1
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Dubey NK, Kumar V, Goswami C. Sperm-Specific CatSper is Not Conserved in All Vertebrates and May Not be the Only Progesterone-Responsive Ion Channel Present in Sperm. J Membr Biol 2024; 257:215-230. [PMID: 38970681 PMCID: PMC11289002 DOI: 10.1007/s00232-024-00316-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Accepted: 06/24/2024] [Indexed: 07/08/2024]
Abstract
Progesterone (P4) acts as a key conserved signalling molecule in vertebrate reproduction. P4 is especially important for mature sperm physiology and subsequent reproductive success. "CatSpermasome", a multi-unit molecular complex, has been suggested to be the main if not the only P4-responsive atypical Ca2+-ion channel present in mature sperm. Altogether, here we analyse the protein sequences of CatSper1-4 from more than 500 vertebrates ranging from early fishes to humans. CatSper1 becomes longer in mammals due to sequence gain mainly at the N-terminus. Overall the conservation of full-length CatSper1-4 as well as the individual TM regions remain low. The lipid-water-interface residues (i.e. a 5 amino acid stretch sequence present on both sides of each TM region) also remain highly diverged. No specific patterns of amino acid distributions were observed. The total frequency of positively charged, negatively charged or their ratios do not follow in any specific pattern. Similarly, the frequency of total hydrophobic, total hydrophilic residues or even their ratios remain random and do not follow any specific pattern. We noted that the CatSper1-4 genes are missing in amphibians and the CatSper1 gene is missing in birds. The high variability of CatSper1-4 and gene-loss in certain clades indicate that the "CatSpermasome" is not the only P4-responsive ion channel. Data indicate that the molecular evolution of CatSper is mostly guided by diverse hydrophobic ligands rather than only P4. The comparative data also suggest possibilities of other Ca2+-channel/s in vertebrate sperm that can also respond to P4.
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Affiliation(s)
- Nishant Kumar Dubey
- School of Biological Sciences, National Institute of Science Education and Research Bhubaneswar, P.O. Jatni, Khurda, 752050, Odisha, India.
- Training School Complex, Homi Bhabha National Institute, Anushakti Nagar, Mumbai, 400094, India.
| | - Vikash Kumar
- School of Biological Sciences, National Institute of Science Education and Research Bhubaneswar, P.O. Jatni, Khurda, 752050, Odisha, India
- Training School Complex, Homi Bhabha National Institute, Anushakti Nagar, Mumbai, 400094, India
| | - Chandan Goswami
- School of Biological Sciences, National Institute of Science Education and Research Bhubaneswar, P.O. Jatni, Khurda, 752050, Odisha, India.
- Training School Complex, Homi Bhabha National Institute, Anushakti Nagar, Mumbai, 400094, India.
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2
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Kang H, Han AR, Zhang A, Jeong H, Koh W, Lee JM, Lee H, Jo HY, Maria-Solano MA, Bhalla M, Kwon J, Roh WS, Yang J, An HJ, Choi S, Kim HM, Lee CJ. GolpHCat (TMEM87A), a unique voltage-dependent cation channel in Golgi apparatus, contributes to Golgi-pH maintenance and hippocampus-dependent memory. Nat Commun 2024; 15:5830. [PMID: 38992057 PMCID: PMC11239671 DOI: 10.1038/s41467-024-49297-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 05/30/2024] [Indexed: 07/13/2024] Open
Abstract
Impaired ion channels regulating Golgi pH lead to structural alterations in the Golgi apparatus, such as fragmentation, which is found, along with cognitive impairment, in Alzheimer's disease. However, the causal relationship between altered Golgi structure and cognitive impairment remains elusive due to the lack of understanding of ion channels in the Golgi apparatus of brain cells. Here, we identify that a transmembrane protein TMEM87A, renamed Golgi-pH-regulating cation channel (GolpHCat), expressed in astrocytes and neurons that contributes to hippocampus-dependent memory. We find that GolpHCat displays unique voltage-dependent currents, which is potently inhibited by gluconate. Additionally, we gain structural insights into the ion conduction through GolpHCat at the molecular level by determining three high-resolution cryogenic-electron microscopy structures of human GolpHCat. GolpHCat-knockout mice show fragmented Golgi morphology and altered protein glycosylation and functions in the hippocampus, leading to impaired spatial memory. These findings suggest a molecular target for Golgi-related diseases and cognitive impairment.
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Affiliation(s)
- Hyunji Kang
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
- IBS School, University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea
| | - Ah-Reum Han
- Center for Biomolecular and Cellular Structure, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Aihua Zhang
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Science, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Heejin Jeong
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 34134, Korea
| | - Wuhyun Koh
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Jung Moo Lee
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Hayeon Lee
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Hee Young Jo
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 34134, Korea
| | - Miguel A Maria-Solano
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Science, Ewha Womans University, Seoul, 03760, Republic of Korea
| | - Mridula Bhalla
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Jea Kwon
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Woo Suk Roh
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Jimin Yang
- Center for Biomolecular and Cellular Structure, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea
| | - Hyun Joo An
- Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, 34134, Korea
| | - Sun Choi
- Global AI Drug Discovery Center, College of Pharmacy and Graduate School of Pharmaceutical Science, Ewha Womans University, Seoul, 03760, Republic of Korea.
| | - Ho Min Kim
- Center for Biomolecular and Cellular Structure, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea.
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
| | - C Justin Lee
- Center for Cognition and Sociality, Life Science Cluster, Institute for Basic Science (IBS), 55 Expo-ro, Yuseong-gu, Daejeon, 34126, Republic of Korea.
- IBS School, University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea.
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3
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Chen H, Xia Z, Dong J, Huang B, Zhang J, Zhou F, Yan R, Shi Y, Gong J, Jiang J, Huang Z, Jiang D. Structural mechanism of voltage-gated sodium channel slow inactivation. Nat Commun 2024; 15:3691. [PMID: 38693179 PMCID: PMC11063143 DOI: 10.1038/s41467-024-48125-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 04/17/2024] [Indexed: 05/03/2024] Open
Abstract
Voltage-gated sodium (NaV) channels mediate a plethora of electrical activities. NaV channels govern cellular excitability in response to depolarizing stimuli. Inactivation is an intrinsic property of NaV channels that regulates cellular excitability by controlling the channel availability. The fast inactivation, mediated by the Ile-Phe-Met (IFM) motif and the N-terminal helix (N-helix), has been well-characterized. However, the molecular mechanism underlying NaV channel slow inactivation remains elusive. Here, we demonstrate that the removal of the N-helix of NaVEh (NaVEhΔN) results in a slow-inactivated channel, and present cryo-EM structure of NaVEhΔN in a potential slow-inactivated state. The structure features a closed activation gate and a dilated selectivity filter (SF), indicating that the upper SF and the inner gate could serve as a gate for slow inactivation. In comparison to the NaVEh structure, NaVEhΔN undergoes marked conformational shifts on the intracellular side. Together, our results provide important mechanistic insights into NaV channel slow inactivation.
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Affiliation(s)
- Huiwen Chen
- Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhanyi Xia
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China
| | - Jie Dong
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Bo Huang
- Beijing StoneWise Technology Co Ltd., 15 Haidian street, Haidian district, Beijing, China
| | - Jiangtao Zhang
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- College of Life Science and Technology, Key Laboratory of Molecular Biophysics of MOE, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Feng Zhou
- Beijing StoneWise Technology Co Ltd., 15 Haidian street, Haidian district, Beijing, China
| | - Rui Yan
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- College of Life Science and Technology, Key Laboratory of Molecular Biophysics of MOE, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yiqiang Shi
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Jianke Gong
- College of Life Science and Technology, Key Laboratory of Molecular Biophysics of MOE, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Juquan Jiang
- Department of Microbiology and Biotechnology, College of Life Sciences, Northeast Agricultural University, No. 600 Changjiang Road, Xiangfang District, Harbin, 150030, China.
| | - Zhuo Huang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, 100191, China.
| | - Daohua Jiang
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China.
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4
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Duran-Urriago A, Marzen S. Not so optimal: The evolution of mutual information in potassium voltage-gated channels. PLoS One 2023; 18:e0264424. [PMID: 36735679 PMCID: PMC9897580 DOI: 10.1371/journal.pone.0264424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 02/10/2022] [Indexed: 02/04/2023] Open
Abstract
Potassium voltage-gated (Kv) channels need to detect and respond to rapidly changing ionic concentrations in their environment. With an essential role in regulating electric signaling, they would be expected to be optimal sensors that evolved to predict the ionic concentrations. To explore these assumptions, we use statistical mechanics in conjunction with information theory to model how animal Kv channels respond to changes in potassium concentrations in their environment. By measuring mutual information in representative Kv channel types across a variety of environments, we find two things. First, under weak conditions, there is a gating charge that maximizes mutual information with the environment. Second, as Kv channels evolved, they have moved towards decreasing mutual information with the environment. This either suggests that Kv channels do not need to act as sensors of their environment or that Kv channels have other functionalities that interfere with their role as sensors of their environment.
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Affiliation(s)
| | - Sarah Marzen
- W. M. Keck Science Department, Pitzer, Scripps, and Claremont McKenna Colleges, Claremont, CA, United States of America
- * E-mail:
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5
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Kelkar S, Nailwal N, Bhatia NY, Doshi G, Sathaye S, Godad AP. An Update On Proficiency of Voltage-gated Ion Channel Blockers in the Treatment of Inflammation-associated Diseases. Curr Drug Targets 2022; 23:1290-1303. [PMID: 35996239 DOI: 10.2174/1389450123666220819141827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/24/2022] [Accepted: 06/21/2022] [Indexed: 01/25/2023]
Abstract
Inflammation is the body's mechanism to trigger the immune system, thereby preventing bacteria and viruses from manifesting their toxic effect. Inflammation plays a vital role in regulating inflammatory mediator levels to initiate the wound healing process depending on the nature of the stimuli. This process occurs due to chemical release from white blood cells by elevating blood flow to the site of action, leading to redness and increased body temperature. Currently, there are numerous Non-steroidal anti-inflammatory drugs (NSAIDs) available, but these drugs are reported with adverse effects such as gastric bleeding, progressive kidney damage, and increased risk of heart attacks when prolonged use. For such instances, alternative options need to be adopted. The introduction of voltage-gated ion channel blockers can be a substantial alternative to mask the side effects of these currently available drugs. Chronic inflammatory disorders such as rheumatoid and osteoarthritis, cancer and migraine, etc., can cause dreadful pain, which is often debilitating for the patient. The underlying mechanism for both acute and chronic inflammation involves various complex receptors, different types of cells, receptors, and proteins. The working of voltage-gated sodium and calcium channels is closely linked to both inflammatory and neuropathic pain. Certain drugs such as carbamazepine and gabapentin, which are ion channel blockers, have greater pharmacotherapeutic activity for sodium and calcium channel blockers for the treatment of chronic inflammatory pain states. This review intends to provide brief information on the mechanism of action, latest clinical trials, and applications of these blockers in treating inflammatory conditions.
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Affiliation(s)
- Siddesh Kelkar
- MET Institute of Pharmacy, Bhujbal Knowledge City, Reclamation, Bandra West, Mumbai, Maharashtra 400050, India
| | - Namrata Nailwal
- SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mithibai College Campus, Vaikunthlal Mehta Rd, Vile Parle West, Mumbai, Maharashtra 400056, India
| | - Nirav Yogesh Bhatia
- SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mithibai College Campus, Vaikunthlal Mehta Rd, Vile Parle West, Mumbai, Maharashtra 400056, India
| | - Gaurav Doshi
- SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mithibai College Campus, Vaikunthlal Mehta Rd, Vile Parle West, Mumbai, Maharashtra 400056, India
| | - Sadhana Sathaye
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, Mumbai, India
| | - Angel Pavalu Godad
- SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mithibai College Campus, Vaikunthlal Mehta Rd, Vile Parle West, Mumbai, Maharashtra 400056, India.,Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, Mumbai, India
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6
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N-type fast inactivation of a eukaryotic voltage-gated sodium channel. Nat Commun 2022; 13:2713. [PMID: 35581266 PMCID: PMC9114117 DOI: 10.1038/s41467-022-30400-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/28/2022] [Indexed: 12/19/2022] Open
Abstract
Voltage-gated sodium (NaV) channels initiate action potentials. Fast inactivation of NaV channels, mediated by an Ile-Phe-Met motif, is crucial for preventing hyperexcitability and regulating firing frequency. Here we present cryo-electron microscopy structure of NaVEh from the coccolithophore Emiliania huxleyi, which reveals an unexpected molecular gating mechanism for NaV channel fast inactivation independent of the Ile-Phe-Met motif. An N-terminal helix of NaVEh plugs into the open activation gate and blocks it. The binding pose of the helix is stabilized by multiple electrostatic interactions. Deletion of the helix or mutations blocking the electrostatic interactions completely abolished the fast inactivation. These strong interactions enable rapid inactivation, but also delay recovery from fast inactivation, which is ~160-fold slower than human NaV channels. Together, our results provide mechanistic insights into fast inactivation of NaVEh that fundamentally differs from the conventional local allosteric inhibition, revealing both surprising structural diversity and functional conservation of ion channel inactivation.
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7
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The Quantum Tunneling of Ions Model Can Explain the Pathophysiology of Tinnitus. Brain Sci 2022; 12:brainsci12040426. [PMID: 35447958 PMCID: PMC9025927 DOI: 10.3390/brainsci12040426] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/16/2022] [Accepted: 03/19/2022] [Indexed: 02/04/2023] Open
Abstract
Tinnitus is a well-known pathological entity in clinical practice. However, the pathophysiological mechanisms behind tinnitus seem to be elusive and cannot provide a comprehensive understanding of its pathogenesis and clinical manifestations. Hence, in the present study, we explore the mathematical model of ions’ quantum tunneling to propose an original pathophysiological mechanism for the sensation of tinnitus. The present model focuses on two major aspects: The first aspect is the ability of ions, including sodium, potassium, and calcium, to depolarize the membrane potential of inner hair cells and the neurons of the auditory pathway. This membrane depolarization is induced via the quantum tunneling of ions through closed voltage-gated channels. The state of membrane depolarization can be a state of hyper-excitability or hypo-excitability, depending on the degree of depolarization. Both of these states aid in understanding the pathophysiology of tinnitus. The second aspect is the quantum tunneling signals between the demyelinated neurons of the auditory pathway. These signals are mediated via the quantum tunneling of potassium ions, which exit to the extracellular fluid during an action potential event. These quantum signals can be viewed as a “quantum synapse” between neurons. The formation of quantum synapses results in hyper-excitability among the demyelinated neurons of the auditory pathway. Both of these aspects augment and amplify the electrical signals in the auditory pathway and result in a loss of the spatiotemporal fidelity of sound signals going to the brain centers. The brain interprets this hyper-excitability and loss of spatiotemporal fidelity as tinnitus. Herein, we show mathematically that the quantum tunneling of ions can depolarize the membrane potential of the inner hair cells and neurons of the auditory pathway. Moreover, we calculate the probability of action potential induction in the neurons of the auditory pathway generated by the quantum tunneling signals of potassium ions.
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8
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Dong Y, Gao Y, Xu S, Wang Y, Yu Z, Li Y, Li B, Yuan T, Yang B, Zhang XC, Jiang D, Huang Z, Zhao Y. Closed-state inactivation and pore-blocker modulation mechanisms of human Ca V2.2. Cell Rep 2021; 37:109931. [PMID: 34731621 DOI: 10.1016/j.celrep.2021.109931] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/13/2021] [Accepted: 10/11/2021] [Indexed: 11/19/2022] Open
Abstract
N-type voltage-gated calcium (CaV) channels mediate Ca2+ influx at presynaptic terminals in response to action potentials and play vital roles in synaptogenesis, release of neurotransmitters, and nociceptive transmission. Here, we elucidate a cryo-electron microscopy (cryo-EM) structure of the human CaV2.2 complex in apo, ziconotide-bound, and two CaV2.2-specific pore blockers-bound states. The second voltage-sensing domain (VSD) is captured in a resting-state conformation, trapped by a phosphatidylinositol 4,5-bisphosphate (PIP2) molecule, which is distinct from the other three VSDs of CaV2.2, as well as activated VSDs observed in previous structures of CaV channels. This structure reveals the molecular basis for the unique inactivation process of CaV2.2 channels, in which the intracellular gate formed by S6 helices is closed and a W-helix from the domain II-III linker stabilizes closed-state inactivation. The structures of this inactivated, drug-bound complex lay a solid foundation for developing new state-dependent blockers for treatment of chronic pain.
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Affiliation(s)
- Yanli Dong
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiwei Gao
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuai Xu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Yuhang Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhuoya Yu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yue Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bin Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tian Yuan
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Bei Yang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuejun Cai Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Daohua Jiang
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Zhuo Huang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100191, China; IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China.
| | - Yan Zhao
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
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9
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Panagopoulos DJ, Karabarbounis A, Yakymenko I, Chrousos GP. Human‑made electromagnetic fields: Ion forced‑oscillation and voltage‑gated ion channel dysfunction, oxidative stress and DNA damage (Review). Int J Oncol 2021; 59:92. [PMID: 34617575 PMCID: PMC8562392 DOI: 10.3892/ijo.2021.5272] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 08/23/2021] [Indexed: 12/13/2022] Open
Abstract
Exposure of animals/biological samples to human‑made electromagnetic fields (EMFs), especially in the extremely low frequency (ELF) band, and the microwave/radio frequency (RF) band which is always combined with ELF, may lead to DNA damage. DNA damage is connected with cell death, infertility and other pathologies, including cancer. ELF exposure from high‑voltage power lines and complex RF exposure from wireless communication antennas/devices are linked to increased cancer risk. Almost all human‑made RF EMFs include ELF components in the form of modulation, pulsing and random variability. Thus, in addition to polarization and coherence, the existence of ELFs is a common feature of almost all human‑made EMFs. The present study reviews the DNA damage and related effects induced by human‑made EMFs. The ion forced‑oscillation mechanism for irregular gating of voltage‑gated ion channels on cell membranes by polarized/coherent EMFs is extensively described. Dysfunction of ion channels disrupts intracellular ionic concentrations, which determine the cell's electrochemical balance and homeostasis. The present study shows how this can result in DNA damage through reactive oxygen species/free radical overproduction. Thus, a complete picture is provided of how human‑made EMF exposure may indeed lead to DNA damage and related pathologies, including cancer. Moreover, it is suggested that the non‑thermal biological effects attributed to RF EMFs are actually due to their ELF components.
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Affiliation(s)
- Dimitris J. Panagopoulos
- Laboratory of Health Physics, Radiobiology and Cytogenetics, Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety, National Center for Scientific Research 'Demokritos', 15310 Athens, Greece
- Choremeion Research Laboratory, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
- Electromagnetic Field-Biophysics Research Laboratory, 10681 Athens, Greece
| | - Andreas Karabarbounis
- Department of Physics, Section of Nuclear and Particle Physics, National and Kapodistrian University of Athens, 15784 Athens, Greece
| | - Igor Yakymenko
- Institute of Experimental Pathology, Oncology and Radiobiology of National Academy of Science of Ukraine, 03022 Kyiv, Ukraine
- Department of Public Health, Kyiv Medical University, 02000 Kyiv, Ukraine
| | - George P. Chrousos
- Choremeion Research Laboratory, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
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10
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Ababneh O, Qaswal AB, Alelaumi A, Khreesha L, Almomani M, Khrais M, Khrais O, Suleihat A, Mutleq S, Al-olaimat Y, Nawafleh S. Proton Quantum Tunneling: Influence and Relevance to Acidosis-Induced Cardiac Arrhythmias/Cardiac Arrest. PATHOPHYSIOLOGY 2021; 28:400-436. [PMID: 35366283 PMCID: PMC8830476 DOI: 10.3390/pathophysiology28030027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/23/2021] [Accepted: 08/31/2021] [Indexed: 01/10/2023] Open
Abstract
Acidosis and its associated pathologies predispose patients to develop cardiac arrhythmias and even cardiac arrest. These arrhythmias are assumed to be the result of membrane depolarization, however, the exact mechanism of depolarization during acidosis is not well defined. In our study, the model of quantum tunneling of protons is used to explain the membrane depolarization that occurs during acidosis. It is found that protons can tunnel through closed activation and inactivation gates of voltage-gated sodium channels Nav1.5 that are present in the membrane of cardiac cells. The quantum tunneling of protons results in quantum conductance, which is evaluated to assess its effect on membrane potential. The quantum conductance of extracellular protons is higher than that of intracellular protons. This predicts an inward quantum current of protons through the closed sodium channels. Additionally, the values of quantum conductance are influential and can depolarize the membrane potential according to the quantum version of the GHK equation. The quantum mechanism of depolarization is distinct from other mechanisms because the quantum model suggests that protons can directly depolarize the membrane potential, and not only through indirect effects as proposed by other mechanisms in the literature. Understanding the pathophysiology of arrhythmias mediated by depolarization during acidosis is crucial to treat and control them and to improve the overall clinical outcomes of patients.
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Affiliation(s)
- Omar Ababneh
- Department of Anesthesia and Intensive Care, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Abdallah Barjas Qaswal
- Department of Internal Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan
| | - Ahmad Alelaumi
- Department of Orthopedic Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Lubna Khreesha
- Department of Special Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Mujahed Almomani
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (M.A.); (M.K.); (O.K.); (A.S.)
| | - Majdi Khrais
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (M.A.); (M.K.); (O.K.); (A.S.)
| | - Oweiss Khrais
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (M.A.); (M.K.); (O.K.); (A.S.)
| | - Ahmad Suleihat
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (M.A.); (M.K.); (O.K.); (A.S.)
| | - Shahed Mutleq
- Department of Family Medicine, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Yazan Al-olaimat
- Department of Neurosurgery, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Sager Nawafleh
- Department of Anesthesia and Intensive Care Unit, The Hashemite University, Zarqa 13115, Jordan;
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11
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Rajeshwari M, Karthi S, Singh R, Efthymiou S, Gowda VK, Varalakshmi P, Srinivasan VM, Houlden H, Keller MA, Rizzo WB, Ashokkumar B. Novel ALDH3A2 mutations in structural and functional domains of FALDH causing diverse clinical phenotypes in Sjögren-Larsson syndrome patients. Hum Mutat 2021; 42:1015-1029. [PMID: 34082469 DOI: 10.1002/humu.24236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/06/2021] [Accepted: 05/27/2021] [Indexed: 11/07/2022]
Abstract
Mutations in ALDH3A2 cause Sjögren-Larsson syndrome (SLS), a neuro-ichthyotic condition due to the deficiency of fatty aldehyde dehydrogenase (FALDH). We screened for novel mutations causing SLS among Indian ethnicity, characterized the identified mutations in silico and in vitro, and retrospectively evaluated their role in phenotypic heterogeneity. Interestingly, asymmetric distribution of nonclassical traits was observed in our cases. Nerve conduction studies suggested intrinsic-minus-claw hands in two siblings, a novel neurological phenotype to SLS. Genetic testing revealed five novel homozygous ALDH3A2 mutations in six cases: Case-1-NM_000382.2:c.50C>A, NP_000373.1:p.(Ser17Ter); Case-2-NM_000382.2:c.199G>T, NP_000373.1:p.(Glu67Ter); Case-3-NM_000382.2:c.1208G>A, NP_000373.1:p.(Gly403Asp); Case-4-NM_000382.2:c.1325C>T, NP_000373.1:p.(Pro442Leu); Case-5 and -6 NM_000382.2:c.1349G>A, NP_000373.1:p.(Trp450Ter). The mutations identified were predicted to be pathogenic and disrupt the functional domains of the FALDH. p.(Pro442Leu) at the C-terminal α-helix, might impair the substrate gating process. Mammalian expression studies with exon-9 mutants confirmed the profound reduction in the enzyme activity. Diminished aldehyde-oxidizing activity was observed with cases-2 and 3. Cases-2 and 3 showed epidermal hyperplasia with mild intracellular edema, spongiosis, hypergranulosis, and perivascular-interstitial lymphocytic infiltrate and a leaky eosinophilic epidermis. The presence of keratin-containing milia-like lipid vacuoles implies defective lamellar secretion with p.(Gly403Asp). This study improves our understanding of the clinical and mutational diversity in SLS, which might help to fast-track diagnostic and therapeutic interventions of this debilitating disorder.
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Affiliation(s)
- Mohan Rajeshwari
- School of Biotechnology, Madurai Kamaraj University, Madurai, India
| | - Sellamuthu Karthi
- Department of Biochemistry & Molecular Biology, Sealy Center for Molecular Medicine, UTMB, Gavelston, Texas, USA
| | - Reetu Singh
- School of Biotechnology, Madurai Kamaraj University, Madurai, India
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, UCL Institute of Neurology, London, UK
| | - Vykuntaraju K Gowda
- Department of Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, India
| | | | | | - Henry Houlden
- Department of Neuromuscular Disorders, UCL Institute of Neurology, London, UK
| | - Markus A Keller
- Human Genetics Section, Medical University of Innsbruck, Innsbruck, Austria
| | - William B Rizzo
- Division of Inherited Metabolic Diseases, University of Nebraska Medical Center, Omaha, Nebraska, USA
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12
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Zequn Z, Jiangfang L. Molecular Insights Into the Gating Kinetics of the Cardiac hERG Channel, Illuminated by Structure and Molecular Dynamics. Front Pharmacol 2021; 12:687007. [PMID: 34168566 PMCID: PMC8217747 DOI: 10.3389/fphar.2021.687007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 05/20/2021] [Indexed: 11/13/2022] Open
Abstract
The rapidly activating delayed rectifier K+ current generated by the cardiac hERG potassium channel encoded by KCNH2 is the most important reserve current for cardiac repolarization. The unique inward rectification characteristics of the hERG channel depend on the gating regulation, which involves crucial structural domains and key single amino acid residues in the full-length hERG channel. Identifying critical molecules involved in the regulation of gating kinetics for the hERG channel requires high-resolution structures and molecular dynamics simulation models. Based on the latest progress in hERG structure and molecular dynamics simulation research, summarizing the molecules involved in the changes in the channel state helps to elucidate the unique gating characteristics of the channel and the reason for its high affinity to cardiotoxic drugs. In this review, we aim to summarize the significant advances in understanding the voltage gating regulation of the hERG channel based on its structure obtained from cryo-electron microscopy and computer simulations, which reveal the critical roles of several specific structural domains and amino acid residues.
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Affiliation(s)
- Zheng Zequn
- Department of Cardiovascular, Medical College, Ningbo University, Ningbo, China
| | - Lian Jiangfang
- Department of Cardiovascular, Lihuili Hospital Affiliated to Ningbo University, Ningbo, China
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13
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Structural Pharmacology of Voltage-Gated Sodium Channels. J Mol Biol 2021; 433:166967. [PMID: 33794261 DOI: 10.1016/j.jmb.2021.166967] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/22/2021] [Accepted: 03/22/2021] [Indexed: 12/19/2022]
Abstract
Voltage-gated sodium (NaV) channels initiate and propagate action potentials in excitable tissues to mediate key physiological processes including heart contraction and nervous system function. Accordingly, NaV channels are major targets for drugs, toxins and disease-causing mutations. Recent breakthroughs in cryo-electron microscopy have led to the visualization of human NaV1.1, NaV1.2, NaV1.4, NaV1.5 and NaV1.7 channel subtypes at high-resolution. These landmark studies have greatly advanced our structural understanding of channel architecture, ion selectivity, voltage-sensing, electromechanical coupling, fast inactivation, and the molecular basis underlying NaV channelopathies. NaV channel structures have also been increasingly determined in complex with toxin and small molecule modulators that target either the pore module or voltage sensor domains. These structural studies have provided new insights into the mechanisms of pharmacological action and opportunities for subtype-selective NaV channel drug design. This review will highlight the structural pharmacology of human NaV channels as well as the potential use of engineered and chimeric channels in future drug discovery efforts.
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14
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Qaswal AB, Ababneh O, Khreesha L, Al-Ani A, Suleihat A, Abbad M. Mathematical Modeling of Ion Quantum Tunneling Reveals Novel Properties of Voltage-Gated Channels and Quantum Aspects of Their Pathophysiology in Excitability-Related Disorders. PATHOPHYSIOLOGY 2021; 28:116-154. [PMID: 35366274 PMCID: PMC8830480 DOI: 10.3390/pathophysiology28010010] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 02/08/2023] Open
Abstract
Voltage-gated channels are crucial in action potential initiation and propagation and there are many diseases and disorders related to them. Additionally, the classical mechanics are the main mechanics used to describe the function of the voltage-gated channels and their related abnormalities. However, the quantum mechanics should be considered to unravel new aspects in the voltage-gated channels and resolve the problems and challenges that classical mechanics cannot solve. In the present study, the aim is to mathematically show that quantum mechanics can exhibit a powerful tendency to unveil novel electrical features in voltage-gated channels and be used as a promising tool to solve the problems and challenges in the pathophysiology of excitability-related diseases. The model of quantum tunneling of ions through the intracellular hydrophobic gate is used to evaluate the influence of membrane potential and gating free energy on the tunneling probability, single channel conductance, and quantum membrane conductance. This evaluation is mainly based on graphing the mathematical relationships between these variables. The obtained mathematical graphs showed that ions can achieve significant quantum membrane conductance, which can affect the resting membrane potential and the excitability of cells. In the present work, quantum mechanics reveals original electrical properties associated with voltage-gated channels and introduces new insights and implications into the pathophysiology of excitability- related disorders. In addition, the present work sets a mathematical and theoretical framework that can be utilized to conduct experimental studies in order to explore the quantum aspects of voltage-gated channels and the quantum bioelectrical property of biological membranes.
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Affiliation(s)
- Abdallah Barjas Qaswal
- Department of Internship Program, Jordan University Hospital, The University of Jordan, Amman 11942, Jordan
| | - Omar Ababneh
- Department of Anesthesia and Intensive Care, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Lubna Khreesha
- Department of Special Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Abdallah Al-Ani
- School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Ahmad Suleihat
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (A.S.); (M.A.)
| | - Mutaz Abbad
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (A.S.); (M.A.)
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15
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Neural signal analysis with memristor arrays towards high-efficiency brain-machine interfaces. Nat Commun 2020; 11:4234. [PMID: 32843643 PMCID: PMC7447752 DOI: 10.1038/s41467-020-18105-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 07/31/2020] [Indexed: 12/21/2022] Open
Abstract
Brain-machine interfaces are promising tools to restore lost motor functions and probe brain functional mechanisms. As the number of recording electrodes has been exponentially rising, the signal processing capability of brain–machine interfaces is falling behind. One of the key bottlenecks is that they adopt conventional von Neumann architecture with digital computation that is fundamentally different from the working principle of human brain. In this work, we present a memristor-based neural signal analysis system, where the bio-plausible characteristics of memristors are utilized to analyze signals in the analog domain with high efficiency. As a proof-of-concept demonstration, memristor arrays are used to implement the filtering and identification of epilepsy-related neural signals, achieving a high accuracy of 93.46%. Remarkably, our memristor-based system shows nearly 400× improvements in the power efficiency compared to state-of-the-art complementary metal-oxide-semiconductor systems. This work demonstrates the feasibility of using memristors for high-performance neural signal analysis in next-generation brain–machine interfaces. Designing energy efficient and high performance brain-machine interfaces with millions of recording electrodes for in-situ analysis remains a challenge. Here, the authors develop a memristor-based neural signal analysis system capable of filtering and identifying epilepsy-related brain activities with an accuracy of 93.46%.
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16
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Galotti A, Jiménez-Gómez F, Parra G. Flow Cytometry Assessment of Microalgae Physiological Alterations under CO 2 Injection. Cytometry A 2020; 97:1136-1144. [PMID: 32427422 DOI: 10.1002/cyto.a.24028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/30/2020] [Accepted: 04/09/2020] [Indexed: 01/13/2023]
Abstract
Growth rate (GR), esterase activity (EA), membrane potential (MP), and DNA content were measured by flow cytometry to test if this powerful tool could be included in risk assessment and monitoring programs. This study tests a battery of endpoints that were measured on Scenedesmus (Acutodesmus) obliquus as model species, under high levels of injected CO2 to be proposed as biomarkers of effect. New technologies such as carbon capture and storage (CCS) bring positive consequences on CO2 mitigation strategies but also could have negative consequences if a CO2 leakage occurs during injection. Under this scenario, pH might drop down to 4 pH units around the pipe where the leakage happens. The study focus on to ascertain if the endpoints fulfill the requirements such as sensitiveness, be timely and cost-effective, be easy to measure and interpret, and be nondestructive, valuable attributes in effective biomarkers. CO2 injected at high levels significantly affects the EA, the membrane polarization, as well as GRs. However the DNA content did not shown a clear response under this condition. In conclusion, the GR, the EA, and the MP analyzed by flow cytometry fulfilled the attributes mentioned above and are proposed as biomarkers of effect in CCS monitoring programs. © 2020 International Society for Advancement of Cytometry.
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Affiliation(s)
- Andréa Galotti
- Department of Animal Biology, Plant Biology and Ecology, University of Jaén, Jaén, Spain.,Centre of Advanced Studies in Earth Sciences, University of Jaén, Jaén, Spain
| | - Francisco Jiménez-Gómez
- Department of Animal Biology, Plant Biology and Ecology, University of Jaén, Jaén, Spain.,Centre of Advanced Studies in Earth Sciences, University of Jaén, Jaén, Spain
| | - Gema Parra
- Department of Animal Biology, Plant Biology and Ecology, University of Jaén, Jaén, Spain.,Centre of Advanced Studies in Earth Sciences, University of Jaén, Jaén, Spain
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17
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Brewer KR, Kuenze G, Vanoye CG, George AL, Meiler J, Sanders CR. Structures Illuminate Cardiac Ion Channel Functions in Health and in Long QT Syndrome. Front Pharmacol 2020; 11:550. [PMID: 32431610 PMCID: PMC7212895 DOI: 10.3389/fphar.2020.00550] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 04/09/2020] [Indexed: 12/13/2022] Open
Abstract
The cardiac action potential is critical to the production of a synchronized heartbeat. This electrical impulse is governed by the intricate activity of cardiac ion channels, among them the cardiac voltage-gated potassium (Kv) channels KCNQ1 and hERG as well as the voltage-gated sodium (Nav) channel encoded by SCN5A. Each channel performs a highly distinct function, despite sharing a common topology and structural components. These three channels are also the primary proteins mutated in congenital long QT syndrome (LQTS), a genetic condition that predisposes to cardiac arrhythmia and sudden cardiac death due to impaired repolarization of the action potential and has a particular proclivity for reentrant ventricular arrhythmias. Recent cryo-electron microscopy structures of human KCNQ1 and hERG, along with the rat homolog of SCN5A and other mammalian sodium channels, provide atomic-level insight into the structure and function of these proteins that advance our understanding of their distinct functions in the cardiac action potential, as well as the molecular basis of LQTS. In this review, the gating, regulation, LQTS mechanisms, and pharmacological properties of KCNQ1, hERG, and SCN5A are discussed in light of these recent structural findings.
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Affiliation(s)
- Kathryn R. Brewer
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Biochemistry, Vanderbilt University, Nashville, TN, United States
| | - Georg Kuenze
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Carlos G. Vanoye
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Alfred L. George
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
- Department of Pharmacology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Institute for Drug Discovery, Leipzig University Medical School, Leipzig, Germany
| | - Charles R. Sanders
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Biochemistry, Vanderbilt University, Nashville, TN, United States
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18
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Zhang XC, Li B. Towards understanding the mechanisms of proton pumps in Complex-I of the respiratory chain. BIOPHYSICS REPORTS 2019. [DOI: 10.1007/s41048-019-00094-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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19
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Zhang XC, Zhang H. P-type ATPases use a domain-association mechanism to couple ATP hydrolysis to conformational change. BIOPHYSICS REPORTS 2019. [DOI: 10.1007/s41048-019-0087-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
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20
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Zhang XC, Li H. Interplay between the electrostatic membrane potential and conformational changes in membrane proteins. Protein Sci 2019; 28:502-512. [PMID: 30549351 DOI: 10.1002/pro.3563] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 12/12/2018] [Accepted: 12/13/2018] [Indexed: 12/16/2022]
Abstract
Transmembrane electrostatic membrane potential is a major energy source of the cell. Importantly, it determines the structure as well as function of charge-carrying membrane proteins. Here, we discuss the relationship between membrane potential and membrane proteins, in particular whether the conformation of these proteins is integrally connected to the membrane potential. Together, these concepts provide a framework for rationalizing the types of conformational changes that have been observed in membrane proteins and for better understanding the electrostatic effects of the membrane potential on both reversible as well as unidirectional dynamic processes of membrane proteins.
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Affiliation(s)
- Xuejun C Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hang Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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21
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Zhang XC, Liu M. Energy coupling mechanism of FO in a rotary ATP synthase: a model update. BIOPHYSICS REPORTS 2018. [DOI: 10.1007/s41048-018-0077-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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