258 TAMU, College Station, TX, 77843-3258, United States of America
| | - Wayne K. Versaw
- Department of Biology, Texas A&M University, 3258 TAMU, College Station, TX, 77843-3258, United States of America
| | - L. Rene Garcia
- Department of Biology, Texas A&M University, 3258 TAMU, College Station, TX, 77843-3258, United States of America
- Howard Hughes Medical Institute, College Station, TX, 77843-3258, United States of America
- * E-mail:
| |
Collapse
|
11
|
Mukherjee P, Banerjee S, Wheeler A, Ratliff LA, Irigoyen S, Garcia LR, Lockless SW, Versaw WK. Live imaging of inorganic phosphate in plants with cellular and subcellular resolution. Plant Physiol 2015; 167:628-38. [PMID: 25624397 PMCID: PMC4348774 DOI: 10.1104/pp.114.254003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 01/25/2015] [Indexed: 05/17/2023]
Abstract
Despite variable and often scarce supplies of inorganic phosphate (Pi) from soils, plants must distribute appropriate amounts of Pi to each cell and subcellular compartment to sustain essential metabolic activities. The ability to monitor Pi dynamics with subcellular resolution in live plants is, therefore, critical for understanding how this essential nutrient is acquired, mobilized, recycled, and stored. Fluorescence indicator protein for inorganic phosphate (FLIPPi) sensors are genetically encoded fluorescence resonance energy transfer-based sensors that have been used to monitor Pi dynamics in cultured animal cells. Here, we present a series of Pi sensors optimized for use in plants. Substitution of the enhanced yellow fluorescent protein component of a FLIPPi sensor with a circularly permuted version of Venus enhanced sensor dynamic range nearly 2.5-fold. The resulting circularly permuted FLIPPi sensor was subjected to a high-efficiency mutagenesis strategy that relied on statistical coupling analysis to identify regions of the protein likely to influence Pi affinity. A series of affinity mutants was selected with dissociation constant values of 0.08 to 11 mm, which span the range for most plant cell compartments. The sensors were expressed in Arabidopsis (Arabidopsis thaliana), and ratiometric imaging was used to monitor cytosolic Pi dynamics in root cells in response to Pi deprivation and resupply. Moreover, plastid-targeted versions of the sensors expressed in the wild type and a mutant lacking the PHOSPHATE TRANSPORT4;2 plastidic Pi transporter confirmed a physiological role for this transporter in Pi export from root plastids. These circularly permuted FLIPPi sensors, therefore, enable detailed analysis of Pi dynamics with subcellular resolution in live plants.
Collapse
Affiliation(s)
- Pallavi Mukherjee
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Swayoma Banerjee
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Amanda Wheeler
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Lyndsay A Ratliff
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Sonia Irigoyen
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - L Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Steve W Lockless
- Department of Biology, Texas A&M University, College Station, Texas 77843
| | - Wayne K Versaw
- Department of Biology, Texas A&M University, College Station, Texas 77843
| |
Collapse
|
12
|
Zhang L, Gualberto DG, Guo X, Correa P, Jee C, Garcia LR. TMC-1 attenuates C. elegans development and sexual behaviour in a chemically defined food environment. Nat Commun 2015; 6:6345. [PMID: 25695879 DOI: 10.1038/ncomms7345] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 01/21/2015] [Indexed: 01/22/2023] Open
Abstract
Although diet affects growth and behaviour, the adaptive mechanisms that coordinate these processes in non-optimal food sources are unclear. Here we show that the C. elegans tmc-1 channel, which is homologous to the mammalian tmc deafness genes, attenuates development and inhibits sexual behaviour in non-optimal food, the synthetic CeMM medium. In CeMM medium, signalling from the pharyngeal MC neurons and body wall muscles slows larval development. However, in the non-standard diet, mutation in tmc-1 accelerates development, by impairing the excitability of these cells. The tmc-1 larva can immediately generate ATP when fed CeMM, and their fast development requires insulin signalling. Our findings suggest that the tmc-1 channel indirectly affects metabolism in wild-type animals. In addition to regulating the development, we show that mutating tmc-1 can relax diet-induced inhibition of male sexual behaviour, thus indicating that a single regulator can be genetically modified to promote growth rate and reproductive success in new environments.
Collapse
Affiliation(s)
- Liusuo Zhang
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU College Station, Texas 77843-3258, USA
| | - Daisy G Gualberto
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU College Station, Texas 77843-3258, USA
| | - Xiaoyan Guo
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU College Station, Texas 77843-3258, USA
| | - Paola Correa
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU College Station, Texas 77843-3258, USA
| | - Changhoon Jee
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU College Station, Texas 77843-3258, USA
| | - L Rene Garcia
- Department of Biology, Howard Hughes Medical Institute, Texas A&M University, 3258 TAMU College Station, Texas 77843-3258, USA
| |
Collapse
|
13
|
Liu Y, LeBeouf B, Guo X, Correa PA, Gualberto DG, Lints R, Garcia LR. A cholinergic-regulated circuit coordinates the maintenance and bi-stable states of a sensory-motor behavior during Caenorhabditis elegans male copulation. PLoS Genet 2011; 7:e1001326. [PMID: 21423722 PMCID: PMC3053324 DOI: 10.1371/journal.pgen.1001326] [Citation(s) in RCA: 34] [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: 07/06/2010] [Accepted: 02/04/2011] [Indexed: 11/18/2022] Open
Abstract
Penetration of a male copulatory organ into a suitable mate is a conserved and necessary behavioral step for most terrestrial matings; however, the detailed molecular and cellular mechanisms for this distinct social interaction have not been elucidated in any animal. During mating, the Caenorhabditis elegans male cloaca is maintained over the hermaphrodite's vulva as he attempts to insert his copulatory spicules. Rhythmic spicule thrusts cease when insertion is sensed. Circuit components consisting of sensory/motor neurons and sex muscles for these steps have been previously identified, but it was unclear how their outputs are integrated to generate a coordinated behavior pattern. Here, we show that cholinergic signaling between the cloacal sensory/motor neurons and the posterior sex muscles sustains genital contact between the sexes. Simultaneously, via gap junctions, signaling from these muscles is transmitted to the spicule muscles, thus coupling repeated spicule thrusts with vulval contact. To transit from rhythmic to sustained muscle contraction during penetration, the SPC sensory-motor neurons integrate the signal of spicule's position in the vulva with inputs from the hook and cloacal sensilla. The UNC-103 K(+) channel maintains a high excitability threshold in the circuit, so that sustained spicule muscle contraction is not stimulated by fewer inputs. We demonstrate that coordination of sensory inputs and motor outputs used to initiate, maintain, self-monitor, and complete an innate behavior is accomplished via the coupling of a few circuit components.
Collapse
Affiliation(s)
- Yishi Liu
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Brigitte LeBeouf
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Howard Hughes Medical Institute, Texas A&M University, College Station, Texas, United States of America
| | - Xiaoyan Guo
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Paola A. Correa
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Daisy G. Gualberto
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Howard Hughes Medical Institute, Texas A&M University, College Station, Texas, United States of America
| | - Robyn Lints
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - L. Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
- Howard Hughes Medical Institute, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
| |
Collapse
|
14
|
Gruninger TR, Gualberto DG, Garcia LR. Sensory perception of food and insulin-like signals influence seizure susceptibility. PLoS Genet 2008; 4:e1000117. [PMID: 18604269 PMCID: PMC2432499 DOI: 10.1371/journal.pgen.1000117] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [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: 03/25/2008] [Accepted: 06/04/2008] [Indexed: 11/18/2022] Open
Abstract
Food deprivation is known to affect physiology and behavior. Changes that occur could be the result of the organism's monitoring of internal and external nutrient availability. In C. elegans, male mating is dependent on food availability; food-deprived males mate with lower efficiency compared to their well-fed counterparts, suggesting that the mating circuit is repressed in low-food environments. This behavioral response could be mediated by sensory neurons exposed to the environment or by internal metabolic cues. We demonstrated that food-deprivation negatively regulates sex-muscle excitability through the activity of chemosensory neurons and insulin-like signaling. Specifically, we found that the repressive effects of food deprivation on the mating circuit can be partially blocked by placing males on inedible food, E. coli that can be sensed but not eaten. We determined that the olfactory AWC neurons actively suppress sex-muscle excitability in response to food deprivation. In addition, we demonstrated that loss of insulin-like receptor (DAF-2) signaling in the sex muscles blocks the ability of food deprivation to suppress the mating circuit. During low-food conditions, we propose that increased activity by specific olfactory neurons (AWCs) leads to the release of neuroendocrine signals, including insulin-like ligands. Insulin-like receptor signaling in the sex muscles then reduces cell excitability via activation of downstream molecules, including PLC-gamma and CaMKII.
Collapse
Affiliation(s)
- Todd R. Gruninger
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - Daisy G. Gualberto
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| | - L. Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas, United States of America
| |
Collapse
|
15
|
Reiner DJ, Weinshenker D, Tian H, Thomas JH, Nishiwaki K, Miwa J, Gruninger T, Leboeuf B, Garcia LR. Behavioral genetics of caenorhabditis elegans unc-103-encoded erg-like K(+) channel. J Neurogenet 2007; 20:41-66. [PMID: 16807195 DOI: 10.1080/01677060600788826] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The Caenorhabditis elegans unc-103 gene encodes a potassium channel whose sequence is most similar to the ether-a-go-go related gene (erg) type of K+ channels. We find that the n 500 and e 1597 gain-of-function (gf) mutations in unc-103 cause reduced excitation in most muscles, while loss-of-function (lf) mutations cause mild muscle hyper-excitability. Both gf alleles change the same residue near the cytoplasmic end of S6, consistent with this region regulating channel activation. We also report additional dominant-negative and lf alleles of unc-103 that can antagonize or reduce the function of both gf and wild-type alleles. The unc-103 locus contains 6 promoter regions that express unc-103 in different combinations of body-wall and sex-specific muscles, motor-, inter- and sensory-neurons. Each promoter drives transcripts containing a unique first exon, conferring sequence variability to the N-terminus of the UNC-103 protein, while three splice variants introduce variability into the UNC-103 C-terminus. unc-103(0) hermaphrodites prematurely lay embryos that would normally be retained in the uterus and lay eggs under conditions that inhibit egg-laying behavior. In the egg-laying circuit, unc-103 is expressed in vulval muscles and the HSN neurons from different promoters. Supplying the proper UNC-103 isoform to the vulval muscles is sufficient to restore regulation to egg-laying behavior.
Collapse
Affiliation(s)
- David J Reiner
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Abstract
In this study, we addressed why Caenorhabditis elegans males are inefficient at fertilizing their hermaphrodites. During copulation, hermaphrodites generally move away from males before they become impregnated. C. elegans hermaphrodites reproduce by internal self-fertilization, so that copulation with males is not required for species propagation. The hermaphroditic mode of reproduction could potentially relax selection for genes that optimize male mating behavior. We examined males from hermaphroditic and gonochoristic (male-female copulation) Caenorhabditis species to determine if they use different sensory and motor mechanisms to control their mating behavior. Instead, we found through laser ablation analysis and behavioral observations that hermaphroditic C. briggsae and gonochoristic C. remanei and Caenorhabditis species 4, PB2801 males produce a factor that immobilizes females during copulation. This factor also stimulates the vulval slit to widen, so that the male copulatory spicules can easily insert. C. elegans and C. briggsae hermaphrodites are not affected by this factor. We suggest that sensory and motor execution of mating behavior have not significantly changed among males of different Caenorhabditis species; however, during the evolution of internal self-fertilization, hermaphrodites have lost the ability to respond to the male soporific-inducing factor.
Collapse
Affiliation(s)
- L Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas 77843-3258, USA.
| | | | | |
Collapse
|
17
|
Gruninger TR, LeBoeuf B, Liu Y, Garcia LR. Molecular signaling involved in regulating feeding and other mitivated behaviors. Mol Neurobiol 2007; 35:1-20. [PMID: 17519503 DOI: 10.1007/bf02700621] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 11/30/1999] [Accepted: 09/06/2006] [Indexed: 12/29/2022]
Abstract
The metabolic and nutritional status of an organism influences multiple behaviors in addition to food intake. When an organism is hungry, it employs behaviors that help it locate and ingest food while suppressing behaviors that are not associated with this goal. Alternatively, when an organism is satiated, food-seeking behaviors are repressed so that the animal can direct itself to other goal-oriented tasks such as reproductive behaviors. Studies in both vertebrate and invertebrate model systems have revealed that food-deprived and -satiated behaviors are differentially executed and integrated via common molecular signaling mechanisms. This article discusses cellular and molecular mechanisms for how insulin, neuropeptide Y (NPY), and serotonin utilize common signaling pathways to integrate feeding and metabolic state with other motivated behaviors. Insulin, NPY, and serotonin are three of the most well-studied molecules implicated in regulating such behaviors. Overall, insulin signaling allows an organism to coordinate proper behavioral output with changes in metabolism, NPY activates behaviors required for locating and ingesting food, and serotonin modulates behaviors performed when an organism is satiated. These three molecules work to ensure that the proper behaviors are executed in response to the feeding state of an organism.
Collapse
Affiliation(s)
- Todd R Gruninger
- Department of Biology, Texas A&M University, TAMU 3258, College Station, TX, USA
| | | | | | | |
Collapse
|
18
|
Abstract
Caenorhabditis elegans male mating provides an excellent opportunity to determine how sensory perception regulates behavior and motor programs. The male-specific nervous system and muscles are superimposed over the general nervous system and musculature. Genetic screens and genomic approaches have identified male-specific and male-enriched genes as well as non-sex specific molecules specialized for mating sub-behaviors. In this chapter, we discuss the cellular, genetic, and molecular basis for male mating behavior.
Collapse
Affiliation(s)
- Maureen M Barr
- School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA.
| | | |
Collapse
|
19
|
Gruninger TR, Gualberto DG, LeBoeuf B, Garcia LR. Integration of male mating and feeding behaviors in Caenorhabditis elegans. J Neurosci 2006; 26:169-79. [PMID: 16399684 PMCID: PMC6674329 DOI: 10.1523/jneurosci.3364-05.2006] [Citation(s) in RCA: 41] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Revised: 11/07/2005] [Accepted: 11/07/2005] [Indexed: 11/21/2022] Open
Abstract
The Caenorhabditis elegans male must integrate various environmental cues to ensure proper execution of mating. One step of male mating, the insertion of the male copulatory spicules into its mate, requires UNC-103 ERG (ether-a-go-go-related gene)-like K+ channels. unc-103(lf) alleles cause males to protract their spicules spontaneously in the absence of mating cues. To identify proteins that work with UNC-103, we suppressed unc-103(lf) and isolated lev-11(rg1). LEV-11 (tropomyosin) regulates the spicules directly by controlling the male sex muscles and indirectly by controlling the pharyngeal muscles. lev-11-mediated suppression requires the pharyngeal NSM neurosecretory motor neurons; ablating these neurons in lev-11(rg1); unc-103(lf) males restores spontaneous spicule protraction. Additionally, unc-103-induced spicule protraction can be suppressed by reducing a pharyngeal-specific troponin T. These observations demonstrate that non-genitalia cells involved in feeding also mediate male sexual behaviors.
Collapse
Affiliation(s)
- Todd R Gruninger
- Department of Biology, Texas A&M University, College Station, Texas 77843-3258, USA
| | | | | | | |
Collapse
|
20
|
Moghal N, Garcia LR, Khan LA, Iwasaki K, Sternberg PW. Modulation of EGF receptor-mediated vulva development by the heterotrimeric G-protein Galphaq and excitable cells in C. elegans. Development 2003; 130:4553-66. [PMID: 12925583 DOI: 10.1242/dev.00670] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The extent to which excitable cells and behavior modulate animal development has not been examined in detail. Here, we demonstrate the existence of a novel pathway for promoting vulval fates in C. elegans that involves activation of the heterotrimeric Galphaq protein, EGL-30. EGL-30 acts with muscle-expressed EGL-19 L-type voltage-gated calcium channels to promote vulva development, and acts downstream or parallel to LET-60 (RAS). This pathway is not essential for vulval induction on standard Petri plates, but can be stimulated by expression of activated EGL-30 in neurons, or by an EGL-30-dependent change in behavior that occurs in a liquid environment. Our results indicate that excitable cells and animal behavior can provide modulatory inputs into the effects of growth factor signaling on cell fates, and suggest that communication between these cell populations is important for normal development to occur under certain environmental conditions.
Collapse
Affiliation(s)
- Nadeem Moghal
- Howard Hughes Medical Institute and Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA.
| | | | | | | | | |
Collapse
|
21
|
Garcia LR, Sternberg PW. Caenorhabditis elegans UNC-103 ERG-like potassium channel regulates contractile behaviors of sex muscles in males before and during mating. J Neurosci 2003; 23:2696-705. [PMID: 12684455 PMCID: PMC6742059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2002] [Revised: 01/09/2003] [Accepted: 01/13/2003] [Indexed: 03/01/2023] Open
Abstract
During mating behavior the Caenorhabditis elegans male must regulate periodic and prolonged protractor muscle contractions to insert his copulatory spicules into his mate. The protractors undergo periodic contractions to allow the spicules to reattempt insertion if a previous thrust failed to breach the vulva. When the spicule tips penetrate the vulva, the protractors undergo prolonged contraction to keep the spicules inside the hermaphrodite until sperm transfer is complete. To understand how these contractions are regulated, we isolated EMS-induced mutations that cause males to execute prolonged contraction inappropriately. Loss-of-function mutations in the unc-103 ERG-like K(+) channel gene cause the protractor muscles to contract in the absence of mating stimulation. unc-103-induced spicule protraction can be suppressed by killing the SPC motor neurons and the anal depressor muscle: cells that directly contact the protractors. Also, reduction in acetylcholine suppresses unc-103-induced protraction, suggesting that UNC-103 keeps cholinergic neurons from stimulating the protractors before mating behavior. UNC-103 also regulates the timing of spicule protraction during mating behavior. unc-103 males that do not display mating-independent spicule protraction show abnormal spicule insertion behavior during sex. In contrast to wild-type males, unc-103 mutants execute prolonged contractions spontaneously within sequences of periodic protractor contractions. The premature prolonged contractions cause the spicules to extend from the male tail before the spicule tips penetrate the vulva. These observations demonstrate that unc-103 controls various aspects of spicule function.
Collapse
Affiliation(s)
- L Rene Garcia
- Department of Biology, Texas A&M University, College Station, Texas 77843-3258, USA.
| | | |
Collapse
|
22
|
Abstract
We demonstrate through cell ablation, molecular genetic, and pharmacological approaches that during C. elegans male mating behavior, the male inserts his copulatory spicules into the hermaphrodite by regulating periodic and prolonged spicule muscle contractions. Distinct cholinergic neurons use different ACh receptors and calcium channels in the spicule muscles to mediate these contractile behaviors. The PCB and PCC sensory neurons facilitate periodic contraction through muscle-encoded UNC-68 ryanodine receptor calcium channels. The SPC motor neurons trigger prolonged contraction through EGL-19 L-type voltage-gated calcium channels. The male gonad then lengthens the duration of EGL-19-mediated prolonged muscle contraction. This regulation of muscle contraction provides a paradigm to explain how animals initiate, monitor, and maintain a behavioral motor program.
Collapse
Affiliation(s)
- L R Garcia
- Howard Hughes Medical Institute, Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
| | | | | |
Collapse
|
23
|
Fukasawa LO, Gorla MC, Schenkman RP, Garcia LR, Carneiro SM, Raw I, Tanizaki MM. Neisseria meningitidis serogroup C polysaccharide and serogroup B outer membrane vesicle conjugate as a bivalent meningococcus vaccine candidate. Vaccine 1999; 17:2951-8. [PMID: 10462229 DOI: 10.1016/s0264-410x(99)00177-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [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: 10/17/2022]
Abstract
Neisseria meningitidis serogroup C polysaccharide (PS C) was conjugated to serogroup B outer membrane vesicles (OMV) in order to test the possibility of obtaining a bivalent group B and C meningococcus vaccine. The conjugate and controls were injected intraperitoneally into groups of ten mice with boosters on days 14 and 28 after the primary immunization. The following groups were used as control: (i) PS C; (ii) PS C plus OMV; (iii) OMV; and (iv) saline. The serum collected on days 0, 14, 28 and 42 were tested by enzyme-linked immunosorbent assay (ELISA) for PS C and OMV, and by complement mediated bactericidal assay against serogroups B and C. ELISA for PS C as well as bactericidal titres against serogroup C meningococci of the conjugated vaccine increased eight-fold (ELISA) and 32 fold (bactericidal) after 42 days in comparison with the PS C control group. ELISA for OMV and bactericidal titre against serogroup B meningococci of the conjugate showed no significant difference in comparison with the OMV containing controls. Furthermore, Western Blot assay of the conjugate immune serum did not bind OMV class four protein which is related to the complement dependent antibody suppressor. The results indicate that the PS C-OMV conjugate could be a candidate for a bivalent vaccine toward serogroups B and C meningococci.
Collapse
Affiliation(s)
- L O Fukasawa
- Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil
| | | | | | | | | | | | | |
Collapse
|
24
|
Garcia LR. Letter: Michigan P.A.s. J Leg Med (N Y) 1976; 4:suppl 13-4. [PMID: 6602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
25
|
Geslani FT, Base-Habaradas CA, Garcia LR. Surgical management of primary hyperthyroidism. Philipp J Surg Surg Spec 1966; 21:322-5. [PMID: 4166996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|