1
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Yu Z, Wang Z, Liu L. Electrophysiological techniques in marine microalgae study: A new perspective for harmful algal bloom (HAB) research. HARMFUL ALGAE 2024; 134:102629. [PMID: 38705615 DOI: 10.1016/j.hal.2024.102629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 04/11/2024] [Accepted: 04/15/2024] [Indexed: 05/07/2024]
Abstract
Electrophysiological techniques, by measuring bioelectrical signals and ion channel activities in tissues and cells, are now widely utilized to study ion channel-related physiological functions and their underlying mechanisms. Electrophysiological techniques have been extensively employed in the investigation of animals, plants, and microorganisms; however, their application in marine algae lags behind that in other organisms. In this paper, we present an overview of current electrophysiological techniques applicable to algae while reviewing the historical usage of such techniques in this field. Furthermore, we explore the potential specific applications of electrophysiological technology in harmful algal bloom (HAB) research. The application prospects in the studies of stress tolerance, competitive advantage, nutrient absorption, toxin synthesis and secretion by HAB microalgae are discussed and anticipated herein with the aim of providing novel perspectives on HAB investigations.
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Affiliation(s)
- Zhiming Yu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Laboratory of Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, 266071, China.
| | - Zhongshi Wang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Laboratory of Marine Ecology and Environmental Science, Laoshan Laboratory, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, 266071, China
| | - Lidong Liu
- The Djavad Mowafaghian Centre for Brian Health and Department of Medicine, University of British Columbia, Vancouver, BC, Canada
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2
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Raposo-Garcia S, Costas C, Louzao MC, Vieytes MR, Vale C, Botana LM. Synergistic Effect of Brevetoxin BTX-3 and Ciguatoxin CTX3C in Human Voltage-Gated Na v1.6 Sodium Channels. Chem Res Toxicol 2023; 36:1990-2000. [PMID: 37965843 PMCID: PMC10845145 DOI: 10.1021/acs.chemrestox.3c00267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 11/02/2023] [Accepted: 11/06/2023] [Indexed: 11/16/2023]
Abstract
Emerging marine biotoxins such as ciguatoxins and brevetoxins have been widely and independently studied as food pollutants. Their maximum levels in food components were set without considering their possible synergistic effects as consequence of their coexistence in seafood and their action at the same cellular target. The absolute lack of data and regulations of the possible combined effects that both marine biotoxins may have raised the need to analyze their direct in vitro effects using electrophysiology techniques. The results presented in this study indicate that ciguatoxins and brevetoxins had a synergistic effect on human Nav1.6 voltage-gated sodium channels by hyperpolarizing their activation and inactivation states. The results presented here indicate that brevetoxin 3 (BTX-3) acts as partial agonist of human sodium channels, while ciguatoxin 3C (CTX3C) was a full agonist, explaining the differences in the effect of each toxin in the channel. Therefore, this work sets the cellular basis to further apply this type of studies to other food toxicants that may act synergistically and thus implement the corresponding regulatory limits considering their coexistence and the risks to human and animal health derived from it.
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Affiliation(s)
- Sandra Raposo-Garcia
- Departamento
de Farmacología, Farmacia y Tecnología Farmacéutica,
Facultad de Veterinaria, IDIS, Universidad
de Santiago de Compostela, Campus Universitario s/n, Lugo 27002, Spain
| | - Celia Costas
- Departamento
de Farmacología, Farmacia y Tecnología Farmacéutica,
Facultad de Veterinaria, IDIS, Universidad
de Santiago de Compostela, Campus Universitario s/n, Lugo 27002, Spain
| | - M. Carmen Louzao
- Departamento
de Farmacología, Farmacia y Tecnología Farmacéutica,
Facultad de Veterinaria, IDIS, Universidad
de Santiago de Compostela, Campus Universitario s/n, Lugo 27002, Spain
| | - Mercedes R. Vieytes
- Departamento
de Fisiología, Facultad de Veterinaria, Universidad de Santiago de Compostela, Campus Universitario s/n, Lugo 27002, Spain
| | - Carmen Vale
- Departamento
de Farmacología, Farmacia y Tecnología Farmacéutica,
Facultad de Veterinaria, IDIS, Universidad
de Santiago de Compostela, Campus Universitario s/n, Lugo 27002, Spain
| | - Luis M. Botana
- Departamento
de Farmacología, Farmacia y Tecnología Farmacéutica,
Facultad de Veterinaria, IDIS, Universidad
de Santiago de Compostela, Campus Universitario s/n, Lugo 27002, Spain
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3
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Brownlee C, Helliwell KE, Meeda Y, McLachlan D, Murphy EA, Wheeler GL. Regulation and integration of membrane transport in marine diatoms. Semin Cell Dev Biol 2023; 134:79-89. [PMID: 35305902 DOI: 10.1016/j.semcdb.2022.03.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/18/2022] [Accepted: 03/04/2022] [Indexed: 12/27/2022]
Abstract
Diatoms represent one of the most successful groups of marine phytoplankton and are major contributors to ocean biogeochemical cycling. They have colonized marine, freshwater and ice environments and inhabit all regions of the World's oceans, from poles to tropics. Their success is underpinned by a remarkable ability to regulate their growth and metabolism during nutrient limitation and to respond rapidly when nutrients are available. This requires precise regulation of membrane transport and nutrient acquisition mechanisms, integration of nutrient sensing mechanisms and coordination of different transport pathways. This review outlines transport mechanisms involved in acquisition of key nutrients (N, C, P, Si, Fe) by marine diatoms, illustrating their complexity, sophistication and multiple levels of control.
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Affiliation(s)
- Colin Brownlee
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; School of Ocean and Earth Sciences, University of Southampton, Southampton SO14 3ZH, UK
| | - Katherine E Helliwell
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD, UK
| | - Yasmin Meeda
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Deirdre McLachlan
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
| | - Eleanor A Murphy
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
| | - Glen L Wheeler
- Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK
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Wang Z, Yu Z, He L, Zhu J, Liu L, Song X. Establishment and preliminary study of electrophysiological techniques in a typical red tide species. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 840:156698. [PMID: 35710000 DOI: 10.1016/j.scitotenv.2022.156698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/11/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
Electrophysiology studies the electrical properties of cells and tissues including bioelectrical signals and membrane ion channel activities. As an important means to reveal ion channel related physiological functions and the underlying mechanisms, electrophysiological techniques have been widely used in studies of animals, higher plants and algae that are closely related to higher plants. However, few electrophysiological studies have been carried out in red tide organisms, especially in dinoflagellates, which is mainly due to the complex surface structure of dinoflagellate amphiesma. In this study, the surface amphiesma of Alexandrium pacificum, a typical red tide species, was removed by centrifugation, low-temperature treatment and enzymatic treatment. In all three treatments, low-temperature treatment with 4 °C for 2 h had high ecdysis rate and high fixation rate, and the treated cells were easy to puncture, so low-temperature treatment was used as a preprocessing treatment for subsequent current recording. Acquired protoplasts of A. pacificum were identified by calcofluor fluorescence and immobilized by poly-lysine. A modified "puncture" single-electrode voltage-clamp recording was first applied to dinoflagellates, and voltage-gated currents, which had the characteristics of outward K+ current and inward Cl- current, were recorded and confirmed by ion replacement, indicating the voltage-gated currents were mixed. This method can be used as a technical basis for the electrophysiological study of dinoflagellates and provides a new perspective for the study of stress tolerance, red tide succession, and the regulation of physiological function of dinoflagellates.
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Affiliation(s)
- Zhongshi Wang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Zhiming Yu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China.
| | - Liyan He
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Jianan Zhu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Lidong Liu
- The Djavad Mowafaghian Centre for Brian Health and Department of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Xiuxian Song
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
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5
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Colon R, Wheater M, Joyce EJ, Ste Marie EJ, Hondal RJ, Rein KS. The Marine Neurotoxin Brevetoxin (PbTx-2) Inhibits Karenia brevis and Mammalian Thioredoxin Reductases by Targeting Different Residues. JOURNAL OF NATURAL PRODUCTS 2021; 84:2961-2970. [PMID: 34752085 DOI: 10.1021/acs.jnatprod.1c00795] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The brevetoxins, neurotoxins produced by Karenia brevis, the Florida red tide dinoflagellate, effect fish and wildlife mortalities and adverse public health and economic impacts during recurrent blooms. Knowledge of the biochemical consequences of toxin production for K. brevis could provide insights into an endogenous role of the toxins, yet this aspect has not been thoroughly explored. In addition to neurotoxicity, the most abundant of the brevetoxins, PbTx-2, inhibits mammalian thioredoxin reductase (TrxR). The thioredoxin system, composed of the enzymes TrxR and thioredoxin (Trx), is present in all living organisms and is responsible in part for maintaining cellular redox homeostasis. Herein, we describe the cloning, expression, and semisynthesis of the selenoprotein TrxR from K. brevis (KbTrxR) and reductase activity toward a variety of substrates. Unlike mammalian TrxR, KbTrxR reduces oxidized glutathione (GSSG). We further demonstrate that PbTx-2 is an inhibitor of KbTrxR. Covalent adducts between KbTrxR and rat TrxR were detected by mass spectrometry. While both enzymes are adducted at or near the catalytic centers, the specific residues are distinct. Biochemical differences reported for high and low toxin producing strains of K. brevis are consistent with the inhibition of KbTrxR and suggest that PbTx-2 is an endogenous regulator of this critical enzyme.
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Affiliation(s)
- Ricardo Colon
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, Florida 33199, United States
| | - Michelle Wheater
- Department of Biochemistry, University of Vermont, 89 Beaumont Avenue, Given Building Room 413B, Burlington, Vermont 05405, United States
| | - Emily J Joyce
- Department of Biochemistry, University of Vermont, 89 Beaumont Avenue, Given Building Room 413B, Burlington, Vermont 05405, United States
| | - Emma J Ste Marie
- Department of Biochemistry, University of Vermont, 89 Beaumont Avenue, Given Building Room 413B, Burlington, Vermont 05405, United States
| | - Robert J Hondal
- Department of Biochemistry, University of Vermont, 89 Beaumont Avenue, Given Building Room 413B, Burlington, Vermont 05405, United States
| | - Kathleen S Rein
- Department of Chemistry and Biochemistry, Florida International University, 11200 SW 8th Street, Miami, Florida 33199, United States
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Cao X, Guo Z, Wang H, Dong Y, Lu S, He QY, Sun X, Zhang G. Autoactivation of Translation Causes the Bloom of Prorocentrum donghaiense in Harmful Algal Blooms. J Proteome Res 2021; 20:3179-3187. [PMID: 33955761 DOI: 10.1021/acs.jproteome.1c00051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Harmful algal blooms (HABs) are symptomatic of ecosystem imbalance, leading to major worldwide marine natural disasters, and seriously threaten the human health. Some HAB algae's exceptional genome size prohibited the genomic investigations on molecular mechanisms, for example, Prorocentrum. This study performed translatome sequencing (RNC-seq) for Prorocentrum donghaiense to assemble the translatome reference sequences on appropriate cost to enable the global molecular study at translatome and proteome levels. By analyzing the translatome and proteome of P. donghaiense in phosphor-rich, phosphor-deficient, and phosphor-restored media, we found massive up-regulation of energy and material production pathways in phosphor-rich conditions that enables autoactivation of translation, which is the key to its exponential growth in HABs. To break down the autoactivation, we demonstrated that mild translation delay using very low concentrations of cycloheximide efficiently controls the blooming without harming other aquatic organisms and humans. Our result provides a novel hint for controlling HABs and demonstrated the RNC-seq as an economic strategy on investigating functions of organisms with large and unknown genomes.
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Affiliation(s)
- Xin Cao
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, Jinan University, Guangzhou 510632, China
| | - Zhong Guo
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, Jinan University, Guangzhou 510632, China
| | - Hualong Wang
- Key Laboratory of Eutrophication and Red Tide Prevention, Research Center for Harmful Algae and Marine Biology, Jinan University, Guangzhou 510632, China
| | - Yuelei Dong
- Key Laboratory of Eutrophication and Red Tide Prevention, Research Center for Harmful Algae and Marine Biology, Jinan University, Guangzhou 510632, China
| | - Songhui Lu
- Key Laboratory of Eutrophication and Red Tide Prevention, Research Center for Harmful Algae and Marine Biology, Jinan University, Guangzhou 510632, China
| | - Qing-Yu He
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, Jinan University, Guangzhou 510632, China
| | - Xuesong Sun
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, Jinan University, Guangzhou 510632, China
| | - Gong Zhang
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, Jinan University, Guangzhou 510632, China
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7
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Zheng JW, Mao XT, Ye MH, Li HY, Liu JS, Yang WD. Allelopathy and underlying mechanism of Karenia mikimotoi on the diatom Thalassiosira pseudonana under laboratory condition. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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8
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Yates P, Koester JA, Taylor AR. Brevetoxin and Conotoxin Interactions with Single-Domain Voltage-Gated Sodium Channels from a Diatom and Coccolithophore. Mar Drugs 2021; 19:md19030140. [PMID: 33801270 PMCID: PMC8002053 DOI: 10.3390/md19030140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 02/22/2021] [Accepted: 02/26/2021] [Indexed: 01/16/2023] Open
Abstract
The recently characterized single-domain voltage-gated ion channels from eukaryotic protists (EukCats) provide an array of novel channel proteins upon which to test the pharmacology of both clinically and environmentally relevant marine toxins. Here, we examined the effects of the hydrophilic µ-CTx PIIIA and the lipophilic brevetoxins PbTx-2 and PbTx-3 on heterologously expressed EukCat ion channels from a marine diatom and coccolithophore. Surprisingly, none of the toxins inhibited the peak currents evoked by the two EukCats tested. The lack of homology in the outer pore elements of the channel may disrupt the binding of µ-CTx PIIIA, while major structural differences between mammalian sodium channels and the C-terminal domains of the EukCats may diminish interactions with the brevetoxins. However, all three toxins produced significant negative shifts in the voltage dependence of activation and steady state inactivation, suggesting alternative and state-dependent binding conformations that potentially lead to changes in the excitability of the phytoplankton themselves.
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Vallesi A, Pucciarelli S, Buonanno F, Fontana A, Mangiagalli M. Bioactive molecules from protists: Perspectives in biotechnology. Eur J Protistol 2020; 75:125720. [PMID: 32569992 DOI: 10.1016/j.ejop.2020.125720] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 05/11/2020] [Accepted: 05/15/2020] [Indexed: 12/14/2022]
Abstract
For hundreds of years, mankind has benefited from the natural metabolic processes of microorganisms to obtain basic products such as fermented foods and alcoholic beverages. More recently, microorganisms have been exploited for the production of antibiotics, vitamins and enzymes to be used in medicine and chemical industries. Additionally, several modern drugs, including those for cancer therapy, are natural products or their derivatives. Protists are a still underexplored source of natural products potentially of interest for biotechnological and biomedical applications. This paper focuses on some examples of bioactive molecules from protists and associated bacteria and their possible use in biotechnology.
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Affiliation(s)
- Adriana Vallesi
- School of Biosciences and Veterinary Medicine, Università degli Studi di Camerino, Camerino (MC), Italy.
| | - Sandra Pucciarelli
- School of Biosciences and Veterinary Medicine, Università degli Studi di Camerino, Camerino (MC), Italy.
| | - Federico Buonanno
- Laboratory of Protistology and Biology Education, Department of E.C.H.T. Università degli Studi di Macerata, Macerata, Italy
| | - Angelo Fontana
- Bio-Organic Chemistry Unit, CNR-Institute of Biomolecular Chemistry, Pozzuoli, Napoli, Italy
| | - Marco Mangiagalli
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milano, Italy
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Alternative Mechanisms for Fast Na +/Ca 2+ Signaling in Eukaryotes via a Novel Class of Single-Domain Voltage-Gated Channels. Curr Biol 2019; 29:1503-1511.e6. [PMID: 31006567 PMCID: PMC6509283 DOI: 10.1016/j.cub.2019.03.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/11/2019] [Accepted: 03/20/2019] [Indexed: 01/16/2023]
Abstract
Rapid Na+/Ca2+-based action potentials govern essential cellular functions in eukaryotes, from the motile responses of unicellular protists, such as Paramecium [1, 2], to complex animal neuromuscular activity [3]. A key innovation underpinning this fundamental signaling process has been the evolution of four-domain voltage-gated Na+/Ca2+ channels (4D-Cavs/Navs). These channels are widely distributed across eukaryote diversity [4], albeit several eukaryotes, including land plants and fungi, have lost voltage-sensitive 4D-Cav/Navs [5, 6, 7]. Because these lineages appear to lack rapid Na+/Ca2+-based action potentials, 4D-Cav/Navs are generally considered necessary for fast Na+/Ca2+-based signaling [7]. However, the cellular mechanisms underpinning the membrane physiology of many eukaryotes remain unexamined. Eukaryotic phytoplankton critically influence our climate as major primary producers. Several taxa, including the globally abundant diatoms, exhibit membrane excitability [8, 9, 10]. We previously demonstrated that certain diatom genomes encode 4D-Cav/Navs [4] but also proteins of unknown function, resembling prokaryote single-domain, voltage-gated Na+ channels (BacNavs) [4]. Here, we show that single-domain channels are actually broadly distributed across major eukaryote phytoplankton lineages and represent three novel classes of single-domain channels, which we refer collectively to as EukCats. Functional characterization of diatom EukCatAs indicates that they are voltage-gated Na+- and Ca2+-permeable channels, with rapid kinetics resembling metazoan 4D-Cavs/Navs. In Phaeodactylum tricornutum, which lacks 4D-Cav/Navs, EukCatAs underpin voltage-activated Ca2+ signaling important for membrane excitability, and mutants exhibit impaired motility. EukCatAs therefore provide alternative mechanisms for rapid Na+/Ca2+ signaling in eukaryotes and may functionally replace 4D-Cavs/Navs in pennate diatoms. Marine phytoplankton thus possess unique signaling mechanisms that may be key to environmental sensing in the oceans. Novel class of single-domain, voltage-gated channels (EukCatAs) identified in diatoms EukCatAs are fast voltage-gated Na+- and Ca2+-permeable channels EukCatAs underpin voltage-activated Ca2+ signaling and membrane excitability EukCatAs may have functionally replaced 4D-Cav/Nav channels in pennate diatoms
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