1
|
Cole BA, Kalli AC, Pilati N, Muench SP, Lippiat JD. A molecular switch in RCK2 triggers sodium-dependent activation of K Na1.1 (KCNT1) potassium channels. Biophys J 2024; 123:2145-2153. [PMID: 38605520 DOI: 10.1016/j.bpj.2024.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/12/2024] [Accepted: 04/08/2024] [Indexed: 04/13/2024] Open
Abstract
The Na+-activated K+ channel KNa1.1, encoded by the KCNT1 gene, is an important regulator of neuronal excitability. How intracellular Na+ ions bind and increase channel activity is not well understood. Analysis of KNa1.1 channel structures indicate that there is a large twisting of the βN-αQ loop in the intracellular RCK2 domain between the inactive and Na+-activated conformations, with a lysine (K885, human subunit numbering) close enough to potentially form a salt bridge with an aspartate (D839) in βL in the Na+-activated state. Concurrently, an aspartate (D884) adjacent in the same loop adopts a position within a pocket formed by the βO strand. In carrying out mutagenesis and electrophysiology with human KNa1.1, we found that alanine substitution of selected residues in these regions resulted in almost negligible currents in the presence of up to 40 mM intracellular Na+. The exception was D884A, which resulted in constitutively active channels in both the presence and absence of intracellular Na+. Further mutagenesis of this site revealed an amino acid size-dependent effect. Substitutions at this site by an amino acid smaller than aspartate (D884V) also yielded constitutively active KNa1.1, and D884I had Na+ dependence similar to wild-type KNa1.1, while increasing the side-chain size larger than aspartate (D884E or D884F) yielded channels that could not be activated by up to 40 mM intracellular Na+. We conclude that Na+ binding results in a conformational change that accommodates D884 in the βO pocket, which triggers further conformational changes in the RCK domains and channel activation.
Collapse
Affiliation(s)
- Bethan A Cole
- School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom
| | - Antreas C Kalli
- Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom; Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, United Kingdom
| | | | - Stephen P Muench
- School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom; Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Jonathan D Lippiat
- School of Biomedical Sciences, University of Leeds, Leeds, United Kingdom.
| |
Collapse
|
2
|
Lyon MD, Ferreira JJ, Li P, Bhagwat S, Butler A, Anderson K, Polo M, Santi CM. SLO3: A Conserved Regulator of Sperm Membrane Potential. Int J Mol Sci 2023; 24:11205. [PMID: 37446382 DOI: 10.3390/ijms241311205] [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: 05/25/2023] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/15/2023] Open
Abstract
Sperm cells must undergo a complex maturation process after ejaculation to be able to fertilize an egg. One component of this maturation is hyperpolarization of the membrane potential to a more negative value. The ion channel responsible for this hyperpolarization, SLO3, was first cloned in 1998, and since then much progress has been made to determine how the channel is regulated and how its function intertwines with various signaling pathways involved in sperm maturation. Although Slo3 was originally thought to be present only in the sperm of mammals, recent evidence suggests that a primordial form of the gene is more widely expressed in some fish species. Slo3, like many reproductive genes, is rapidly evolving with low conservation between closely related species and different regulatory and pharmacological profiles. Despite these differences, SLO3 appears to have a conserved role in regulating sperm membrane potential and driving large changes in response to stimuli. The effect of this hyperpolarization of the membrane potential may vary among mammalian species just as the regulation of the channel does. Recent discoveries have elucidated the role of SLO3 in these processes in human sperm and provided tools to target the channel to affect human fertility.
Collapse
Affiliation(s)
- Maximilian D Lyon
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Juan J Ferreira
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ping Li
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Shweta Bhagwat
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Alice Butler
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kelsey Anderson
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Maria Polo
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Celia M Santi
- Department of Obstetrics and Gynecology, Washington University in St. Louis, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, MO 63110, USA
| |
Collapse
|
3
|
Wang W, Yao J, Li W, Wu Y, Duan H, Xu C, Tian X, Li S, Tan Q, Zhang D. Epigenome-wide association study in Chinese monozygotic twins identifies DNA methylation loci associated with blood pressure. Clin Epigenetics 2023; 15:38. [PMID: 36869404 PMCID: PMC9985232 DOI: 10.1186/s13148-023-01457-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 02/24/2023] [Indexed: 03/05/2023] Open
Abstract
BACKGROUND Hypertension is a crucial risk factor for developing cardiovascular disease and reducing life expectancy. We aimed to detect DNA methylation (DNAm) variants potentially related to systolic blood pressure (SBP) and diastolic blood pressure (DBP) by conducting epigenome-wide association studies in 60 and 59 Chinese monozygotic twin pairs, respectively. METHODS Genome-wide DNA methylation profiling in whole blood of twins was performed using Reduced Representation Bisulfite Sequencing, yielding 551,447 raw CpGs. Association between DNAm of single CpG and blood pressure was tested by applying generalized estimation equation. Differentially methylated regions (DMRs) were identified by comb-P approach. Inference about Causation through Examination of Familial Confounding was utilized to perform the causal inference. Ontology enrichment analysis was performed using Genomic Regions Enrichment of Annotations Tool. Candidate CpGs were quantified using Sequenom MassARRAY platform in a community population. Weighted gene co-expression network analysis (WGCNA) was conducted using gene expression data. RESULTS The median age of twins was 52 years (95% range 40, 66). For SBP, 31 top CpGs (p < 1 × 10-4) and 8 DMRs were identified, with several DMRs within NFATC1, CADM2, IRX1, COL5A1, and LRAT. For DBP, 43 top CpGs (p < 1 × 10-4) and 12 DMRs were identified, with several DMRs within WNT3A, CNOT10, and DAB2IP. Important pathways, such as Notch signaling pathway, p53 pathway by glucose deprivation, and Wnt signaling pathway, were significantly enriched for SBP and DBP. Causal inference analysis suggested that DNAm at top CpGs within NDE1, MYH11, SRRM1P2, and SMPD4 influenced SBP, while SBP influenced DNAm at CpGs within TNK2. DNAm at top CpGs within WNT3A influenced DBP, while DBP influenced DNAm at CpGs within GNA14. Three CpGs mapped to WNT3A and one CpG mapped to COL5A1 were validated in a community population, with a hypermethylated and hypomethylated direction in hypertension cases, respectively. Gene expression analysis by WGCNA further identified some common genes and enrichment terms. CONCLUSION We detect many DNAm variants that may be associated with blood pressure in whole blood, particularly the loci within WNT3A and COL5A1. Our findings provide new clues to the epigenetic modification underlying hypertension pathogenesis.
Collapse
Affiliation(s)
- Weijing Wang
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, No. 308 Ningxia Road, Qingdao, 266021, Shandong, China
| | - Jie Yao
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, No. 308 Ningxia Road, Qingdao, 266021, Shandong, China
- Jiangsu Health Development Research Center, Nanjing, Jiangsu, China
| | - Weilong Li
- Population Research Unit, Faculty of Social Sciences, University of Helsinki, Helsinki, Finland
| | - Yili Wu
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, No. 308 Ningxia Road, Qingdao, 266021, Shandong, China
| | - Haiping Duan
- Qingdao Municipal Center for Disease Control and Prevention/Qingdao Institute of Preventive Medicine, Qingdao, Shandong, China
| | - Chunsheng Xu
- Qingdao Municipal Center for Disease Control and Prevention/Qingdao Institute of Preventive Medicine, Qingdao, Shandong, China
| | - Xiaocao Tian
- Qingdao Municipal Center for Disease Control and Prevention/Qingdao Institute of Preventive Medicine, Qingdao, Shandong, China
| | - Shuxia Li
- Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Qihua Tan
- Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Dongfeng Zhang
- Department of Epidemiology and Health Statistics, Public Health College, Qingdao University, No. 308 Ningxia Road, Qingdao, 266021, Shandong, China.
| |
Collapse
|
4
|
Elenbaas JS, Pudupakkam U, Ashworth KJ, Kang CJ, Patel V, Santana K, Jung IH, Lee PC, Burks KH, Amrute JM, Mecham RP, Halabi CM, Alisio A, Di Paola J, Stitziel NO. SVEP1 is an endogenous ligand for the orphan receptor PEAR1. Nat Commun 2023; 14:850. [PMID: 36792666 PMCID: PMC9932102 DOI: 10.1038/s41467-023-36486-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 01/30/2023] [Indexed: 02/17/2023] Open
Abstract
Sushi, von Willebrand factor type A, EGF and pentraxin domain containing 1 (SVEP1) is an extracellular matrix protein that causally promotes vascular disease and associates with platelet reactivity in humans. Here, using a human genomic and proteomic approach, we identify a high affinity, disease-relevant, and potentially targetable interaction between SVEP1 and the orphan receptor Platelet and Endothelial Aggregation Receptor 1 (PEAR1). This interaction promotes PEAR1 phosphorylation and disease associated AKT/mTOR signaling in vascular cells and platelets. Mice lacking SVEP1 have reduced platelet activation, and exogenous SVEP1 induces PEAR1-dependent activation of platelets. SVEP1 and PEAR1 causally and concordantly relate to platelet phenotypes and cardiovascular disease in humans, as determined by Mendelian Randomization. Targeting this receptor-ligand interaction may be a viable therapeutic strategy to treat or prevent cardiovascular and thrombotic disease.
Collapse
Affiliation(s)
- Jared S Elenbaas
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA.
- Medical Scientist Training Program, Washington University School of Medicine, Saint Louis, MO, 63110, USA.
| | - Upasana Pudupakkam
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Katrina J Ashworth
- Division of Pediatric Hematology Oncology, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Chul Joo Kang
- McDonnell Genome Institute, Washington University School of Medicine, Saint Louis, MO, 63108, USA
| | - Ved Patel
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Katherine Santana
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - In-Hyuk Jung
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Paul C Lee
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
- Medical Scientist Training Program, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Kendall H Burks
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
- Medical Scientist Training Program, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Junedh M Amrute
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
- Medical Scientist Training Program, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Robert P Mecham
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Carmen M Halabi
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA
- Department of Pediatrics, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Arturo Alisio
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Jorge Di Paola
- Division of Pediatric Hematology Oncology, Washington University in St. Louis, St. Louis, MO, 63110, USA
| | - Nathan O Stitziel
- Division of Cardiology, Department of Medicine, Washington University School of Medicine, Saint Louis, MO, 63110, USA.
- McDonnell Genome Institute, Washington University School of Medicine, Saint Louis, MO, 63108, USA.
- Department of Genetics, Washington University School of Medicine, Saint Louis, MO, 63110, USA.
| |
Collapse
|
5
|
Ferreira JJ, Amazu C, Puga-Molina LC, Ma X, England SK, Santi CM. SLO2.1/NALCN a sodium signaling complex that regulates uterine activity. iScience 2021; 24:103210. [PMID: 34746693 PMCID: PMC8551532 DOI: 10.1016/j.isci.2021.103210] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 07/29/2021] [Accepted: 09/29/2021] [Indexed: 01/05/2023] Open
Abstract
Depolarization of the myometrial smooth muscle cell (MSMC) resting membrane potential is necessary for the uterus to transition from a quiescent state to a contractile state. The molecular mechanisms involved in this transition are not completely understood. Here, we report that a coupled system between the Na+-activated K+ channel (SLO2.1) and the non-selective Na+ leak channel (NALCN) determines the MSMC membrane potential. Our data indicate that Na+ entering through NALCN acts as an intracellular signaling molecule that activates SLO2.1. Potassium efflux through SLO2.1 hyperpolarizes the membrane. A decrease in SLO2.1/NALCN activity induces membrane depolarization, triggering Ca2+ entry through voltage-dependent Ca2+ channels and promoting contraction. Consistent with functional coupling, our data show that NALCN and SLO2.1 are in close proximity in human MSMCs. We propose that these arrangements of SLO2.1 and NALCN permit these channels to functionally regulate MSMC membrane potential and cell excitability and modulate uterine contractility.
Collapse
Affiliation(s)
- Juan J. Ferreira
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, St. Louis, MO 63110, USA
| | - Chinwendu Amazu
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Lis C. Puga-Molina
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Xiaofeng Ma
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Sarah K. England
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
| | - Celia M. Santi
- Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, Washington University in St. Louis, School of Medicine, 425 S. Euclid Avenue, CB 8064, St. Louis, MO 63110, USA
- Department of Neuroscience, Washington University in St. Louis, School of Medicine, St. Louis, MO 63110, USA
| |
Collapse
|
6
|
Cole BA, Clapcote SJ, Muench SP, Lippiat JD. Targeting K Na1.1 channels in KCNT1-associated epilepsy. Trends Pharmacol Sci 2021; 42:700-713. [PMID: 34074526 DOI: 10.1016/j.tips.2021.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 04/30/2021] [Accepted: 05/05/2021] [Indexed: 12/19/2022]
Abstract
Gain-of-function (GOF) pathogenic variants of KCNT1, the gene encoding the largest known potassium channel subunit, KNa1.1, are associated with developmental and epileptic encephalopathies accompanied by severe psychomotor and intellectual disabilities. Blocking hyperexcitable KNa1.1 channels with quinidine, a class I antiarrhythmic drug, has shown variable success in patients in part because of dose-limiting off-target effects, poor blood-brain barrier (BBB) penetration, and low potency. In recent years, high-resolution cryogenic electron microscopy (cryo-EM) structures of the chicken KNa1.1 channel in different activation states have been determined, and animal models of the diseases have been generated. Alongside increasing information about the functional effects of GOF pathogenic variants on KNa1.1 channel behaviour and how they lead to hyperexcitability, these tools will facilitate the development of more effective treatment strategies. We review the range of KCNT1 variants and their functional effects, the challenges posed by current treatment strategies, and recent advances in finding more potent and selective therapeutic interventions for KCNT1-related epilepsies.
Collapse
Affiliation(s)
- Bethan A Cole
- School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Steven J Clapcote
- School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Stephen P Muench
- School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK
| | | |
Collapse
|
7
|
Ikeda A, Ueda H, Matsui K, Iai M, Goto T. Recurrent pulmonary hemorrhage in juvenile patients with KCNT1 mutation. Pediatr Int 2021; 63:352-354. [PMID: 33650128 DOI: 10.1111/ped.14427] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/15/2020] [Accepted: 07/28/2020] [Indexed: 02/01/2023]
Affiliation(s)
- Azusa Ikeda
- Department of Neurology, Kanagawa Children's Medical Center, Yokohama, Japan
| | - Hideaki Ueda
- Department of Cardiology, Kanagawa Children's Medical Center, Yokohama, Japan
| | - Kiyoshi Matsui
- Division of General Medicine, Kanagawa Children's Medical Center, Yokohama, Japan
| | - Mizue Iai
- Department of Neurology, Kanagawa Children's Medical Center, Yokohama, Japan
| | - Tomohide Goto
- Department of Neurology, Kanagawa Children's Medical Center, Yokohama, Japan
| |
Collapse
|