51
|
Yunaini L, Erlina L, Fadilah F, Pujianto DA. In silico docking analysis of beta-defensin 20 against cation channel sperm-associated protein 1-4 to predict its role in the sperm maturation. Asian J Androl 2023; 25:528-532. [PMID: 36571327 PMCID: PMC10411257 DOI: 10.4103/aja2022103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 11/16/2022] [Indexed: 12/27/2022] Open
Abstract
Beta-defensin 20 (DEFB20) is widely expressed in the epididymis with gene features involved in epididymal sperm maturation. However, the action mechanism and function of DEFB20 in sperm maturation are still unclear. One of the important roles of beta-defensin is the ion channel activity. The cation channel sperm-associated protein (CatSper) alpha is an ion channel protein found on the sperm surface. This study aimed to investigate the interaction between DEFB20 and CatSper1-4 protein in relation to the sperm maturation process. Protein sequences were obtained from the National Center for Biotechnology Information (NCBI). Protein modeling and validation were carried out by using the Robetta modeling server and the Ramachandran plot method. Rosetta web server was used for the docking analysis. The results revealed a natural interaction between DEFB20 and CatSper1-4. The interaction occurred at the cation channel (close to the casein kinase II), ion transport protein, and kinase c phosphorylation of the CatSper1-4 active site. The DEFB20 region interacting with CatSper2-4 was the beta-defensin domain, while with CatSper1 was the non-beta-defensin domain. Based on the analysis, DEFB20 may interact with CatSper α subunits, particularly CatsSper1, to affect ion channel activity during sperm maturation.
Collapse
Affiliation(s)
- Luluk Yunaini
- Doctoral Program for Biomedical Sciences, Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
- Department of Medical Biology, Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
| | - Linda Erlina
- Department of Medical Chemistry, Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
- Bioinformatics Core Facilities, Indonesia Medical Education and Research Institute (IMERI), Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
| | - Fadilah Fadilah
- Department of Medical Chemistry, Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
- Bioinformatics Core Facilities, Indonesia Medical Education and Research Institute (IMERI), Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
| | - Dwi Ari Pujianto
- Department of Medical Biology, Faculty of Medicine, Universitas Indonesia, Jakarta 10430, Indonesia
| |
Collapse
|
52
|
Nawaly H, Matsui H, Tsuji Y, Iwayama K, Ohashi H, Nakajima K, Matsuda Y. Multiple plasma membrane SLC4s contribute to external HCO3- acquisition during CO2 starvation in the marine diatom Phaeodactylum tricornutum. J Exp Bot 2023; 74:296-307. [PMID: 36124754 DOI: 10.1093/jxb/erac380] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 09/16/2022] [Indexed: 06/15/2023]
Abstract
The availability of CO2 is one of the restrictions on aquatic photosynthesis. Solute carrier (SLC) 4-2, a plasma membrane HCO3- transporter has previously been identified in the marine diatom Phaeodactylum tricornutum. In this study, we discovered two paralogs, PtSLC4-1 and PtSLC4-4, that are both localized at the plasma membrane. Their overexpression stimulated HCO3- uptake, and this was inhibited by the anion channel blocker 4,4´-diisothiocyanostilbene-2,2´-disulfonic (DIDS). Similarly to SLC4-2, PtSLC4-1 specifically required Na+ of ~100 mM for its maximum HCO3- transport activity. Unlike PtSLC4-1 and PtSLC4-2, the HCO3- transport of PtSLC4-4 depended equally on Na+, K+, or Li+, suggesting its broad selectivity for cations. Transcript analyses indicated that PtSLC4-1 was the most abundant HCO3- transporter under CO2 concentrations below atmospheric levels, while PtSLC4-4 showed little transcript induction under atmospheric CO2 but transient induction to comparable levels to PtSLC4-1 during the initial acclimation stage from high CO2 (1%) to very low CO2 (<0.002%). Our results strongly suggest a major HCO3- transport role of PtSLC4-1 with a relatively minor role of PtSLC4-2, and that PtSLC4-4 operates under severe CO2 limitation unselectively to cations when the other SLC4s do not function to support HCO3- uptake.
Collapse
Affiliation(s)
- Hermanus Nawaly
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Hiroaki Matsui
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Yoshinori Tsuji
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
- Graduate School of Biostudies, Kyoto University, Kyoto 606-8502, Japan
| | - Kazufumi Iwayama
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Hiroki Ohashi
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Kensuke Nakajima
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| | - Yusuke Matsuda
- Department of Bioscience, School of Science and Technology, Kwansei Gakuin University, 1 Gakuen Uegahara, Sanda, Hyogo, 669-1330, Japan
| |
Collapse
|
53
|
Wu D, Xu L, Cai WM, Zhan SY, Wan G, Xu Y, Shi YS. A splicing-dependent ER retention signal regulates surface expression of the mechanosensitive TMEM63B cation channel. J Biol Chem 2022; 299:102781. [PMID: 36496074 PMCID: PMC9830214 DOI: 10.1016/j.jbc.2022.102781] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
TMEM63B is a mechanosensitive cation channel activated by hypoosmotic stress and mechanic stimulation. We recently reported a brain-specific alternative splicing of exon 4 in TMEM63B. The short variant lacking exon 4, which constitutes the major isoform in the brain, exhibits enhanced responses to hypoosmotic stimulation compared to the long isoform containing exon 4. However, the mechanisms affecting this differential response are unclear. Here, we showed that the short isoform exhibited stronger cell surface expression compared to the long variant. Using mutagenesis screening of the coding sequence of exon 4, we identified an RXR-type endoplasmic reticulum (ER) retention signal (RER). We found that this motif was responsible for binding to the COPI retrieval vesicles, such that the longer TMEM63B isoforms were more likely to be retrotranslocated to the ER than the short isoforms. In addition, we demonstrated long TMEM63Bs could form heterodimers with short isoforms and reduce their surface expression. Taken together, our findings revealed an ER retention signal in the alternative splicing domain of TMEM63B that regulates the surface expression of TMEM63B protein and channel function.
Collapse
Affiliation(s)
- Dan Wu
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China; Guangdong Institute of Intelligence Science and Technology, Zhuhai, China
| | - Lushan Xu
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China; Clinical College of Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, China
| | - Wen-Min Cai
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Shi-Yu Zhan
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Guoqiang Wan
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China; Institute for Brain Sciences, Nanjing University, Nanjing, China
| | - Yun Xu
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China; Institute for Brain Sciences, Nanjing University, Nanjing, China.
| | - Yun Stone Shi
- Department of Neurology, Drum Tower Hospital, Ministry of Education Key -Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China; Guangdong Institute of Intelligence Science and Technology, Zhuhai, China; Institute for Brain Sciences, Nanjing University, Nanjing, China.
| |
Collapse
|
54
|
Wang X, Hu L, Wang C, He B, Fu Z, Jin C, Jin Y. Cross-generational effects of maternal exposure to imazalil on anaerobic components and carnitine absorption associated with OCTN2 expression in mice. Chemosphere 2022; 308:136542. [PMID: 36150497 DOI: 10.1016/j.chemosphere.2022.136542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/23/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Imazalil (IMZ) is a fungicide recommended by the Chinese ministry of agriculture. However, recent study was observed high level of IMZ by dietary exposure in pregnant women. To determine the cross-generational effects, C57BL/6 mice were exposed to IMZ at dietary levels of 0, 0.025‰, and 0.25‰ during the gestation and lactation periods. Then, we assessed the changes in growth phenotypes, carnitine levels, and gut microbiota in F0, F1 or F2 generations. The growth phenotypes of dams didn't observe significant difference, but there were significant changes in the offspring. Plasma samples revealed low levels of free carnitine (C0), long-chain acyl-carnitines and total carnitine. In particular, C0 may be regarded as relatively potential, specific markers by maternal IMZ exposure. Caco2 cell culture and animal experiment confirmed IMZ affected carnitine absorption through the organic cation transporter type-2 (OCTN2) protein encoded by solute carrier family 22A member 5 (SLC22A5) gene in colon. Maternal IMZ exposure also had a greater effect on gut microbiota in offspring, especially anaerobic bacteria, which positively correlated with C0 and acyl-carnitines. These results suggested that maternal IMZ exposure affected carnitine absorption through OCTN2 protein, which led to the decline of anaerobic bacteria and unbalanced intestinal homeostasis.
Collapse
Affiliation(s)
- Xiaofang Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Lingyu Hu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Caiyun Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Bingnan He
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Zhengwei Fu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Cuiyuan Jin
- Institute of Translational Medicine, Zhejiang Shuren University, Hangzhou, 310015, China.
| | - Yuanxiang Jin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310032, China.
| |
Collapse
|
55
|
Hennaux L, Kohchtali A, Bâlon H, Matroule JY, Michaux C, Perpète EA. Refolding and biophysical characterization of the Caulobacter crescentus copper resistance protein, PcoB: An outer membrane protein containing an intrinsically disordered domain. Biochim Biophys Acta Biomembr 2022; 1864:184038. [PMID: 36057369 DOI: 10.1016/j.bbamem.2022.184038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 08/16/2022] [Accepted: 08/25/2022] [Indexed: 06/15/2023]
Abstract
Copper cations play fundamental roles in biological systems, such as protein folding and stabilization, or enzymatic reactions. Although copper is essential to the cell, it can become cytotoxic if present in too high concentration. Organisms have therefore developed specific regulation mechanisms towards copper. This is the case of the Pco system present in the bacterium Caulobacter crescentus, which is composed of two proteins: a soluble periplasmic protein PcoA and an outer membrane protein PcoB. PcoA oxidizes Cu+ to Cu2+, whereas PcoB is thought to be an efflux pump for Cu2+. While the PcoA protein has already been studied, very little is known about the structure and function of PcoB. In the present work, PcoB has been overexpressed in high yield in E. coli strains and successfully refolded by the SDS-cosolvent method. Binding to divalent cations has also been studied using several spectroscopic techniques. In addition, a three-dimensional structure model of PcoB, experimentally supported by circular dichroism, has been constructed, showing a β-barrel conformation with a N-terminal disordered chain. This peculiar intrinsic disorder property has also been confirmed by various bioinformatic tools.
Collapse
Affiliation(s)
- Laurelenn Hennaux
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium; Namur Institute of Structured Matter (NISM), University of Namur, Namur, Belgium; Namur Research Institute for Life Sciences (NARILIS), University of Namur, Namur, Belgium.
| | - Amira Kohchtali
- Research Unit in Microorganisms Biology (URBM), Department of Biology, Namur, Belgium; Namur Research Institute for Life Sciences (NARILIS), University of Namur, Namur, Belgium
| | - Hugo Bâlon
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium
| | - Jean-Yves Matroule
- Research Unit in Microorganisms Biology (URBM), Department of Biology, Namur, Belgium; Namur Research Institute for Life Sciences (NARILIS), University of Namur, Namur, Belgium
| | - Catherine Michaux
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium; Namur Institute of Structured Matter (NISM), University of Namur, Namur, Belgium; Namur Research Institute for Life Sciences (NARILIS), University of Namur, Namur, Belgium
| | - Eric A Perpète
- Laboratoire de Chimie Physique des Biomolécules, UCPTS, University of Namur, 61 rue de Bruxelles, 5000 Namur, Belgium; Namur Institute of Structured Matter (NISM), University of Namur, Namur, Belgium; Institute of Life-Earth-Environment (ILEE), University of Namur, Namur, Belgium
| |
Collapse
|
56
|
He J, Yang B, Hause G, Rössner N, Peiter-Volk T, Schattat MH, Voiniciuc C, Peiter E. The trans-Golgi-localized protein BICAT3 regulates manganese allocation and matrix polysaccharide biosynthesis. Plant Physiol 2022; 190:2579-2600. [PMID: 35993897 PMCID: PMC9706472 DOI: 10.1093/plphys/kiac387] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 07/18/2022] [Indexed: 05/11/2023]
Abstract
Manganese (Mn2+) is essential for a diversity of processes, including photosynthetic water splitting and the transfer of glycosyl moieties. Various Golgi-localized glycosyltransferases that mediate cell wall matrix polysaccharide biosynthesis are Mn2+ dependent, but the supply of these enzymes with Mn2+ is not well understood. Here, we show that the BIVALENT CATION TRANSPORTER 3 (BICAT3) localizes specifically to trans-cisternae of the Golgi. In agreement with a role in Mn2+ and Ca2+ homeostasis, BICAT3 rescued yeast (Saccharomyces cerevisiae) mutants defective in their translocation. Arabidopsis (Arabidopsis thaliana) knockout mutants of BICAT3 were sensitive to low Mn2+ and high Ca2+ availability and showed altered accumulation of these cations. Despite reduced cell expansion and leaf size in Mn2+-deficient bicat3 mutants, their photosynthesis was improved, accompanied by an increased Mn content of chloroplasts. Growth defects of bicat3 corresponded with an impaired glycosidic composition of matrix polysaccharides synthesized in the trans-Golgi. In addition to the vegetative growth defects, pollen tube growth of bicat3 was heterogeneously aberrant. This was associated with a severely reduced and similarly heterogeneous pectin deposition and caused diminished seed set and silique length. Double mutant analyses demonstrated that the physiological relevance of BICAT3 is distinct from that of ER-TYPE CA2+-ATPASE 3, a Golgi-localized Mn2+/Ca2+-ATPase. Collectively, BICAT3 is a principal Mn2+ transporter in the trans-Golgi whose activity is critical for specific glycosylation reactions in this organelle and for the allocation of Mn2+ between Golgi apparatus and chloroplasts.
Collapse
Affiliation(s)
- Jie He
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Bo Yang
- Independent Junior Research Group—Designer Glycans, Leibniz Institute of Plant Biochemistry, Halle (Saale), 06120, Germany
| | - Gerd Hause
- Biocentre, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Nico Rössner
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Tina Peiter-Volk
- Plant Nutrition Laboratory, Institute of Agricultural and Nutritional Sciences, Faculty of Natural Sciences III, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Martin H Schattat
- Plant Physiology, Institute of Biology, Faculty of Natural Sciences I, Martin Luther University Halle-Wittenberg, Halle (Saale), 06120, Germany
| | - Cătălin Voiniciuc
- Independent Junior Research Group—Designer Glycans, Leibniz Institute of Plant Biochemistry, Halle (Saale), 06120, Germany
- Horticultural Sciences Department, University of Florida, Gainesville, Florida 32611, USA
| | | |
Collapse
|
57
|
Redeker KEM, Jensen O, Gebauer L, Meyer-Tönnies MJ, Brockmöller J. Atypical Substrates of the Organic Cation Transporter 1. Biomolecules 2022; 12:1664. [PMID: 36359014 PMCID: PMC9687798 DOI: 10.3390/biom12111664] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 10/27/2022] [Accepted: 11/02/2022] [Indexed: 10/29/2023] Open
Abstract
The human organic cation transporter 1 (OCT1) is expressed in the liver and mediates hepatocellular uptake of organic cations. However, some studies have indicated that OCT1 could transport neutral or even anionic substrates. This capability is interesting concerning protein-substrate interactions and the clinical relevance of OCT1. To better understand the transport of neutral, anionic, or zwitterionic substrates, we used HEK293 cells overexpressing wild-type OCT1 and a variant in which we changed the putative substrate binding site (aspartate474) to a neutral amino acid. The uncharged drugs trimethoprim, lamivudine, and emtricitabine were good substrates of hOCT1. However, the uncharged drugs zalcitabine and lamotrigine, and the anionic levofloxacin, and prostaglandins E2 and F2α, were transported with lower activity. Finally, we could detect only extremely weak transport rates of acyclovir, ganciclovir, and stachydrine. Deleting aspartate474 had a similar transport-lowering effect on anionic substrates as on cationic substrates, indicating that aspartate474 might be relevant for intra-protein, rather than substrate-protein, interactions. Cellular uptake of the atypical substrates by the naturally occurring frequent variants OCT1*2 (methionine420del) and OCT1*3 (arginine61cysteine) was similarly reduced, as it is known for typical organic cations. Thus, to comprehensively understand the substrate spectrum and transport mechanisms of OCT1, one should also look at organic anions.
Collapse
Affiliation(s)
- Kyra-Elisa Maria Redeker
- Institute of Clinical Pharmacology, University Medical Centre Göttingen, 37075 Göttingen, Germany
| | - Ole Jensen
- Institute of Clinical Pharmacology, University Medical Centre Göttingen, 37075 Göttingen, Germany
| | - Lukas Gebauer
- Institute of Clinical Pharmacology, University Medical Centre Göttingen, 37075 Göttingen, Germany
| | - Marleen Julia Meyer-Tönnies
- Department of General Pharmacology, Institute of Pharmacology, Centre of Drug Absorption and Transport (C-DAT), University Medical Centre Greifswald, 17487 Greifswald, Germany
| | - Jürgen Brockmöller
- Institute of Clinical Pharmacology, University Medical Centre Göttingen, 37075 Göttingen, Germany
| |
Collapse
|
58
|
Li Y, Li YL, Liu YL, Fu J, Zhang WW, Piao YS. [Expression of cation chloride cotransporter (NKCC1/KCC2) in brain tissue of children with focal cortical dysplasia type Ⅱ]. Zhonghua Bing Li Xue Za Zhi 2022; 51:1123-1128. [PMID: 36323541 DOI: 10.3760/cma.j.cn112151-20220418-00300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To investigate the expression of cation chloride cotransporter (NKCC1/KCC2) in the neurons from cerebral lesions of children with focal cortical dysplasia (FCD) type Ⅱ, to provide a morphological basis for revealing the possible mechanism of epilepsy. Methods: Eight cases of FCD type Ⅱ diagnosed at Beijing Haidian Hospital, Beijing, China and 12 cases diagnosed at Xuanwu Hospital, Capital Medical University, Beijing, China from February 2017 to December 2019 were included. The expression of NKCC1 and KCC2 in FCD type Ⅱa and FCD type Ⅱb was detected using immunohistochemistry and double immunohistochemical stains. The average optical density of NKCC1 in dysmorphic neurons and normal neurons was also determined using immunohistochemical staining in FCD type Ⅱa (10 cases). Results: The patients were all younger than 14 years of age. Ten cases were classified as FCD type IIa, and 10 cases as FCD type Ⅱb. NKCC1 was expressed in the cytoplasm of normal cerebral cortex neurons and KCC2 expressed on cell membranes. In dysmorphic neurons of FCD type Ⅱa, expression of NKCC1 increased, which was statistically higher than that of normal neurons (P<0.01). Aberrant expression of KCC2 in dysmorphic neurons was also noted in the cytoplasm. In the FCD Ⅱb type, the expression pattern of NKCC1/KCC2 in dysmorphic neurons was the same as that of FCD type Ⅱa. The aberrant expression of NKCC1 in balloon cells was negative or weakly positive on the cell membrane, while the aberrant expression of KCC2 was absent. Conclusions: The expression pattern of NKCC1/KCC2 in dysmorphic neurons and balloon cells is completely different from that of normal neurons. The NKCC1/KCC2 protein-expression changes may affect the transmembrane chloride flow of neurons, modify the effect of inhibitory neurotransmitters γ-aminobutyric acid and increase neuronal excitability. These effects may be related to the occurrence of clinical epileptic symptoms.
Collapse
Affiliation(s)
- Y Li
- Department of Pathology, Beijing Haidian Hospital/Peking University Third Hospital Haidian Division, Beijing 100080, China
| | - Y L Li
- Department of Neurosurgery, Capital Institute of Pediatrics, Beijing 100020, China
| | - Y L Liu
- Department of Pathology, Beijing Haidian Hospital/Peking University Third Hospital Haidian Division, Beijing 100080, China
| | - J Fu
- Department of Pathology, Beijing Haidian Hospital/Peking University Third Hospital Haidian Division, Beijing 100080, China
| | - W W Zhang
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Y S Piao
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| |
Collapse
|
59
|
Valsecchi WM, Faraj SE, Cerf NT, Fedosova NU, Montes MR. The transported cations impose differences in the thermostability of the gastric H,K-ATPase. A kinetic analysis. Biochim Biophys Acta Biomembr 2022; 1864:184006. [PMID: 35868405 DOI: 10.1016/j.bbamem.2022.184006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 07/06/2022] [Accepted: 07/12/2022] [Indexed: 06/15/2023]
Abstract
This work analyses the thermostability of a membrane protein, the gastric H,K-ATPase, by means of a detailed kinetic characterization of its inactivation process, which showed to exhibit first-order kinetics. We observed parallel time courses for the decrease of ATPase activity, the decrease of the autophosphorylation capacity and the loss of tertiary structure at 49 °C. Higher temperatures were required to induce a significant change in secondary structure. The correspondence between the kinetics of Trp fluorescence measured at 49 °C and the decrease of the residual activity after heating at that temperature, proves the irreversibility of the inactivation process. Inactivation proceeds at different rates in E1 or E2 conformations. The K+-induced E2 state exhibits a lower inactivation rate; the specific effect is exerted with a K0.5 similar to that found at 25 °C, providing a further inkling that K+ occlusion by the H,K-ATPase is not really favoured. Increasing [H+] from pH 8 to pH 7, which possibly shifts the protein to E1, produces a subtle destabilizing effect on the H,K-ATPase. We performed a prediction of potential intramolecular interactions and found that the differential stability between E1 and E2 may be mainly explained by the higher number of hydrophobic interactions in the α- and β-subunits of E2 conformation.
Collapse
Affiliation(s)
- W M Valsecchi
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas "Prof. Alejandro C. Paladini" (IQUIFIB), Buenos Aires, Argentina
| | - S E Faraj
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas "Prof. Alejandro C. Paladini" (IQUIFIB), Buenos Aires, Argentina
| | - N T Cerf
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas "Prof. Alejandro C. Paladini" (IQUIFIB), Buenos Aires, Argentina
| | - N U Fedosova
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - M R Montes
- Universidad de Buenos Aires, Facultad de Farmacia y Bioquímica, Departamento de Química Biológica, Buenos Aires, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad de Buenos Aires, Instituto de Química y Fisicoquímica Biológicas "Prof. Alejandro C. Paladini" (IQUIFIB), Buenos Aires, Argentina.
| |
Collapse
|
60
|
Mohring F, van Schalkwyk DA, Henrici RC, Blasco B, Leroy D, Sutherland CJ, Moon RW. Cation ATPase (ATP4) Orthologue Replacement in the Malaria Parasite Plasmodium knowlesi Reveals Species-Specific Responses to ATP4-Targeting Drugs. mBio 2022; 13:e0117822. [PMID: 36190127 PMCID: PMC9600963 DOI: 10.1128/mbio.01178-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 08/31/2022] [Indexed: 11/30/2022] Open
Abstract
Several unrelated classes of antimalarial compounds developed against Plasmodium falciparum target a parasite-specific P-type ATP-dependent Na+ pump, PfATP4. We have previously shown that other malaria parasite species infecting humans are less susceptible to these compounds. Here, we generated a series of transgenic Plasmodium knowlesi orthologue replacement (OR) lines in which the endogenous pkatp4 locus was replaced by a recodonized P. knowlesi atp4 (pkatp4) coding region or the orthologous coding region from P. falciparum, Plasmodium malariae, Plasmodium ovale subsp. curtisi, or Plasmodium vivax. Each OR transgenic line displayed a similar growth pattern to the parental P. knowlesi line. We found significant orthologue-specific differences in parasite susceptibility to three chemically unrelated ATP4 inhibitors, but not to comparator drugs, among the P. knowlesi OR lines. The PfATP4OR transgenic line of P. knowlesi was significantly more susceptible than our control PkATP4OR line to three ATP4 inhibitors: cipargamin, PA21A092, and SJ733. The PvATP4OR and PmATP4OR lines were similarly susceptible to the control PkATP4OR line, but the PocATP4OR line was significantly less susceptible to all ATP4 inhibitors than the PkATP4OR line. Cipargamin-induced inhibition of Na+ efflux was also significantly greater with the P. falciparum orthologue of ATP4. This confirms that species-specific susceptibility differences previously observed in ex vivo studies of human isolates are partly or wholly enshrined in the primary amino acid sequences of the respective ATP4 orthologues and highlights the need to monitor efficacy of investigational malaria drugs against multiple species. P. knowlesi is now established as an important in vitro model for studying drug susceptibility in non-falciparum malaria parasites. IMPORTANCE Effective drugs are vital to minimize the illness and death caused by malaria. Development of new drugs becomes ever more urgent as drug resistance emerges. Among promising compounds now being developed to treat malaria are several unrelated molecules that each inhibit the same protein in the malaria parasite-ATP4. Here, we exploited the genetic tractability of P. knowlesi to replace its own ATP4 genes with orthologues from five human-infective species to understand the drug susceptibility differences among these parasites. We previously estimated the susceptibility to ATP4-targeting drugs of each species using clinical samples from malaria patients. These estimates closely matched those of the corresponding "hybrid" P. knowlesi parasites carrying introduced ATP4 genes. Thus, species-specific ATP4 inhibitor efficacy is directly determined by the sequence of the gene. Our novel approach to understanding cross-species susceptibility/resistance can strongly support the effort to develop antimalarials that effectively target all human malaria parasite species.
Collapse
Affiliation(s)
- Franziska Mohring
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Donelly A. van Schalkwyk
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Ryan C. Henrici
- Center for Global Health, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
| | | | - Didier Leroy
- Medicines for Malaria Venture, Geneva, Switzerland
| | - Colin J. Sutherland
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- UK Health Security Agency Malaria Reference Laboratory, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Robert W. Moon
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| |
Collapse
|
61
|
Sokabe T, Bradshaw HB, Tominaga M, Leishman E, Chandel A, Montell C. Endocannabinoids produced in photoreceptor cells in response to light activate Drosophila TRP channels. Sci Signal 2022; 15:eabl6179. [PMID: 36219683 PMCID: PMC9633101 DOI: 10.1126/scisignal.abl6179] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Drosophila phototransduction is a model for signaling cascades that culminate in the activation of transient receptor potential (TRP) cation channels. TRP and TRPL are the canonical TRP (TRPC) channels that are regulated by light stimulation of rhodopsin and engagement of Gαq and phospholipase Cβ (PLC). Lipid metabolite(s) generated downstream of PLC are essential for the activation of the TRPC channels in photoreceptor cells. We sought to identify the key lipids produced subsequent to PLC stimulation that contribute to channel activation. Here, using genetics, lipid analysis, and Ca2+ imaging, we found that light increased the amount of an abundant endocannabinoid, 2-linoleoyl glycerol (2-LG), in vivo. The increase in 2-LG amounts depended on the PLC and diacylglycerol lipase encoded by norpA and inaE, respectively. This endocannabinoid facilitated TRPC-dependent Ca2+ influx in a heterologous expression system and in dissociated ommatidia from compound eyes. Moreover, 2-LG and mechanical stimulation cooperatively activated TRPC channels in ommatidia. We propose that 2-LG is a physiologically relevant endocannabinoid that activates TRPC channels in photoreceptor cells.
Collapse
Affiliation(s)
- Takaaki Sokabe
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara; California 93106, USA
- Division of Cell Signaling, National Institute for Physiological Sciences, and Thermal Biology Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences; Okazaki, Aichi, 444-8787, Japan
- Department of Physiological Sciences, SOKENDAI; Okazaki, Aichi, 444-8787, Japan
| | - Heather B. Bradshaw
- Department of Psychological and Brain Sciences, Indiana University; Bloomington, Indiana, 47405, USA
| | - Makoto Tominaga
- Division of Cell Signaling, National Institute for Physiological Sciences, and Thermal Biology Group, Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences; Okazaki, Aichi, 444-8787, Japan
- Department of Physiological Sciences, SOKENDAI; Okazaki, Aichi, 444-8787, Japan
| | - Emma Leishman
- Department of Psychological and Brain Sciences, Indiana University; Bloomington, Indiana, 47405, USA
| | - Avinash Chandel
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara; California 93106, USA
| | - Craig Montell
- Department of Molecular, Cellular, and Developmental Biology and the Neuroscience Research Institute, University of California, Santa Barbara; California 93106, USA
| |
Collapse
|
62
|
Zhang J, Kong FY, Lu SG. [Remediation Effect and Mechanism of Inorganic Passivators on Cadmium Contaminated Acidic Paddy Soil]. Huan Jing Ke Xue 2022; 43:4679-4686. [PMID: 36224153 DOI: 10.13227/j.hjkx.202112273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Cadmium (Cd) is one of the main pollutants in acidic paddy fields, and its accumulation in rice (Oryza sativa L.) and subsequent transfer to the food chain is an important environmental issue in China. In our field study, three types of inorganic passivators (silicon-calcium-magnesium-potassium fertilizer (SCMK), calcium magnesium phosphate fertilizer (CMP), and lime (L) at the rate of 750, 1500, and 2250 kg·hm-2, respectively) were applied to acidic paddy soils polluted by the heavy metal Cd in southern Zhejiang province. The objective of this study was to reveal the effects and chemical mechanisms of passivators on soil acidification and Cd accumulation in rice. The field experimental results showed that the three passivators could effectively improve soil acidification and reduce Cd accumulation in rice grains. The application of 2250 kg·hm-2 SCMK, CMP, and L increased soil pH by 0.62, 0.65, and 0.86 units; decreased exchangeable acidity by 67%, 69%, and 78%; and reduced the content of Cd in brown rice by 73%, 68%, and 77%, respectively. The application of 2250 kg·hm-2 SCMK, CMP, and L reduced the content of Cd in brown rice planted on polluted paddy rice fields to lower than 0.2 mg·kg-1, which reached the national food safety standard. Compared with the control, the application of SCMK, CMP, and L significantly (P<0.05) decreased the content of available Cd extracted by DTPA; decreased the contents of weak acid-extractable (F1) and reducible (F2) Cd; and increased the content of residual (F4) Cd. Correlation analyses indicated that Cd content in brown rice was significantly negatively correlated with soil pH and exchangeable cation content and significantly positively correlated with DTPA-Cd, weak acid-extractable (F1) and reducible (F2) Cd, and exchangeable Al contents. The partial least squares path model (PLS-PM) was used to analyze the relationship between the Cd content of brown rice, DTPA-Cd, and various chemical forms of Cd and soil properties. The direct path coefficients of soil exchangeable cations on Cd content in brown rice, available cadmium, and rice yield were -0.566, -0.866, and 0.873, respectively. Soil pH indirectly affected Cd content of brown rice mainly by directly affecting available Cd in soil. Field experiments demonstrated that the three passivators SCMK, CMP, and L were effective technologies for the safe production of rice in acidic paddy soils polluted by Cd. The possible mechanism for passivators reducing the bioavailability of Cd in soil and its accumulation in brown rice contributed to increased exchangeable cations in the soils. These findings could provide a scientific basis for the safe production of rice in acidic paddy soil polluted by heavy metals.
Collapse
Affiliation(s)
- Jian Zhang
- Wenzhou Plant Protection and Soil Fertilizer Management Station, Zhejiang Province, Wenzhou 325000, China
| | - Fan-Yi Kong
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Sheng-Gao Lu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| |
Collapse
|
63
|
Holmes AOM, Goldman A, Kalli AC. mPPases create a conserved anionic membrane fingerprint as identified via multi-scale simulations. PLoS Comput Biol 2022; 18:e1010578. [PMID: 36191052 PMCID: PMC9560603 DOI: 10.1371/journal.pcbi.1010578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 10/13/2022] [Accepted: 09/16/2022] [Indexed: 11/06/2022] Open
Abstract
Membrane-integral pyrophosphatases (mPPases) are membrane-bound enzymes responsible for hydrolysing inorganic pyrophosphate and translocating a cation across the membrane. Their function is essential for the infectivity of clinically relevant protozoan parasites and plant maturation. Recent developments have indicated that their mechanism is more complicated than previously thought and that the membrane environment may be important for their function. In this work, we use multiscale molecular dynamics simulations to demonstrate for the first time that mPPases form specific anionic lipid interactions at 4 sites at the distal and interfacial regions of the protein. These interactions are conserved in simulations of the mPPases from Thermotoga maritima, Vigna radiata and Clostridium leptum and characterised by interactions with positive residues on helices 1, 2, 3 and 4 for the distal site, or 9, 10, 13 and 14 for the interfacial site. Due to the importance of these helices in protein stability and function, these lipid interactions may play a crucial role in the mPPase mechanism and enable future structural and functional studies.
Collapse
Affiliation(s)
- Alexandra O. M. Holmes
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
| | - Adrian Goldman
- School of Biomedical Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom
- Research Program in Molecular and Integrative Biosciences, University of Helsinki, Helsinki, Finland
| | - Antreas C. Kalli
- Leeds Institute of Cardiovascular and Metabolic Medicine and Astbury Centre for Structural Biology, University of Leeds, Leeds, United Kingdom
- * E-mail:
| |
Collapse
|
64
|
Zhao T, Parmisano S, Soroureddin Z, Zhao M, Yung L, Thistlethwaite PA, Makino A, Yuan JXJ. Mechanosensitive cation currents through TRPC6 and Piezo1 channels in human pulmonary arterial endothelial cells. Am J Physiol Cell Physiol 2022; 323:C959-C973. [PMID: 35968892 PMCID: PMC9485000 DOI: 10.1152/ajpcell.00313.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/09/2022] [Accepted: 08/09/2022] [Indexed: 11/22/2022]
Abstract
Mechanosensitive cation channels and Ca2+ influx through these channels play an important role in the regulation of endothelial cell functions. Transient receptor potential canonical channel 6 (TRPC6) is a diacylglycerol-sensitive nonselective cation channel that forms receptor-operated Ca2+ channels in a variety of cell types. Piezo1 is a mechanosensitive cation channel activated by membrane stretch and shear stress in lung endothelial cells. In this study, we report that TRPC6 and Piezo1 channels both contribute to membrane stretch-mediated cation currents and Ca2+ influx or increase in cytosolic-free Ca2+ concentration ([Ca2+]cyt) in human pulmonary arterial endothelial cells (PAECs). The membrane stretch-mediated cation currents and increase in [Ca2+]cyt in human PAECs were significantly decreased by GsMTX4, a blocker of Piezo1 channels, and by BI-749327, a selective blocker of TRPC6 channels. Extracellular application of 1-oleoyl-2-acetyl-sn-glycerol (OAG), a membrane permeable analog of diacylglycerol, rapidly induced whole cell cation currents and increased [Ca2+]cyt in human PAECs and human embryonic kidney (HEK)-cells transiently transfected with the human TRPC6 gene. Furthermore, membrane stretch with hypo-osmotic or hypotonic solution enhances the cation currents in TRPC6-transfected HEK cells. In HEK cells transfected with the Piezo1 gene, however, OAG had little effect on the cation currents, but membrane stretch significantly enhanced the cation currents. These data indicate that, while both TRPC6 and Piezo1 are involved in generating mechanosensitive cation currents and increases in [Ca2+]cyt in human PAECs undergoing mechanical stimulation, only TRPC6 (but not Piezo1) is sensitive to the second messenger diacylglycerol. Selective blockers of these channels may help develop novel therapies for mechanotransduction-associated pulmonary vascular remodeling in patients with pulmonary arterial hypertension.
Collapse
Affiliation(s)
- Tengteng Zhao
- Section of Physiology, Division of Pulmonary, Critical Care and Sleep Medicine, University of California, San Diego, California
| | - Sophia Parmisano
- Section of Physiology, Division of Pulmonary, Critical Care and Sleep Medicine, University of California, San Diego, California
| | - Zahra Soroureddin
- Section of Physiology, Division of Pulmonary, Critical Care and Sleep Medicine, University of California, San Diego, California
| | - Manjia Zhao
- Section of Physiology, Division of Pulmonary, Critical Care and Sleep Medicine, University of California, San Diego, California
| | - Lauren Yung
- Section of Physiology, Division of Pulmonary, Critical Care and Sleep Medicine, University of California, San Diego, California
| | - Patricia A Thistlethwaite
- Division of Cardiothoracic Surgery, Department of Surgery, University of California, San Diego, California
| | - Ayako Makino
- Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Diego, California
| | - Jason X-J Yuan
- Section of Physiology, Division of Pulmonary, Critical Care and Sleep Medicine, University of California, San Diego, California
| |
Collapse
|
65
|
Routh BN, Brager DH, Johnston D. Ionic and morphological contributions to the variable gain of membrane responses in layer 2/3 pyramidal neurons of mouse primary visual cortex. J Neurophysiol 2022; 128:1040-1050. [PMID: 36129187 PMCID: PMC9576169 DOI: 10.1152/jn.00181.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 09/12/2022] [Accepted: 09/13/2022] [Indexed: 11/22/2022] Open
Abstract
Many neuronal cell types exhibit a sliding scale of neuronal excitability in the subthreshold voltage range. This is due to a variable contribution of different voltage-gated ion channels, leading to scaling of input resistance (RN) as a function of membrane potential (Vm) and a voltage-dependent dynamic gain of neuronal responsiveness. In layer 2/3 pyramidal neurons within the primary visual cortex (V1), this response influences sensory processing by tightening neuronal tuning to preferred orientations, but the identity of the ionic conductances involved remains unknown. Here, we used in vitro physiological recordings in acute slices to identify the contributions of several voltage-dependent conductances to the dynamic gain of membrane responses in layer 2/3 pyramidal neurons in mouse primary visual cortex. We found that the steep voltage dependence of input resistance in these cells was mediated in part by a combination of persistent sodium, inwardly rectifying potassium, and hyperpolarization-activated nonselective cation channels. In addition, the steepness of the slope of the RN/Vm relationship was inversely correlated with the number of branches on the proximal apical dendrite. These data have uncovered physiological and morphological factors that underlie the scaling of membrane responses in L2/3 neurons of rodent V1. Regulation of these channels would serve as a mechanism of real-time neuromodulation of neuronal processing of sensory information.NEW & NOTEWORTHY Layer 2/3 pyramidal neurons in primary visual cortex scale subthreshold voltage responses with resting membrane potential because RN increases as Vm is depolarized. Here, we uncovered the voltage-dependent contributions of NaP, Kir, and HCN conductances toward this behavior, and we additionally demonstrated that the strength of the RN/Vm relationship is inversely correlated with proximal branching along the apical dendrite.
Collapse
Affiliation(s)
- Brandy N Routh
- Center for Learning and Memory, Department of Neuroscience, University of Texas at Austin, Austin, Texas
| | - Darrin H Brager
- Center for Learning and Memory, Department of Neuroscience, University of Texas at Austin, Austin, Texas
| | - Daniel Johnston
- Center for Learning and Memory, Department of Neuroscience, University of Texas at Austin, Austin, Texas
| |
Collapse
|
66
|
Förderer A, Li E, Lawson AW, Deng YN, Sun Y, Logemann E, Zhang X, Wen J, Han Z, Chang J, Chen Y, Schulze-Lefert P, Chai J. A wheat resistosome defines common principles of immune receptor channels. Nature 2022; 610:532-539. [PMID: 36163289 PMCID: PMC9581773 DOI: 10.1038/s41586-022-05231-w] [Citation(s) in RCA: 62] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 08/11/2022] [Indexed: 01/17/2023]
Abstract
Plant intracellular nucleotide-binding leucine-rich repeat receptors (NLRs) detect pathogen effectors to trigger immune responses1. Indirect recognition of a pathogen effector by the dicotyledonous Arabidopsis thaliana coiled-coil domain containing NLR (CNL) ZAR1 induces the formation of a large hetero-oligomeric protein complex, termed the ZAR1 resistosome, which functions as a calcium channel required for ZAR1-mediated immunity2-4. Whether the resistosome and channel activities are conserved among plant CNLs remains unknown. Here we report the cryo-electron microscopy structure of the wheat CNL Sr355 in complex with the effector AvrSr356 of the wheat stem rust pathogen. Direct effector binding to the leucine-rich repeats of Sr35 results in the formation of a pentameric Sr35-AvrSr35 complex, which we term the Sr35 resistosome. Wheat Sr35 and Arabidopsis ZAR1 resistosomes bear striking structural similarities, including an arginine cluster in the leucine-rich repeats domain not previously recognized as conserved, which co-occurs and forms intramolecular interactions with the 'EDVID' motif in the coiled-coil domain. Electrophysiological measurements show that the Sr35 resistosome exhibits non-selective cation channel activity. These structural insights allowed us to generate new variants of closely related wheat and barley orphan NLRs that recognize AvrSr35. Our data support the evolutionary conservation of CNL resistosomes in plants and demonstrate proof of principle for structure-based engineering of NLRs for crop improvement.
Collapse
Affiliation(s)
- Alexander Förderer
- Institute of Biochemistry, University of Cologne, Cologne, Germany
- Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Ertong Li
- Institute of Biochemistry, University of Cologne, Cologne, Germany
- Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Aaron W Lawson
- Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Ya-Nan Deng
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yue Sun
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Elke Logemann
- Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Xiaoxiao Zhang
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jie Wen
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhifu Han
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Junbiao Chang
- Henan Key Laboratory of Organic Functional Molecules and Drug Innovation, Henan Normal University, School of Pharmaceutical Sciences, Zhengzhou University, Zhengzhou, China
| | - Yuhang Chen
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China; Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China.
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China.
| | | | - Jijie Chai
- Institute of Biochemistry, University of Cologne, Cologne, Germany.
- Max Planck Institute for Plant Breeding Research, Cologne, Germany.
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, Center for Plant Biology, School of Life Sciences, Tsinghua University, Beijing, China.
| |
Collapse
|
67
|
Koumangoye R, Penny P, Delpire E. Loss of NKCC1 function increases epithelial tight junction permeability by upregulating claudin-2 expression. Am J Physiol Cell Physiol 2022; 323:C1251-C1263. [PMID: 35968893 PMCID: PMC9576170 DOI: 10.1152/ajpcell.00334.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/22/2022]
Abstract
Conditions that cause the loss of epithelial barrier integrity are often accompanied by dysregulation of tight junction protein expression and/or localization. Recently, we have reported that patients with mutations in SLC12A2, the gene encoding the basolateral Na+-K+-2Cl- cotransporter (NKCC1), suffer from severe gastrointestinal deficits, including chronic gastrointestinal inflammation, gastrointestinal hemorrhage, intestinal obstruction, and constipation. Although the intestinal inflammation observed in patients with loss of NKCC1 function may or may not be due to tight junction dysfunction, we investigated whether the loss of NKCC1 function affects paracellular ion transport and epithelial barrier function. Wild-type HT29-MTX-E12 and CRISPR/Cas9-mediated NKCC1 knockout (KO) HT29 clones were tested for tight junction protein expression and localization. Tightness of epithelial cell monolayer was assessed by measurement of transepithelial electrical resistance and permeability of molecular tracers in transwell filters. Tight junction protein localization was assessed by immunofluorescence. Loss of NKCC1 expression strongly increases the expression of claudin-2 and occludin in epithelial cell monolayers. Loss of NKCC1 significantly reduces the transepithelial electrical resistance (TER) indicating an increase in paracellular ions flux, consistent with upregulation of the cation-selective and channel-forming claudin-2. In addition, NKCC1-KO monolayers showed a significant increase in the paracellular flux of small molecules like fluorescein (0.33 kDa), whereas the permeability of higher molecular weight TRITC-Dextran (4 kDa and 70 kDa) remained unchanged. Thus, NKCC1 regulates tight junction protein expression and loss of NKCC1 function affects epithelial barrier integrity.
Collapse
Affiliation(s)
- Rainelli Koumangoye
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Parker Penny
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee
| |
Collapse
|
68
|
Abstract
Microbial channelrhodopsins are light-gated ion channels widely used for optogenetic manipulation of neuronal activity. ChRmine is a bacteriorhodopsin-like cation channelrhodopsin (BCCR) more closely related to ion pump rhodopsins than other channelrhodopsins. ChRmine displays unique properties favorable for optogenetics including high light sensitivity, a broad, red-shifted activation spectrum, cation selectivity, and large photocurrents, while its slow closing kinetics impedes some applications. The structural basis for ChRmine function, or that of any other BCCR, is unknown. Here, we present cryo-EM structures of ChRmine in lipid nanodiscs in apo (opsin) and retinal-bound (rhodopsin) forms. The structures reveal an unprecedented trimeric architecture with a lipid filled central pore. Large electronegative cavities on either side of the membrane facilitate high conductance and selectivity for cations over protons. The retinal binding pocket structure suggests channel properties could be tuned with mutations and we identify ChRmine variants with ten-fold decreased and two-fold increased closing rates. A T119A mutant shows favorable properties relative to wild-type and previously reported ChRmine variants for optogenetics. These results provide insight into structural features that generate an ultra-potent microbial opsin and provide a platform for rational engineering of channelrhodopsins with improved properties that could expand the scale, depth, and precision of optogenetic experiments.
Collapse
Affiliation(s)
- Kyle Tucker
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA
- California Institute for Quantitative Biology (QB3), University of California, Berkeley, CA, 94720, USA
| | - Savitha Sridharan
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Hillel Adesnik
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA.
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA.
| | - Stephen G Brohawn
- Department of Molecular & Cell Biology, University of California Berkeley, Berkeley, CA, 94720, USA.
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA.
- California Institute for Quantitative Biology (QB3), University of California, Berkeley, CA, 94720, USA.
| |
Collapse
|
69
|
Gao X, Kuo CW, Main A, Brown E, Rios FJ, Camargo LDL, Mary S, Wypijewski K, Gök C, Touyz RM, Fuller W. Palmitoylation regulates cellular distribution of and transmembrane Ca flux through TrpM7. Cell Calcium 2022; 106:102639. [PMID: 36027648 DOI: 10.1016/j.ceca.2022.102639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 08/03/2022] [Accepted: 08/14/2022] [Indexed: 11/19/2022]
Abstract
The bifunctional cation channel/kinase TrpM7 is ubiquitously expressed and regulates embryonic development and pathogenesis of several common diseases. The TrpM7 integral membrane ion channel domain regulates transmembrane movement of divalent cations, and its kinase domain controls gene expression via histone phosphorylation. Mechanisms regulating TrpM7 are elusive. It exists in two populations in the cell: at the cell surface where it controls divalent cation fluxes, and in intracellular vesicles where it controls zinc uptake and release. Here we report that TrpM7 is palmitoylated at a cluster of cysteines at the C terminal end of its Trp domain. Palmitoylation controls the exit of TrpM7 from the endoplasmic reticulum and the distribution of TrpM7 between cell surface and intracellular pools. Using the Retention Using Selective Hooks (RUSH) system, we demonstrate that palmitoylated TrpM7 traffics from the Golgi to the surface membrane whereas non-palmitoylated TrpM7 is sequestered in intracellular vesicles. We identify the Golgi-resident enzyme zDHHC17 and surface membrane-resident enzyme zDHHC5 as responsible for palmitoylating TrpM7 and find that TrpM7-mediated transmembrane calcium uptake is significantly reduced when TrpM7 is not palmitoylated. The closely related channel/kinase TrpM6 is also palmitoylated on the C terminal side of its Trp domain. Our findings demonstrate that palmitoylation controls ion channel activity of TrpM7 and that TrpM7 trafficking is dependant on its palmitoylation. We define a new mechanism for post translational modification and regulation of TrpM7 and other Trps.
Collapse
Affiliation(s)
- Xing Gao
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Chien-Wen Kuo
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Alice Main
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Elaine Brown
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Francisco J Rios
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Livia De Lucca Camargo
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Sheon Mary
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Krzysztof Wypijewski
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Caglar Gök
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Rhian M Touyz
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom; Research Institute of the McGill University Health Centre, McGill University, Montreal, Canada
| | - William Fuller
- Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
| |
Collapse
|
70
|
Wang Y, Zhao M, Xu B, Bahriz SMF, Zhu C, Jovanovic A, Ni H, Jacobi A, Kaludercic N, Di Lisa F, Hell JW, Shih JC, Paolocci N, Xiang YK. Monoamine oxidase A and organic cation transporter 3 coordinate intracellular β 1AR signaling to calibrate cardiac contractile function. Basic Res Cardiol 2022; 117:37. [PMID: 35842861 PMCID: PMC9288959 DOI: 10.1007/s00395-022-00944-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 06/28/2022] [Accepted: 07/01/2022] [Indexed: 02/03/2023]
Abstract
We have recently identified a pool of intracellular β1 adrenergic receptors (β1ARs) at the sarcoplasmic reticulum (SR) crucial for cardiac function. Here, we aim to characterize the integrative control of intracellular catecholamine for subcellular β1AR signaling and cardiac function. Using anchored Förster resonance energy transfer (FRET) biosensors and transgenic mice, we determined the regulation of compartmentalized β1AR-PKA signaling at the SR and plasma membrane (PM) microdomains by organic cation transporter 3 (OCT3) and monoamine oxidase A (MAO-A), two critical modulators of catecholamine uptake and homeostasis. Additionally, we examined local PKA substrate phosphorylation and excitation-contraction coupling in cardiomyocyte. Cardiac-specific deletion of MAO-A (MAO-A-CKO) elevates catecholamines and cAMP levels in the myocardium, baseline cardiac function, and adrenergic responses. Both MAO-A deletion and inhibitor (MAOi) selectively enhance the local β1AR-PKA activity at the SR but not PM, and augment phosphorylation of phospholamban, Ca2+ cycling, and myocyte contractile response. Overexpression of MAO-A suppresses the SR-β1AR-PKA activity and PKA phosphorylation. However, deletion or inhibition of OCT3 by corticosterone prevents the effects induced by MAOi and MAO-A deletion in cardiomyocytes. Deletion or inhibition of OCT3 also negates the effects of MAOi and MAO-A deficiency in cardiac function and adrenergic responses in vivo. Our data show that MAO-A and OCT3 act in concert to fine-tune the intracellular SR-β1AR-PKA signaling and cardiac fight-or-flight response. We reveal a drug contraindication between anti-inflammatory corticosterone and anti-depressant MAOi in modulating adrenergic regulation in the heart, providing novel perspectives of these drugs with cardiac implications.
Collapse
Affiliation(s)
- Ying Wang
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Meimi Zhao
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
- Department of Pharmaceutical Toxicology, China Medical University, Shenyang, 110122, China
| | - Bing Xu
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
- VA Northern California Health Care System, Mather, CA, USA
| | - Sherif M F Bahriz
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Chaoqun Zhu
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Aleksandra Jovanovic
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Haibo Ni
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Ariel Jacobi
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Nina Kaludercic
- Neuroscience Institute, National Research Council of Italy, Padua, Italy
- Institute for Pediatric Research Città Della Speranza, Padua, Italy
| | - Fabio Di Lisa
- Neuroscience Institute, National Research Council of Italy, Padua, Italy
- Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - Johannes W Hell
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA
| | - Jean C Shih
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA, USA
| | - Nazareno Paolocci
- Division of Cardiology, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - Yang K Xiang
- Department of Pharmacology, University of California at Davis, Davis, CA, 95616, USA.
- VA Northern California Health Care System, Mather, CA, USA.
| |
Collapse
|
71
|
Zhao Y, Shen J, Wang Q, Ruiz Munevar MJ, Vidossich P, De Vivo M, Zhou M, Cao E. Structure of the human cation-chloride cotransport KCC1 in an outward-open state. Proc Natl Acad Sci U S A 2022; 119:e2109083119. [PMID: 35759661 PMCID: PMC9271165 DOI: 10.1073/pnas.2109083119] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 04/25/2022] [Indexed: 12/30/2022] Open
Abstract
Cation-chloride cotransporters (CCCs) catalyze electroneutral symport of Cl- with Na+ and/or K+ across membranes. CCCs are fundamental in cell volume homeostasis, transepithelia ion movement, maintenance of intracellular Cl- concentration, and neuronal excitability. Here, we present a cryoelectron microscopy structure of human K+-Cl- cotransporter (KCC)1 bound with the VU0463271 inhibitor in an outward-open state. In contrast to many other amino acid-polyamine-organocation transporter cousins, our first outward-open CCC structure reveals that opening the KCC1 extracellular ion permeation path does not involve hinge-bending motions of the transmembrane (TM) 1 and TM6 half-helices. Instead, rocking of TM3 and TM8, together with displacements of TM4, TM9, and a conserved intracellular loop 1 helix, underlie alternate opening and closing of extracellular and cytoplasmic vestibules. We show that KCC1 intriguingly exists in one of two distinct dimeric states via different intersubunit interfaces. Our studies provide a blueprint for understanding the mechanisms of CCCs and their inhibition by small molecule compounds.
Collapse
Affiliation(s)
- Yongxiang Zhao
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112
| | - Jiemin Shen
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030
| | - Qinzhe Wang
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112
| | | | | | - Marco De Vivo
- Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Ming Zhou
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030
| | - Erhu Cao
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112
| |
Collapse
|
72
|
Spontarelli K, Infield DT, Nielsen HN, Holm R, Young VC, Galpin JD, Ahern CA, Vilsen B, Artigas P. Role of a conserved ion-binding site tyrosine in ion selectivity of the Na+/K+ pump. J Gen Physiol 2022; 154:e202113039. [PMID: 35657726 PMCID: PMC9171065 DOI: 10.1085/jgp.202113039] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 04/19/2022] [Accepted: 05/16/2022] [Indexed: 01/07/2023] Open
Abstract
The essential transmembrane Na+ and K+ gradients in animal cells are established by the Na+/K+ pump, a P-type ATPase that exports three Na+ and imports two K+ per ATP hydrolyzed. The mechanism by which the Na+/K+ pump distinguishes between Na+ and K+ at the two membrane sides is poorly understood. Crystal structures identify two sites (sites I and II) that bind Na+ or K+ and a third (site III) specific for Na+. The side chain of a conserved tyrosine at site III of the catalytic α-subunit (Xenopus-α1 Y780) has been proposed to contribute to Na+ binding by cation-π interaction. We substituted Y780 with natural and unnatural amino acids, expressed the mutants in Xenopus oocytes and COS-1 cells, and used electrophysiology and biochemistry to evaluate their function. Substitutions disrupting H-bonds impaired Na+ interaction, while Y780Q strengthened it, likely by H-bond formation. Utilizing the non-sense suppression method previously used to incorporate unnatural derivatives in ion channels, we were able to analyze Na+/K+ pumps with fluorinated tyrosine or phenylalanine derivatives inserted at position 780 to diminish cation-π interaction strength. In line with the results of the analysis of mutants with natural amino acid substitutions, the results with the fluorinated derivatives indicate that Na+-π interaction with the phenol ring at position 780 contributes minimally, if at all, to the binding of Na+. All Y780 substitutions decreased K+ apparent affinity, highlighting that a state-dependent H-bond network is essential for the selectivity switch at sites I and II when the pump changes conformational state.
Collapse
Affiliation(s)
- Kerri Spontarelli
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX
| | - Daniel T. Infield
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA
| | - Hang N. Nielsen
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Rikke Holm
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Victoria C. Young
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX
| | - Jason D. Galpin
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA
| | - Christopher A. Ahern
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, IA
| | - Bente Vilsen
- Department of Biomedicine, Aarhus University, Aarhus C, Denmark
| | - Pablo Artigas
- Department of Cell Physiology and Molecular Biophysics, Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX
| |
Collapse
|
73
|
Hau RK, Klein RR, Wright SH, Cherrington NJ. Localization of Xenobiotic Transporters Expressed at the Human Blood-Testis Barrier. Drug Metab Dispos 2022; 50:770-780. [PMID: 35307651 PMCID: PMC9190233 DOI: 10.1124/dmd.121.000748] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 03/07/2022] [Indexed: 10/21/2023] Open
Abstract
The blood-testis barrier (BTB) is formed by basal tight junctions between adjacent Sertoli cells (SCs) of the seminiferous tubules and acts as a physical barrier to protect developing germ cells in the adluminal compartment from reproductive toxicants. Xenobiotics, including antivirals, male contraceptives, and cancer chemotherapeutics, are known to cross the BTB, although the mechanisms that permit barrier circumvention are generally unknown. This study used immunohistological staining of human testicular tissue to determine the site of expression for xenobiotic transporters that facilitate transport across the BTB. Organic anion transporter (OAT) 1, OAT2, and organic cation transporter, novel (OCTN) 1 primarily localized to the basal membrane of SCs, whereas OCTN2, multidrug resistance protein (MRP) 3, MRP6, and MRP7 localized to SC basal membranes and peritubular myoid cells (PMCs) surrounding the seminiferous tubules. Concentrative nucleoside transporter (CNT) 2 localized to Leydig cells (LCs), PMCs, and SC apicolateral membranes. Organic cation transporter (OCT) 1, OCT2, and OCT3 mostly localized to PMCs and LCs, although there was minor staining in developing germ cells for OCT3. Organic anion transporting polypeptide (OATP) 1A2, OATP1B1, OATP1B3, OATP2A1, OATP2B1, and OATP3A1-v2 localized to SC basal membranes with diffuse staining for some transporters. Notably, OATP1C1 and OATP4A1 primarily localized to LCs. Positive staining for multidrug and toxin extrusion protein (MATE) 1 was only observed throughout the adluminal compartment. Definitive staining for CNT1, OAT3, MATE2, and OATP6A1 was not observed. The location of these transporters is consistent with their involvement in the movement of xenobiotics across the BTB. Altogether, the localization of these transporters provides insight into the mechanisms of drug disposition across the BTB and will be useful in developing tools to overcome the pharmacokinetic and pharmacodynamic difficulties presented by the BTB. SIGNIFICANCE STATEMENT: Although the total mRNA and protein expression of drug transporters in the testes has been explored, the localization of many transporters at the blood-testis barrier (BTB) has not been determined. This study applied immunohistological staining in human testicular tissues to identify the cellular localization of drug transporters in the testes. The observations made in this study have implications for the development of drugs that can effectively use transporters expressed at the basal membranes of Sertoli cells to bypass the BTB.
Collapse
Affiliation(s)
- Raymond K Hau
- Department of Pharmacology & Toxicology, College of Pharmacy (R.K.H., N.J.C.), and Departments of Pathology (R.R.K.) and Physiology (S.H.W.), College of Medicine, University of Arizona, Tucson, Arizona
| | - Robert R Klein
- Department of Pharmacology & Toxicology, College of Pharmacy (R.K.H., N.J.C.), and Departments of Pathology (R.R.K.) and Physiology (S.H.W.), College of Medicine, University of Arizona, Tucson, Arizona
| | - Stephen H Wright
- Department of Pharmacology & Toxicology, College of Pharmacy (R.K.H., N.J.C.), and Departments of Pathology (R.R.K.) and Physiology (S.H.W.), College of Medicine, University of Arizona, Tucson, Arizona
| | - Nathan J Cherrington
- Department of Pharmacology & Toxicology, College of Pharmacy (R.K.H., N.J.C.), and Departments of Pathology (R.R.K.) and Physiology (S.H.W.), College of Medicine, University of Arizona, Tucson, Arizona
| |
Collapse
|
74
|
Kawoosa F, Shah ZA, Masoodi SR, Amin A, Rasool R, Fazili KM, Dar AH, Lone A, Ul Bashir S. Role of human organic cation transporter-1 (OCT-1/SLC22A1) in modulating the response to metformin in patients with type 2 diabetes. BMC Endocr Disord 2022; 22:140. [PMID: 35619086 PMCID: PMC9137212 DOI: 10.1186/s12902-022-01033-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/26/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Organic cation transporter 1 primarily governs the action of metformin in the liver. There are considerable inter-individual variations in metformin response. In light of this, it is crucial to obtain a greater understanding of the influence of OCT1 expression or polymorphism in the context of variable responses elicited by metformin treatment. RESULTS We observed that the variable response to metformin in the responders and non-responders is independent of isoform variation and mRNA expression of OCT-1. We also observed an insignificant difference in the serum metformin levels of the patient groups. Further, molecular docking provided us with an insight into the hotspot regions of OCT-1 for metformin binding. Genotyping of these regions revealed SNPs 156T>C and 1222A>G in both the groups, while as 181C>T and 1201G>A were found only in non-responders. The 181T>C and 1222A>G changes were further found to alter OCT-1 structure in silico and affect metformin transport in vitro which was illustrated by their effect on the activation of AMPK, the marker for metformin activity. CONCLUSION Taken together, our results corroborate the role of OCT-1 in the transport of metformin and also point at OCT1 genetic variations possibly affecting the transport of metformin into the cells and hence its subsequent action in responders and non-responders.
Collapse
Affiliation(s)
- Fizalah Kawoosa
- Department of Immunology and Molecular Medicine, Sher-I-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, 190011, India
| | - Zafar A Shah
- Department of Immunology and Molecular Medicine, Sher-I-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, 190011, India.
| | - Shariq R Masoodi
- Department of Endocrinology, Sher-I-Kashmir Institute of Medical Sciences, Soura, Srinagar, Jammu and Kashmir, 190011, India
| | - Asif Amin
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, 190006, India
| | - Roohi Rasool
- Department of Immunology and Molecular Medicine, Sher-I-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, 190011, India
| | - Khalid M Fazili
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, 190006, India
| | - Abid Hamid Dar
- Department of Biotechnology, Central University of Kashmir, Ganderbal, Jammu and Kashmir, 191201, India
| | - Asif Lone
- Department of Biochemistry, Deshbandhu College, University of Delhi, Delhi, 110019, India
| | - Samir Ul Bashir
- Department of Chemistry, University of Northern British Columbia, Prince George, Canada
| |
Collapse
|
75
|
Han S, Feng Y, Guo M, Hao Y, Sun J, Zhao Y, Dong Q, Zhao Y, Cui M. Role of OCT3 and DRP1 in the Transport of Paraquat in Astrocytes: A Mouse Study. Environ Health Perspect 2022; 130:57004. [PMID: 35511227 PMCID: PMC9070608 DOI: 10.1289/ehp9505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 03/24/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Paraquat (PQ) is a pesticide, exposure to which has been associated with an increased risk of Parkinson's disease; however, PQ transport mechanisms in the brain are still unclear. Our previous studies indicated that the organic cation transporter 3 (OCT3) expressed on astrocytes could uptake PQ and protect the dopaminergic (DA) neurons from a higher level of extracellular PQ. At present, it is unknown how OCT3 levels are altered during chronic PQ exposure or aging, nor is it clear how the compensatory mechanisms are triggered by OCT3 deficiency. Dynamic related protein 1 (DRP1) was previously reported to ameliorate the loss of neurons during Parkinson's disease. Nowadays, mounting studies have revealed the functions of astrocyte DRP1, prompting us to hypothesize that DRP1 could regulate the PQ transport capacity of astrocytes. OBJECTIVES The present study aimed to further explore PQ transport mechanisms in the nigrostriatal system and identify pathways involved in extracellular PQ clearance. METHODS Models of PQ-induced neurodegeneration were established by intraperitoneal (i.p.) injection of PQ in wild-type (WT) and organic cation transporter-3-deficient (Oct3-/-) mice. DRP1 knockdown was achieved by viral tools in vivo and small interfering RNA (siRNA) in vitro. Extracellular PQ was detected by in vivo microdialysis. In vitro transport assays were used to directly observe the functions of different transporters. PQ-induced neurotoxicity was evaluated by tyrosine hydroxylase immunohistochemistry, in vivo microdialysis for striatal DA and behavior tests. Western blotting analysis or immunofluorescence was used to evaluate the expression levels and locations of proteins in vitro or in vivo. RESULTS Older mice and those chronically exposed to PQ had a lower expression of brain OCT3 and, following exposure to a 10-mg/kg i.p. PQ2+ loading dose, a higher concentration of extracellular PQ. DRP1 levels were higher in astrocytes and neurons of WT and Oct3-/- mice after chronic exposure to PQ; this was supported by finding higher levels of DRP1 after PQ treatment of dopamine transporter-expressing neurons with and without OCT3 inhibition and in primary astrocytes of WT and Oct3-/- mice. Selective astrocyte DRP1 knockdown ameliorated the PQ2+-induced neurotoxicity in Oct3-/- mice but not in WT mice. GL261 astrocytes with siRNA-mediated DRP1 knockdown had a higher expression of alanine-serine-cysteine transporter 2 (ASCT2), and transport studies suggest that extracellular PQ was transported into astrocytes by ASCT2 when OCT3 was absent. DISCUSSION The present study mainly focused on the transport mechanisms of PQ between the dopaminergic neurons and astrocytes. Lower OCT3 levels were found in the older or chronically PQ-treated mice. Astrocytes with DRP1 inhibition (by viral tools or mitochondrial division inhibitor-1) had higher levels of ASCT2, which we hypothesize served as an alternative transporter to remove extracellular PQ when OCT3 was deficient. In summary, our data suggest that OCT3, ASCT2 located on astrocytes and the dopamine transporter located on DA terminals may function in a concerted manner to mediate striatal DA terminal damage in PQ-induced neurotoxicity. https://doi.org/10.1289/EHP9505.
Collapse
Affiliation(s)
- Sida Han
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yiwei Feng
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Min Guo
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yining Hao
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Jian Sun
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Yichen Zhao
- Department of Neurology, Tenth People’s Hospital, Tongji University, Shanghai, China
| | - Qiang Dong
- Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai, China
- Ministry of Education (MOE) Frontiers Center for Brain Science, Fudan University, Shanghai, China
- National Center for Neurological Disorders, Huashan Hospital, Fudan University, Shanghai, China
| | - Yanxin Zhao
- Department of Neurology, Tenth People’s Hospital, Tongji University, Shanghai, China
| | - Mei Cui
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
- National Center for Neurological Disorders, Huashan Hospital, Fudan University, Shanghai, China
| |
Collapse
|
76
|
Kim NH, Jacob P, Dangl JL. Con-Ca 2+ -tenating plant immune responses via calcium-permeable cation channels. New Phytol 2022; 234:813-818. [PMID: 35181918 PMCID: PMC9994437 DOI: 10.1111/nph.18044] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/06/2022] [Indexed: 05/24/2023]
Abstract
Calcium serves as a second messenger in a variety of developmental and physiological processes and has long been identified as important for plant immune responses. We discuss recent discoveries regarding plant immune-related calcium-permeable channels and how the two intertwined branches of the plant immune system are intricately linked to one another through calcium signalling. Cell surface immune receptors carefully tap the immense calcium gradient that exists between apoplast and cytoplasm in a short burst via tightly regulated plasma membrane (PM)-resident cation channels. Intracellular immune receptors form atypical calcium-permeable cation channels at the PM and mediate a prolonged calcium influx, overcoming the deleterious influence of pathogen effectors and enhancing plant immune responses.
Collapse
Affiliation(s)
- Nak Hyun Kim
- Department of Biology and Howard Hughes Medical InstituteUniversity of North Carolina at Chapel HillChapel HillNC27599USA
| | - Pierre Jacob
- Department of Biology and Howard Hughes Medical InstituteUniversity of North Carolina at Chapel HillChapel HillNC27599USA
| | - Jeffery L. Dangl
- Department of Biology and Howard Hughes Medical InstituteUniversity of North Carolina at Chapel HillChapel HillNC27599USA
| |
Collapse
|
77
|
Hu T, Zha W, Sun A, Wang J. Live Tissue Imaging Reveals Distinct Transcellular Pathways for Organic Cations and Anions at the Blood-Cerebrospinal Fluid Barrier. Mol Pharmacol 2022; 101:334-342. [PMID: 35193935 PMCID: PMC9092482 DOI: 10.1124/molpharm.121.000439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Accepted: 01/31/2022] [Indexed: 11/22/2022] Open
Abstract
Formed by the choroid plexus epithelial (CPE) cells, the blood-cerebrospinal fluid barrier (BCSFB) plays an active role in removing drugs, toxins, and metabolic wastes from the brain. Several organic cation and anion transporters are expressed in the CPE cells, but how they functionally mediate transepithelial transport of organic cations and anions remain unclear. In this study, we visualized the transcellular transport of fluorescent organic cation and organic anion probes using live tissue imaging in freshly isolated mouse choroid plexuses (CPs). The cationic probe, 4-[4-(dimethylamino)phenyl]-1-methylpyridinium iodide (IDT307) was transported into CPE cells at the apical membrane and highly accumulated in mitochondria. Consistent with the lack of expression of organic cation efflux transporters, there was little efflux of IDT307 into the blood capillary space. Furthermore, IDT307 uptake and intracellular accumulation was attenuated by approximately 70% in CP tissues from mice with targeted deletion of the plasma membrane monoamine transporter (Pmat). In contrast, the anionic probe fluorescein-methotrexate (FL-MTX) was rapidly transported across the CPE cells into the capillary space with little intracellular accumulation. Rifampicin, an inhibitor of organic anion transporting polypeptides (OATPs), completely blocked FL-MTX uptake into the CPE cells whereas MK-571, a pan-inhibitor of multidrug resistance associated proteins (MRPs), abolished basolateral efflux of FL-MTX. In summary, our results suggest distinct transcellular transport pathways for organic cations and anions at the BCSFB and reveal a pivotal role of PMAT, OATP and MRP transporters in organic cation and anion transport at the blood-cerebrospinal fluid interface. SIGNIFICANCE STATEMENT: Live tissue imaging revealed that while organic cations are transported from the cerebrospinal fluid (CSF) into the choroid plexus epithelial cells by plasma membrane monoamine transporter without efflux into the blood, amphipathic anions in the CSF are efficiently transported across the BCSFB through the collaborated function of apical organic anion transporting polypeptides and basolateral multidrug resistance associated proteins. These findings contribute to a mechanistic understanding of the molecular and cellular pathways for choroid plexus clearance of solutes from the brain.
Collapse
Affiliation(s)
- Tao Hu
- Department of Pharmaceutics, University of Washington, Seattle, Washington
| | - Weibin Zha
- Department of Pharmaceutics, University of Washington, Seattle, Washington
| | - Austin Sun
- Department of Pharmaceutics, University of Washington, Seattle, Washington
| | - Joanne Wang
- Department of Pharmaceutics, University of Washington, Seattle, Washington
| |
Collapse
|
78
|
Hao J, Peng A, Li Y, Zuo H, Li P, Wang J, Yu K, Liu C, Zhao S, Wan X, Pittman JK, Zhao J. Tea plant roots respond to aluminum-induced mineral nutrient imbalances by transcriptional regulation of multiple cation and anion transporters. BMC Plant Biol 2022; 22:203. [PMID: 35439932 PMCID: PMC9017051 DOI: 10.1186/s12870-022-03570-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/28/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Tea is one of the most popular non-alcoholic beverages in the world for its flavors and numerous health benefits. The tea tree (Camellia sinensis L.) is a well-known aluminum (Al) hyperaccumulator. However, it is not fully understood how tea plants have adapted to tolerate high concentrations of Al, which causes an imbalance of mineral nutrition in the roots. RESULTS Here, we combined ionomic and transcriptomic profiling alongside biochemical characterization, to probe the changes of metal nutrients and Al responsive genes in tea roots grown under increasing concentrations of Al. It was found that a low level of Al (~ 0.4 mM) maintains proper nutrient balance, whereas a higher Al concentration (2.5 mM) compromised tea plants by altering micro- and macro-nutrient accumulation into roots, including a decrease in calcium (Ca), manganese (Mn), and magnesium (Mg) and an increase in iron (Fe), which corresponded with oxidative stress, cellular damage, and retarded root growth. Transcriptome analysis revealed more than 1000 transporter genes that were significantly changed in expression upon Al exposure compared to control (no Al) treatments. These included transporters related to Ca and Fe uptake and translocation, while genes required for N, P, and S nutrition in roots did not significantly alter. Transporters related to organic acid secretion, together with other putative Al-tolerance genes also significantly changed in response to Al. Two of these transporters, CsALMT1 and CsALS8, were functionally tested by yeast heterologous expression and confirmed to provide Al tolerance. CONCLUSION This study shows that tea plant roots respond to high Al-induced mineral nutrient imbalances by transcriptional regulation of both cation and anion transporters, and therefore provides new insights into Al tolerance mechanism of tea plants. The altered transporter gene expression profiles partly explain the imbalanced metal ion accumulation that occurred in the Al-stressed roots, while increases to organic acid and Al tolerance gene expression partly explains the ability of tea plants to be able to grow in high Al containing soils. The improved transcriptomic understanding of Al exposure gained here has highlighted potential gene targets for breeding or genetic engineering approaches to develop safer tea products.
Collapse
Affiliation(s)
- Jing Hao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Anqi Peng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Yingying Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Hao Zuo
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Ping Li
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Jinsong Wang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Keke Yu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Chun Liu
- BGI Institute of Applied Agriculture, BGI–Shenzhen, Shenzhen, 518083 China
| | - Shancen Zhao
- BGI Institute of Applied Agriculture, BGI–Shenzhen, Shenzhen, 518083 China
| | - Xiaochun Wan
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| | - Jon K. Pittman
- Department of Earth and Environmental Sciences, Faculty of Science and Engineering, The University of Manchester, M13 9PT, Manchester, UK
| | - Jian Zhao
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 West Changjiang Road, Hefei, 230036 China
| |
Collapse
|
79
|
Han L, Wu X, Zhang X, Hou K, Zhang H, Shen C. Identification and functional analysis of cation-efflux transporter 1 from Brassica juncea L. BMC Plant Biol 2022; 22:174. [PMID: 35387616 PMCID: PMC8985314 DOI: 10.1186/s12870-022-03569-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/31/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Brassica juncea behaves as a moderate-level accumulator of various heavy metal ions and is frequently used for remediation. To investigate the roles of metal ion transporters in B. juncea, a cation-efflux family gene, BjCET1, was cloned and functionally characterized. RESULTS BjCET1 contains 382 amino acid residues, including a signature motif of the cation diffusion facilitator protein family, six classic trans-membrane-spanning structures and a cation-efflux domain. A phylogenetic analysis showed that BjCET1 has a high similarity level with metal tolerance proteins from other Brassica plants, indicating that this protein family is highly conserved in Brassica. BjCET1 expression significantly increased at very early stages during both cadmium and zinc treatments. Green fluorescence detection in transgenic tobacco leaves revealed that BjCET1 is a plasma membrane-localized protein. The heterologous expression of BjCET1 in a yeast mutant increased the heavy-metal tolerance and decreased the cadmium or zinc accumulations in yeast cells, suggesting that BjCET1 is a metal ion transporter. The constitutive expression of BjCET1 rescued the heavy-metal tolerance capability of transgenic tobacco plants. CONCLUSIONS The data suggest that BjCET1 is a membrane-localized efflux transporter that plays essential roles in heavy metal ion homeostasis and hyper-accumulation.
Collapse
Affiliation(s)
- Lu Han
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 China
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 Zhejiang China
| | - Xiaohua Wu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 China
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 Zhejiang China
| | - Xinyu Zhang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 China
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 Zhejiang China
| | - Kailin Hou
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 China
- Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, Hangzhou Normal University, Hangzhou, 310036 China
| | - Hongshan Zhang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 China
- Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, Hangzhou Normal University, Hangzhou, 310036 China
| | - Chenjia Shen
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036 China
- Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, Hangzhou Normal University, Hangzhou, 310036 China
| |
Collapse
|
80
|
Wang J, Chen G, Liu N, Han X, Zhao F, Zhang L, Chen P. Strategies for improving the safety and RNAi efficacy of noncovalent peptide/siRNA nanocomplexes. Adv Colloid Interface Sci 2022; 302:102638. [PMID: 35299136 DOI: 10.1016/j.cis.2022.102638] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/04/2022] [Accepted: 03/04/2022] [Indexed: 12/12/2022]
Abstract
In the past decades, the striking development of cationic polypeptides and cell-penetrating peptides (CPPs) tailored for small interfering RNA (siRNA) delivery has been fuelled by the conception of nuclear acid therapy and precision medicine. Owing to their amino acid compositions, inherent secondary structures as well as diverse geometrical shapes, peptides or peptide-containing polymers exhibit good biodegradability, high flexibility, and bio-functional diversity as nonviral siRNA vectors. Also, a variety of noncovalent nanocomplexes could be built via self-assembling and electrostatic interactions between cationic peptides and siRNAs. Although the peptide/siRNA nanocomplex-based RNAi therapies, STP705 and MIR-19, are under clinical trials, a guideline addressing the current bottlenecks of peptide/siRNA nanocomplex delivery is in high demand for future research and development. In this review, we present strategies for improving the safety and RNAi efficacy of noncovalent peptide/siRNA nanocomplexes in the treatment of genetic disorders. Through thorough analysis of those RNAi formulations using different delivery strategies, we seek to shed light on the rationale of peptide design and modification in constructing robust siRNA delivery systems, including targeted and co-delivery systems. Based on this, we provide a timely and comprehensive understanding of how to engineer biocompatible and efficient peptide-based siRNA vectors.
Collapse
Affiliation(s)
- Jun Wang
- Department of Chemical Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Guang Chen
- Department of Chemical Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada; Key Laboratory of Chemical Additives for China National Light Industry, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
| | - Nan Liu
- Advanced Materials Institute, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250014, China
| | - Xiaoxia Han
- Department of Chemical Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Feng Zhao
- Department of Chemical Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - Lei Zhang
- Department of Chemical Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
| | - P Chen
- Department of Chemical Engineering and Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada; Advanced Materials Institute, Qilu University of Technology, Shandong Academy of Sciences, Jinan 250014, China.
| |
Collapse
|
81
|
Huang X, Shabala L, Zhang X, Zhou M, Voesenek LACJ, Hartman S, Yu M, Shabala S. Cation transporters in cell fate determination and plant adaptive responses to a low-oxygen environment. J Exp Bot 2022; 73:636-645. [PMID: 34718542 DOI: 10.1093/jxb/erab480] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
Soil flooding creates low-oxygen environments in root zones and thus severely affects plant growth and productivity. Plants adapt to low-oxygen environments by a suite of orchestrated metabolic and anatomical alterations. Of these, formation of aerenchyma and development of adventitious roots are considered very critical to enable plant performance in waterlogged soils. Both traits have been firmly associated with stress-induced increases in ethylene levels in root tissues that operate upstream of signalling pathways. Recently, we used a bioinformatic approach to demonstrate that several Ca2+ and K+ -permeable channels from KCO, AKT, and TPC families could also operate in low oxygen sensing in Arabidopsis. Here we argue that low-oxygen-induced changes to cellular ion homeostasis and operation of membrane transporters may be critical for cell fate determination and formation of the lysigenous aerenchyma in plant roots and shaping the root architecture and adventitious root development in grasses. We summarize the existing evidence for a causal link between tissue-specific changes in oxygen concentration, intracellular Ca2+ and K+ homeostasis, and reactive oxygen species levels, and their role in conferring those two major traits enabling plant adaptation to a low-oxygen environment. We conclude that, for efficient operation, plants may rely on several complementary signalling pathway mechanisms that operate in concert and 'fine-tune' each other. A better understanding of this interaction may create additional and previously unexplored opportunities to crop breeders to improve cereal crop yield losses to soil flooding.
Collapse
Affiliation(s)
- Xin Huang
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528041, China
| | - Lana Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas 7001, Australia
| | - Xuechen Zhang
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas 7001, Australia
| | - Meixue Zhou
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas 7001, Australia
| | | | - Sjon Hartman
- Plant Ecophysiology, Utrecht University, 3584 CH Utrecht, The Netherlands
- School of Biosciences, University of Birmingham, Edgbaston B15 2TT, UK
| | - Min Yu
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528041, China
| | - Sergey Shabala
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528041, China
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, Tas 7001, Australia
| |
Collapse
|
82
|
Wheeler S, Breen C, Li Y, Hewitt SH, Robertson E, Yates EA, Barsukov IL, Fernig DG, Butler SJ. Anion binding to a cationic europium(III) probe enables the first real-time assay of heparan sulfotransferase activity. Org Biomol Chem 2022; 20:596-605. [PMID: 34951618 PMCID: PMC8767414 DOI: 10.1039/d1ob02071d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 11/18/2021] [Indexed: 12/25/2022]
Abstract
Sulfotransferases constitute a ubiquitous class of enzymes which are poorly understood due to the lack of a convenient tool for screening their activity. These enzymes use the anion PAPS (adenosine-3'-phosphate-5'-phosphosulfate) as a donor for a broad range of acceptor substrates, including carbohydrates, producing sulfated compounds and PAP (adenosine-3',5'-diphosphate) as a side product. We present a europium(III)-based probe that binds reversibly to both PAPS and PAP, producing a larger luminescence enhancement with the latter anion. We exploit this greater emission enhancement with PAP to demonstrate the first direct real-time assay of a heparan sulfate sulfotransferase using a multi-well plate format. The selective response of our probe towards PAP over structurally similar nucleoside phosphate anions, and over other anions, is investigated and discussed. This work opens the possibility of investigating more fully the roles played by this enzyme class in health and disease, including operationally simple inhibitor screening.
Collapse
Affiliation(s)
- Simon Wheeler
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Colum Breen
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Yong Li
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Sarah H Hewitt
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Erin Robertson
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| | - Edwin A Yates
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Igor L Barsukov
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - David G Fernig
- Department of Biochemistry, Institute for Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Stephen J Butler
- Department of Chemistry, Loughborough University, Epinal Way, Loughborough, LE11 3TU, UK.
| |
Collapse
|
83
|
Spix B, Jeridi A, Ansari M, Yildirim AÖ, Schiller HB, Grimm C. Endolysosomal Cation Channels and Lung Disease. Cells 2022; 11:304. [PMID: 35053420 PMCID: PMC8773812 DOI: 10.3390/cells11020304] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/20/2021] [Accepted: 12/25/2021] [Indexed: 12/28/2022] Open
Abstract
Endolysosomal cation channels are emerging as key players of endolysosomal function such as endolysosomal trafficking, fusion/fission, lysosomal pH regulation, autophagy, lysosomal exocytosis, and endocytosis. Diseases comprise lysosomal storage disorders (LSDs) and neurodegenerative diseases, metabolic diseases, pigmentation defects, cancer, immune disorders, autophagy related diseases, infectious diseases and many more. Involvement in lung diseases has not been a focus of attention so far but recent developments in the field suggest critical functions in lung physiology and pathophysiology. Thus, loss of TRPML3 was discovered to exacerbate emphysema formation and cigarette smoke induced COPD due to dysregulated matrix metalloproteinase 12 (MMP-12) levels in the extracellular matrix of the lung, a known risk factor for emphysema/COPD. While direct lung function measurements with the exception of TRPML3 are missing for other endolysosomal cation channels or channels expressed in lysosome related organelles (LRO) in the lung, links between those channels and important roles in lung physiology have been established such as the role of P2X4 in surfactant release from alveolar epithelial Type II cells. Other channels with demonstrated functions and disease relevance in the lung such as TRPM2, TRPV2, or TRPA1 may mediate their effects due to plasma membrane expression but evidence accumulates that these channels might also be expressed in endolysosomes, suggesting additional and/or dual roles of these channels in cell and intracellular membranes. We will discuss here the current knowledge on cation channels residing in endolysosomes or LROs with respect to their emerging roles in lung disease.
Collapse
Affiliation(s)
- Barbara Spix
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, 80336 Munich, Germany;
| | - Aicha Jeridi
- Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764 Munich, Germany; (A.J.); (M.A.); (A.Ö.Y.); (H.B.S.)
| | - Meshal Ansari
- Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764 Munich, Germany; (A.J.); (M.A.); (A.Ö.Y.); (H.B.S.)
| | - Ali Önder Yildirim
- Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764 Munich, Germany; (A.J.); (M.A.); (A.Ö.Y.); (H.B.S.)
| | - Herbert B. Schiller
- Pneumology Center, Institute of Lung Biology and Disease, Helmholtz Zentrum München, 85764 Munich, Germany; (A.J.); (M.A.); (A.Ö.Y.); (H.B.S.)
| | - Christian Grimm
- Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, 80336 Munich, Germany;
| |
Collapse
|
84
|
Rozga-Wijas K, Bak-Sypien I, Turecka K, Narajczyk M, Waleron K. Cationic Phenosafranin Photosensitizers Based on Polyhedral Oligomeric Silsesquioxanes for Inactivation of Gram-Positive and Gram-Negative Bacteria. Int J Mol Sci 2021; 22:ijms222413373. [PMID: 34948170 PMCID: PMC8708100 DOI: 10.3390/ijms222413373] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/03/2021] [Accepted: 12/09/2021] [Indexed: 01/25/2023] Open
Abstract
The high photodynamic effect of the Newman strain of the S. aureus and of clinical strains of S. aureus MRSA 12673 and E. coli 12519 are observed for new cationic light-activated phenosafranin polyhedral oligomeric silsesquioxane (POSS) conjugates in vitro. Killing of bacteria was achieved at low concentrations of silsesquioxanes (0.38 µM) after light irradiation (λem. max = 522 nm, 10.6 mW/cm2) for 5 min. Water-soluble POSS-photosensitizers are synthesized by chemically coupling a phenosafranin dye (PSF) (3,7-diamino-5-phenylphenazine chloride) to an inorganic silsesquioxane cage activated by attachment of succinic anhydride rings. The chemical structure of conjugates is confirmed by 1H, 13C NMR, HRMS, IR, fluorescence spectroscopy and UV-VIS analyzes. The APDI and daunorubicin (DAU) synergy is investigated for POSSPSFDAU conjugates. Confocal microscopy experiments indicate a site of intracellular accumulation of the POSSPSF, whereas iBuPOSSPSF and POSSPSFDAU accumulate in the cell wall or cell membrane. Results from the TEM study show ruptured S. aureus cells with leaking cytosolic mass and distorted cells of E. coli. Bacterial cells are eradicated by ROS produced upon irradiation of the covalent conjugates that can kill the bacteria by destruction of cellular membranes, intracellular proteins and DNA through the oxidative damage of bacteria.
Collapse
Affiliation(s)
- Krystyna Rozga-Wijas
- Centre of Molecular and Macromolecular Studies, Polish Academy of Science, Sienkiewicza 112, 90-363 Lodz, Poland;
- Correspondence: (K.R.-W.); (K.T.); Tel.: +48-426-803-203 (K.R.-W.)
| | - Irena Bak-Sypien
- Centre of Molecular and Macromolecular Studies, Polish Academy of Science, Sienkiewicza 112, 90-363 Lodz, Poland;
| | - Katarzyna Turecka
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Medical University of Gdańsk, gen. Hallera 107, 80-416 Gdańsk, Poland;
- Correspondence: (K.R.-W.); (K.T.); Tel.: +48-426-803-203 (K.R.-W.)
| | - Magdalena Narajczyk
- Department of Electron Microscopy, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland;
| | - Krzysztof Waleron
- Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Medical University of Gdańsk, gen. Hallera 107, 80-416 Gdańsk, Poland;
| |
Collapse
|
85
|
Kuppusamy M, Ottolini M, Sonkusare SK. Role of TRP ion channels in cerebral circulation and neurovascular communication. Neurosci Lett 2021; 765:136258. [PMID: 34560190 PMCID: PMC8572163 DOI: 10.1016/j.neulet.2021.136258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 08/26/2021] [Accepted: 08/28/2021] [Indexed: 11/17/2022]
Abstract
The dynamic regulation of blood flow is essential for meeting the high metabolic demands of the brain and maintaining brain function. Cerebral blood flow is regulated primarily by 1) the intrinsic mechanisms that determine vascular contractility and 2) signals from neurons and astrocytes that alter vascular contractility. Stimuli from neurons and astrocytes can also initiate a signaling cascade in the brain capillary endothelium to increase regional blood flow. Recent studies provide evidence that TRP channels in endothelial cells, smooth muscle cells, neurons, astrocytes, and perivascular nerves control cerebrovascular contractility and cerebral blood flow. TRP channels exert their functional effects either through cell membrane depolarization or by serving as a Ca2+ influx pathway. Endothelial cells and astrocytes also maintain the integrity of the blood-brain barrier. Both endothelial cells and astrocytes express TRP channels, and an increase in endothelial TRP channel activity has been linked with a disrupted endothelial barrier function. Therefore, TRP channels can play a potentially important role in regulating blood-brain barrier integrity. Here, we review the regulation of cerebrovascular contractility by TRP channels under healthy and disease conditions and their potential roles in maintaining blood-brain barrier function.
Collapse
Affiliation(s)
- Maniselvan Kuppusamy
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, USA
| | - Matteo Ottolini
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, USA; Department of Pharmacology, University of Virginia-School of Medicine, Charlottesville, VA, USA
| | - Swapnil K Sonkusare
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, USA; Department of Molecular Physiology and Biological Physics, University of Virginia-School of Medicine, Charlottesville, VA, USA.
| |
Collapse
|
86
|
Loch JI, Imiolczyk B, Sliwiak J, Wantuch A, Bejger M, Gilski M, Jaskolski M. Crystal structures of the elusive Rhizobium etli L-asparaginase reveal a peculiar active site. Nat Commun 2021; 12:6717. [PMID: 34795296 PMCID: PMC8602277 DOI: 10.1038/s41467-021-27105-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/01/2021] [Indexed: 12/04/2022] Open
Abstract
Rhizobium etli, a nitrogen-fixing bacterial symbiont of legume plants, encodes an essential L-asparaginase (ReAV) with no sequence homology to known enzymes with this activity. High-resolution crystal structures of ReAV show indeed a structurally distinct, dimeric enzyme, with some resemblance to glutaminases and β-lactamases. However, ReAV has no glutaminase or lactamase activity, and at pH 9 its allosteric asparaginase activity is relatively high, with Km for L-Asn at 4.2 mM and kcat of 438 s-1. The active site of ReAV, deduced from structural comparisons and confirmed by mutagenesis experiments, contains a highly specific Zn2+ binding site without a catalytic role. The extensive active site includes residues with unusual chemical properties. There are two Ser-Lys tandems, all connected through a network of H-bonds to the Zn center, and three tightly bound water molecules near Ser48, which clearly indicate the catalytic nucleophile.
Collapse
Affiliation(s)
- Joanna I Loch
- Department of Crystal Chemistry and Crystal Physics, Faculty of Chemistry, Jagiellonian University, Krakow, Poland
| | - Barbara Imiolczyk
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - Joanna Sliwiak
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - Anna Wantuch
- Department of Crystal Chemistry and Crystal Physics, Faculty of Chemistry, Jagiellonian University, Krakow, Poland
| | - Magdalena Bejger
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - Miroslaw Gilski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University, Poznan, Poland
| | - Mariusz Jaskolski
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland.
- Department of Crystallography, Faculty of Chemistry, A. Mickiewicz University, Poznan, Poland.
| |
Collapse
|
87
|
Zarei A, Alihosseini F, Parida D, Nazir R, Gaan S. Fabrication of Cellulase Catalysts Immobilized on a Nanoscale Hybrid Polyaniline/Cationic Hydrogel Support for the Highly Efficient Catalytic Conversion of Cellulose. ACS Appl Mater Interfaces 2021; 13:49816-49827. [PMID: 34653337 DOI: 10.1021/acsami.1c12263] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A novel conductive nanohydrogel hybrid support was prepared by in situ polymerization of polyaniline nanorods on an electrospun cationic hydrogel of poly(ε-caprolactone) and a cationic phosphine oxide macromolecule. Subsequently, the cellulase enzyme was immobilized on the hybrid support. Field-emission scanning electron microscopy and Brunauer-Emmett-Teller analyses confirmed a mesoporous, rod-like structure with a slit-like pore geometry for the immobilized support and exhibiting a high immobilization capacity and reduced diffusion resistance of the substrate. For comparison, the catalytic activity, storage stability, and reusability of the immobilized and free enzymes were evaluated. The results showed that the immobilized enzymes have higher thermal stability without changes in the optimal pH (5.5) and temperature (55 °C) for enzyme activity. A high immobilization efficiency (96%) was observed for the immobilized cellulose catalysts after optimization of parameters such as the pH, temperature, incubation time, and protein concentration. The immobilized enzyme retained almost 90% of its original activity after 4 weeks of storage and 73% of its original activity after the ninth reuse cycle. These results strongly suggest that the prepared hybrid support has the potential to be used as a support for protein immobilization.
Collapse
Affiliation(s)
- Afsaneh Zarei
- Department of Textile Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Farzaneh Alihosseini
- Department of Textile Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
| | - Dambarudhar Parida
- Laboratory of Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, St. Gallen CH-9014, Switzerland
| | - Rashid Nazir
- Laboratory of Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, St. Gallen CH-9014, Switzerland
| | - Sabyasachi Gaan
- Laboratory of Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, St. Gallen CH-9014, Switzerland
| |
Collapse
|
88
|
Helfrich F, Scheidig AJ. Structural and catalytic characterization of Blastochloris viridis and Pseudomonas aeruginosa homospermidine synthases supports the essential role of cation-π interaction. Acta Crystallogr D Struct Biol 2021; 77:1317-1335. [PMID: 34605434 PMCID: PMC8489232 DOI: 10.1107/s2059798321008937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Accepted: 08/27/2021] [Indexed: 11/16/2022] Open
Abstract
Polyamines influence medically relevant processes in the opportunistic pathogen Pseudomonas aeruginosa, including virulence, biofilm formation and susceptibility to antibiotics. Although homospermidine synthase (HSS) is part of the polyamine metabolism in various strains of P. aeruginosa, neither its role nor its structure has been examined so far. The reaction mechanism of the nicotinamide adenine dinucleotide (NAD+)-dependent bacterial HSS has previously been characterized based on crystal structures of Blastochloris viridis HSS (BvHSS). This study presents the crystal structure of P. aeruginosa HSS (PaHSS) in complex with its substrate putrescine. A high structural similarity between PaHSS and BvHSS with conservation of the catalytically relevant residues is demonstrated, qualifying BvHSS as a model for mechanistic studies of PaHSS. Following this strategy, crystal structures of single-residue variants of BvHSS are presented together with activity assays of PaHSS, BvHSS and BvHSS variants. For efficient homospermidine production, acidic residues are required at the entrance to the binding pocket (`ionic slide') and near the active site (`inner amino site') to attract and bind the substrate putrescine via salt bridges. The tryptophan residue at the active site stabilizes cationic reaction components by cation-π interaction, as inferred from the interaction geometry between putrescine and the indole ring plane. Exchange of this tryptophan for other amino acids suggests a distinct catalytic requirement for an aromatic interaction partner with a highly negative electrostatic potential. These findings substantiate the structural and mechanistic knowledge on bacterial HSS, a potential target for antibiotic design.
Collapse
Affiliation(s)
- F. Helfrich
- Zoological Institute, University of Kiel, Am Botanischen Garten 1–9, 24118 Kiel, Germany
| | - Axel J. Scheidig
- Zoological Institute, University of Kiel, Am Botanischen Garten 1–9, 24118 Kiel, Germany
| |
Collapse
|
89
|
Koepp TN, Tokaj A, Nedvetsky PI, Conchon Costa AC, Snieder B, Schröter R, Ciarimboli G. Properties of Transport Mediated by the Human Organic Cation Transporter 2 Studied in a Polarized Three-Dimensional Epithelial Cell Culture Model. Int J Mol Sci 2021; 22:ijms22179658. [PMID: 34502566 PMCID: PMC8432172 DOI: 10.3390/ijms22179658] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/01/2021] [Accepted: 09/01/2021] [Indexed: 02/06/2023] Open
Abstract
The renal secretory clearance for organic cations (neurotransmitters, metabolism products and drugs) is mediated by transporters specifically expressed in the basolateral and apical plasma membrane domains of proximal tubule cells. Here, human organic cation transporter 2 (hOCT2) is the main transporter for organic cations in the basolateral membrane domain. In this study, we stably expressed hOCT2 in Madin-Darby Canine Kidney (MDCK) cells and cultivated these cells in the presence of an extracellular matrix to obtain three-dimensional (3D) structures (cysts). The transport properties of hOCT2 expressed in MDCK cysts were compared with those measured using human embryonic kidney cells (HEK293) stably transfected with hOCT2 (hOCT2-HEK cells). In the MDCK cysts, hOCT2 was expressed in the basolateral membrane domain and showed a significant uptake of the fluorescent organic cation 4-(4-(dimethylamino)styryl)-N-methylpyridinium (ASP+) with an affinity (Km) of 3.6 ± 1.2 µM, similar to what was measured in the hOCT2-HEK cells (Km = 3.1 ± 0.2 µM). ASP+ uptake was inhibited by tetraethylammonium (TEA+), tetrapentylammonium (TPA+), metformin and baricitinib both in the hOCT2-HEK cells and the hOCT2- MDCK cysts, even though the apparent affinities of TEA+ and baricitinib were dependent on the expression system. Then, hOCT2 was subjected to the same rapid regulation by inhibition of p56lck tyrosine kinase or calmodulin in the hOCT2-HEK cells and hOCT2- MDCK cysts. However, inhibition of casein kinase II regulated only activity of hOCT2 expressed in MDCK cysts and not in HEK cells. Taken together, these results suggest that the 3D cell culture model is a suitable tool for the functional analysis of hOCT2 transport properties, depending on cell polarization.
Collapse
|
90
|
Sawatdee S, Prommuak C, Jarunglumlert T, Pavasant P, Flood AE. Combined effects of cations in fertilizer solution on antioxidant content in red lettuce (Lactuca sativa L.). J Sci Food Agric 2021; 101:4632-4642. [PMID: 33474734 DOI: 10.1002/jsfa.11106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 01/15/2021] [Accepted: 01/21/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND Red lettuce is consumed worldwide because it is a great source of natural antioxidants. To design a fertilizer formula to boost its nutritional value, this research simultaneously studied the effects of significant cations among the macronutrients for plant growth (K, Mg and Ca) and the effects of the electrical conductivity (EC) of the nutrient solution on phenolic compound production and mass productivity of hydroponically grown red lettuce. RESULTS Red lettuce grown under the control treatment provided the highest mass productivity (under low-stress conditions). The highest antioxidant content, measured as milligrams of phenolic compounds per gram dry weight (at a high-stress condition) via both Folin-Ciocalteu and HPLC analyses, was observed in growth media containing 100 ppmK : 20 ppm Mg : 70 ppm Ca (with EC equal to 1241 μS cm-1 ). It was found that EC within the range of this examination had no significant effect on the mass productivity or on phenolic compound productivity. The phenolic compound productivity, defined as the amount of phenolic compounds produced per unit of planting area per unit of time, was optimized with the optimum formula for maximum phenolic compound productivity of 90 ppm K : 29 ppm Mg : 77 ppm Ca, or a corresponding EC of 1307 μS cm-1 . CONCLUSIONS The study demonstrates that health-promoting nutrient production in red lettuce could be stimulated in a practical manner by adjusting the cation concentrations in fertilizer solution. © 2021 Society of Chemical Industry.
Collapse
Affiliation(s)
- Sopanat Sawatdee
- School of Energy Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Rayong, Thailand
| | - Chattip Prommuak
- Energy Research Institute, Chulalongkorn University, Bangkok, Thailand
| | - Teeraya Jarunglumlert
- King Mongkut's University of Technology North Bangkok (Rayong Campus), Rayong, Thailand
| | | | - Adrian E Flood
- School of Energy Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Rayong, Thailand
| |
Collapse
|
91
|
Dubinin MV, Semenova AA, Ilzorkina AI, Penkov NV, Nedopekina DA, Sharapov VA, Khoroshavina EI, Davletshin EV, Belosludtseva NV, Spivak AY, Belosludtsev KN. Mitochondria-targeted prooxidant effects of betulinic acid conjugated with delocalized lipophilic cation F16. Free Radic Biol Med 2021; 168:55-69. [PMID: 33812008 DOI: 10.1016/j.freeradbiomed.2021.03.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/15/2021] [Accepted: 03/26/2021] [Indexed: 02/06/2023]
Abstract
The paper examines the molecular mechanisms of the cytotoxicity of conjugates of betulinic acid with the penetrating cation F16. The in vitro experiments on rat thymocytes revealed that all the obtained F16-betulinic acid derivatives showed more than 10-fold higher cytotoxicity as compared to betulinic acid and F16. In this case, 0.5-1 μM of all conjugates showed mitochondria-targeted action, inducing superoxide overproduction and reducing the mitochondrial potential of cells. Experiments on isolated rat liver mitochondria revealed the ability of conjugates to dose-dependently reduce the membrane potential of organelles, as well as the intensity of respiration and oxidative phosphorylation, which is also accompanied by an increase in the production of hydrogen peroxide by mitochondria. It was shown that these actions of derivatives may be due to several effects: the reversion of ATP synthase, changes in the activity of complexes of the respiratory chain and permeabilization of the inner mitochondrial membrane. All compounds also demonstrated the ability to induce aggregation of isolated rat liver mitochondria. Using the model of lecithin liposomes, we found that the F6 conjugate (2 μM) induces the permeability of vesicle membranes for the fluorescent probe sulforhodamine B. High concentrations (25 μM) of the F6 derivative have been found to induce dynamic processes in the liposome membrane leading to aggregation and/or fusion of vesicle membranes. The paper discusses the relationship between the mitochondria-targeted effects of F16-betulinic acid conjugates and their cytotoxicity.
Collapse
Affiliation(s)
- Mikhail V Dubinin
- Mari State University, Pl. Lenina 1, Yoshkar-Ola, Mari El, 424001, Russia.
| | - Alena A Semenova
- Mari State University, Pl. Lenina 1, Yoshkar-Ola, Mari El, 424001, Russia
| | - Anna I Ilzorkina
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya 3, Pushchino, Moscow Region, 142290, Russia
| | - Nikita V Penkov
- Institute of Cell Biophysics, Russian Academy of Sciences, PSCBR RAS, Institutskaya 3, Pushchino, Moscow Region, 142290, Russia
| | - Darya A Nedopekina
- Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Prospekt Oktyabrya 141, Ufa, Republic of Bashkortostan, 450075, Russia
| | | | | | - Eldar V Davletshin
- Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Prospekt Oktyabrya 141, Ufa, Republic of Bashkortostan, 450075, Russia
| | - Natalia V Belosludtseva
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya 3, Pushchino, Moscow Region, 142290, Russia
| | - Anna Yu Spivak
- Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Prospekt Oktyabrya 141, Ufa, Republic of Bashkortostan, 450075, Russia
| | - Konstantin N Belosludtsev
- Mari State University, Pl. Lenina 1, Yoshkar-Ola, Mari El, 424001, Russia; Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya 3, Pushchino, Moscow Region, 142290, Russia; Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilova 38, Moscow, 119991, Russia
| |
Collapse
|
92
|
Ni H, Liu J, Dai O, Feng R, Liu F, Cao XY, Peng C, Xiong L. Chemical composition and uterine smooth muscle relaxant activity of essential oils from 10 kinds of blood-activating and stasis-resolving Chinese medicinal herbs. J Ethnopharmacol 2021; 269:113713. [PMID: 33352237 DOI: 10.1016/j.jep.2020.113713] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 12/12/2020] [Accepted: 12/18/2020] [Indexed: 06/12/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Dysmenorrhea is one of the most common gynecological problems among menstruating females. Blood-activating and stasis-resolving herbs (BASRHs) have been employed to be the first choice for treating dysmenorrhea in China. Especially, the essential oils of some BASRHs have been confirmed to play important roles in the treatment of dysmenorrhea, but the constituents and uterine smooth muscle relaxant activity of some commonly used BASRH essential oils have not been fully assessed, and whether there are differences in the constituents and anti-dysmenorrhea effect among BASRH essential oils has not been evaluated. AIM OF THE STUDY This study aims to systematically investigate the chemical constituents of 10 BASRH essential oils and assess their uterine smooth muscle relaxant activity and the preliminary mechanism of the most effective essential oil. MATERIALS AND METHODS The chemical constituents of 10 BASRH essential oils were analyzed by Gas Chromatography-Mass Spectrometer. A rat model of dysmenorrhea in vitro was established to investigate the uterine smooth muscle relaxant activity of 10 kinds of essential oils. Rat isolated uterus strips were given different dose of 10 kinds of essential oils (0.04, 0.08, 0.16 mg/mL). The contractile responses were recorded with Power Lab recording system, and contractile tension, contractile frequency, and contractile activity were evaluated. The preliminary mechanism of the essential oil of the rhizomes of Curcuma phaeocaulis Valeton (CPEO) was assessed using a rat model of dysmenorrhea in vivo and in vitro, and rats were given the CPEO (15, 30, and 60 mg/kg) by gavage. The level of Ca2+ in uterine tissue of rats was determined by methyl thyme phenol blue colorimetric and Bradford methods. The effects of CPEO on extracellular Ca2+ influx and intracellular Ca2+ release were evaluated using the isolated uterus. RESULTS The results of Gas Chromatography-Mass Spectrometer analysis showed that more than 81 components (content: 1% max appearance) were identified. The main components of the 10 BASRH essential oils were found to be monoterpenoids, sesquiterpenoids, diterpenoids, aromatics, aliphatics, and phthalides. The study of in vitro smooth muscle relaxant activity demonstrated that all the essential oils except the essential oil of the roots of Cyathula officinalis K.C.Kuan markedly decrease the contractile activity, tension, and frequency (P < 0.05 or P < 0.01). Among these oils, CPEO has the most pronounced effect. Further in vivo studies indicated that CPEO can significantly decrease the level of Ca2+ in uterine tissue when compared with the model group (P < 0.05 or P < 0.01). In vitro studies indicated that CPEO can inhibit the extracellular Ca2+ influx and intracellular Ca2+ release in favor of uterine relaxation. CONCLUSIONS BASRH essential oils play an important role in inhibiting uterine smooth muscle contractions, and sesquiterpenoids and phthalides in BASRH essential oils are important active compounds for relaxing uterine smooth muscle. CPEO is a favorable candidate for developing anti-dysmenorrhea drugs.
Collapse
Affiliation(s)
- Hong Ni
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; Institute of Innovative Medicine Ingredients of Southwest Specialty Medicinal Materials, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Juan Liu
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; Institute of Innovative Medicine Ingredients of Southwest Specialty Medicinal Materials, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Ou Dai
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; Institute of Innovative Medicine Ingredients of Southwest Specialty Medicinal Materials, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Rui Feng
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; Institute of Innovative Medicine Ingredients of Southwest Specialty Medicinal Materials, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Fei Liu
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; Institute of Innovative Medicine Ingredients of Southwest Specialty Medicinal Materials, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Xiao-Yu Cao
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Cheng Peng
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| | - Liang Xiong
- School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; Institute of Innovative Medicine Ingredients of Southwest Specialty Medicinal Materials, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China; State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine, Chengdu, 611137, China.
| |
Collapse
|
93
|
Guo Y, Lee H, Fang Z, Velalopoulou A, Kim J, Thomas MB, Liu J, Abramowitz RG, Kim Y, Coskun AF, Krummel DP, Sengupta S, MacDonald TJ, Arvanitis C. Single-cell analysis reveals effective siRNA delivery in brain tumors with microbubble-enhanced ultrasound and cationic nanoparticles. Sci Adv 2021; 7:7/18/eabf7390. [PMID: 33931452 PMCID: PMC8087400 DOI: 10.1126/sciadv.abf7390] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 03/12/2021] [Indexed: 05/08/2023]
Abstract
RNA-based therapies offer unique advantages for treating brain tumors. However, tumor penetrance and uptake are hampered by RNA therapeutic size, charge, and need to be "packaged" in large carriers to improve bioavailability. Here, we have examined delivery of siRNA, packaged in 50-nm cationic lipid-polymer hybrid nanoparticles (LPHs:siRNA), combined with microbubble-enhanced focused ultrasound (MB-FUS) in pediatric and adult preclinical brain tumor models. Using single-cell image analysis, we show that MB-FUS in combination with LPHs:siRNA leads to more than 10-fold improvement in siRNA delivery into brain tumor microenvironments of the two models. MB-FUS delivery of Smoothened (SMO) targeting siRNAs reduces SMO protein production and markedly increases tumor cell death in the SMO-activated medulloblastoma model. Moreover, our analysis reveals that MB-FUS and nanoparticle properties can be optimized to maximize delivery in the brain tumor microenvironment, thereby serving as a platform for developing next-generation tunable delivery systems for RNA-based therapy in brain tumors.
Collapse
Affiliation(s)
- Yutong Guo
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Hohyun Lee
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Zhou Fang
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Anastasia Velalopoulou
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Jinhwan Kim
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Midhun Ben Thomas
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - Jingbo Liu
- Department of Pediatrics, Aflac Cancer and Blood, Emory University School of Medicine, Atlanta, GA, USA
| | - Ryan G Abramowitz
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - YongTae Kim
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Ahmet F Coskun
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Daniel Pomeranz Krummel
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Soma Sengupta
- Department of Neurology and Rehabilitation Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Tobey J MacDonald
- Department of Pediatrics, Aflac Cancer and Blood, Emory University School of Medicine, Atlanta, GA, USA
| | - Costas Arvanitis
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA.
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| |
Collapse
|
94
|
Delpire E. Advances in the development of novel compounds targeting cation-chloride cotransporter physiology. Am J Physiol Cell Physiol 2021; 320:C324-C340. [PMID: 33356948 PMCID: PMC8294628 DOI: 10.1152/ajpcell.00566.2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 01/05/2023]
Abstract
For about half a century, the pharmacology of electroneutral cation-chloride cotransporters has been dominated by a few drugs that are widely used in clinical medicine. Because these diuretic drugs are so good at what they do, there has been little incentive in expanding their pharmacology. The increasing realization that cation-chloride cotransporters are involved in many other key physiological processes and the knowledge that different tissues express homologous proteins with matching transport functions have rekindled interest in drug discovery. This review summarizes the methods available to assess the function of these transporters and describe the multiple efforts that have made to identify new compounds. We describe multiple screens targeting KCC2 function and one screen designed to find compounds that discriminate between NKCC1 and NKCC2. Two of the KCC2 screens identified new inhibitors that are 3-4 orders of magnitude more potent than furosemide. Additional screens identified compounds that purportedly increase cell surface expression of the cotransporter, as well as several FDA-approved drugs that increase KCC2 transcription and expression. The technical details of each screen biased them toward specific processes in the life cycle of the transporter, making these efforts independent and complementary. In addition, each drug discovery effort contributes to our understanding of the biology of the cotransporters.
Collapse
Affiliation(s)
- Eric Delpire
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee
| |
Collapse
|
95
|
Semin BК, Davletshina LN, Goryachev SN, Seibert M. Ca 2+ effects on Fe(II) interactions with Mn-binding sites in Mn-depleted oxygen-evolving complexes of photosystem II and on Fe replacement of Mn in Mn-containing, Ca-depleted complexes. Photosynth Res 2021; 147:229-237. [PMID: 33532973 DOI: 10.1007/s11120-020-00813-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
Fe(II) cations bind with high efficiency and specificity at the high-affinity (HA), Mn-binding site (termed the "blocking effect" since Fe blocks further electron donation to the site) of the oxygen-evolving complex (OEC) in Mn-depleted, photosystem II (PSII) membrane fragments (Semin et al. in Biochemistry 41:5854, 2002). Furthermore, Fe(II) cations can substitute for 1 or 2Mn cations (pH dependent) in Ca-depleted PSII membranes (Semin et al. in Journal of Bioenergetics and Biomembranes 48:227, 2016; Semin et al. in Journal of Photochemistry and Photobiology B 178:192, 2018). In the current study, we examined the effect of Ca2+ cations on the interaction of Fe(II) ions with Mn-depleted [PSII(-Mn)] and Ca-depleted [PSII(-Ca)] photosystem II membranes. We found that Ca2+ cations (about 50 mM) inhibit the light-dependent oxidation of Fe(II) (5 µM) by about 25% in PSII(-Mn) membranes, whereas inhibition of the blocking process is greater at about 40%. Blocking of the HA site by Fe cations also decreases the rate of charge recombination between QA- and YZ•+ from t1/2 = 30 ms to 46 ms. However, Ca2+ does not affect the rate during the blocking process. An Fe(II) cation (20 µM) replaces 1Mn cation in the Mn4CaO5 catalytic cluster of PSII(-Ca) membranes at pH 5.7 but 2 Mn cations at pH 6.5. In the presence of Ca2+ (10 mM) during the substitution process, Fe(II) is not able to extract Mn at pH 5.7 and extracts only 1Mn at pH 6.5 (instead of two without Ca2+). Measurements of fluorescence induction kinetics support these observations. Inhibition of Mn substitution with Fe(II) cations in the OEC only occurs with Ca2+ and Sr2+ cations, which are also able to restore oxygen evolution in PSII(-Ca) samples. Nonactive cations like La3+, Ni2+, Cd2+, and Mg2+ have no influence on the replacement of Mn with Fe. These results show that the location and/or ligand composition of one Mn cation in the Mn4CaO5 cluster is strongly affected by calcium depletion or rebinding and that bound calcium affects the redox potential of the extractable Mn4 cation in the OEC, making it resistant to reduction.
Collapse
Affiliation(s)
- B К Semin
- Department of Biophysics, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234.
| | - L N Davletshina
- Department of Biophysics, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - S N Goryachev
- Department of Biophysics, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia, 119234
| | - M Seibert
- Laboratory, BioEnergy Sciences and Technology Directorate, National Renewable Energy, Golden, CO, 80401, USA
| |
Collapse
|
96
|
Takehana S, Murata Y, Jo JI, Tabata Y. Complexation design of cationized gelatin and molecular beacon to visualize intracellular mRNA. PLoS One 2021; 16:e0245899. [PMID: 33493232 PMCID: PMC7833158 DOI: 10.1371/journal.pone.0245899] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 12/22/2020] [Indexed: 12/12/2022] Open
Abstract
The objective of this study is to prepare cationized gelatin-molecular beacon (MB) complexes for the visualization of intracellular messenger RNA (mRNA). The complexes were prepared from cationized gelatins with different extents of cationization and different mixing ratios of MB to cationized gelatin. The apparent size of complexes was almost similar, while the zeta potential was different among the complexes. Irrespective of the preparation conditions, the complexes had a sequence specificity against the target oligonucleotides in hybridization. The cytotoxicity and the amount of complexes internalized into cells increased with an increase in the cationization extent and the concentration of cationized gelatin. After the incubation with complexes prepared from cationized gelatin with the highest extent of cationization and at mixing ratios of 10 and 20 pmole MB/μg cationized gelatin, a high fluorescent intensity was detected. On the other hand, the complex prepared with the mixing ratio at 20 pmole/μg did not show any cytotoxicity. The complex was the most effective to visualize the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA endogenously present. In addition, even for enhanced green fluorescent protein (EGFP) mRNA exogenously transfected, the complex permitted to effectively detect it as well. It is concluded that both the endogenous and exogenous mRNA can be visualized in living cells by use of cationized gelatin-MB complexes designed.
Collapse
Affiliation(s)
- Sho Takehana
- Laboratory of Biomaterials, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Yuki Murata
- Laboratory of Biomaterials, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Jun-ichiro Jo
- Laboratory of Biomaterials, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Yasuhiko Tabata
- Laboratory of Biomaterials, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
- * E-mail:
| |
Collapse
|
97
|
Zhu X, Li Q, Song W, Peng X, Zhao R. P2X7 receptor: a critical regulator and potential target for breast cancer. J Mol Med (Berl) 2021; 99:349-358. [PMID: 33486566 DOI: 10.1007/s00109-021-02041-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 01/13/2021] [Accepted: 01/14/2021] [Indexed: 12/24/2022]
Abstract
Breast cancer is currently the most common cancer and the leading cause of cancer death among women worldwide. Advanced breast cancer is prone to metastasis, and there is currently no drug to cure metastatic breast cancer. The purinergic ligand-gated ion channel 7 receptor is an ATP-gated nonselective cation channel receptor and is involved in signal transduction, growth regulation, cytokine secretion, and tumor cell development. Recent studies have shown that upregulation of the P2X7 receptor in breast cancer can mediate AKT signaling pathways, Ca2 þ-activated SK3 potassium channels, and EMT and regulate the secretion of small extracellular vesicles to promote breast cancer invasion and migration, which are affected by factors such as hypoxia and ATP. In addition, studies have shown that microRNAs can bind to the 3' untranslated region of the P2X7 receptor, which affects the occurrence and development of breast cancer by upregulating and downregulating P2X7 receptor expression. Studies have shown that new P2X7 receptor inhibitors, such as emodin and Uncaria tomentosa, can inhibit P2X7 receptor-mediated breast cancer invasion and are expected to be used clinically. This article reviews the research progress on the relationship between the P2X7 receptor and breast cancer to provide new ideas and a basis for clinical diagnosis and treatment.
Collapse
Affiliation(s)
- Xiaodi Zhu
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, China
| | - Qianqian Li
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, China
| | - Wei Song
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, China
| | - Xiaoxiang Peng
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, China.
| | - Ronglan Zhao
- School of Medical Laboratory, Weifang Medical University, Weifang, Shandong, China.
| |
Collapse
|
98
|
Bruno J, Edwards JC. Kidney-disease-associated variants of Apolipoprotein L1 show gain of function in cation channel activity. J Biol Chem 2021; 296:100238. [PMID: 33380423 PMCID: PMC7948812 DOI: 10.1074/jbc.ra120.013943] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 12/23/2020] [Accepted: 12/30/2020] [Indexed: 11/08/2022] Open
Abstract
Variants in Apolipoprotein L1 (ApoL1) are known to be responsible for increased risk of some progressive kidney diseases among people of African ancestry. ApoL1 is an amphitropic protein that can insert into phospholipid membranes and confer anion- or cation-selective permeability to phospholipid membranes depending on pH. Whether these activities differ among the variants or whether they contribute to disease pathogenesis is unknown. We used assays of voltage-driven ion flux from phospholipid vesicles and of stable membrane association to assess differences among ApoL1 isoforms. There is a significant (approximately twofold) increase in the cation-selective ion permease activity of the two kidney-disease-associated variants compared with the reference protein. In contrast, we find no difference in the anion-selective permease activity at low pH among the isoforms. Compared with the reference sequence, the two disease-associated variants show increased stable association with phospholipid vesicles under conditions that support the cation permease activity, suggesting that the increased activity may be due to more efficient membrane association and insertion. There is no difference in membrane association among isoforms under optimal conditions for the anion permease activity. These data support a model in which enhanced cation permeability may contribute to the progressive kidney diseases associated with high-risk ApoL1 alleles.
Collapse
Affiliation(s)
- Jonathan Bruno
- Nephrology Division, Department of Internal Medicine, Saint Louis University, St Louis, Missouri, USA
| | - John C Edwards
- Nephrology Division, Department of Internal Medicine, Saint Louis University, St Louis, Missouri, USA.
| |
Collapse
|
99
|
Modareszadeh M, Bahmani R, Kim D, Hwang S. CAX3 (cation/proton exchanger) mediates a Cd tolerance by decreasing ROS through Ca elevation in Arabidopsis. Plant Mol Biol 2021; 105:115-132. [PMID: 32926249 DOI: 10.1007/s11103-020-01072-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
KEY MESSAGE Over-expression of CAX3 encoding a cation/proton exchanger enhances Cd tolerance by decreasing ROS (Reactive Oxygen Species) through activating anti-oxidative enzymes via elevation of Ca level in Arabidopsis CAXs (cation/proton exchangers) are involved in the sequestration of cations such as Mn, Li, and Cd, as well as Ca, from cytosol into the vacuole using proton gradients. In addition, it has been reported that CAX1, 2 and 4 are involved in Cd tolerance. Interestingly, it has been reported that CAX3 expressions were enhanced by Cd in Cd-tolerant transgenic plants expressing Hb1 (hemoglobin 1) or UBC1 (Ub-conjugating enzyme 1). Therefore, to investigate whether CAX3 plays a role in increasing Cd tolerance, CAX3 of Arabidopsis and tobacco were over-expressed in Arabidopsis thaliana. Compared to control plants, both transgenic plants displayed an increase in Cd tolerance, no change in Cd accumulation, and enhanced Ca levels. In support of these, AtCAX3-Arabidopsis showed no change in expressions of Cd transporters, but reduced expressions of Ca exporters and lower rate of Ca efflux. By contrast, atcax3 knockout Arabidopsis exhibited a reduced Cd tolerance, while the Cd level was not altered. The expression of Δ90-AtCAX3 (deletion of autoinhibitory domain) increased Cd and Ca tolerance in yeast, while AtCAX3 expression did not. Interestingly, less accumulation of ROS (H2O2 and O2-) was observed in CAX3-expressing transgenic plants and was accompanied with higher antioxidant enzyme activities (SOD, CAT, GR). Taken together, CAX3 over-expression may enhance Cd tolerance by decreasing Cd-induced ROS production by activating antioxidant enzymes and by intervening the positive feedback circuit between ROS generation and Cd-induced spikes of cytoplasmic Ca.
Collapse
Affiliation(s)
- Mahsa Modareszadeh
- Department of Molecular Biology, Sejong University, Seoul, 143-747, Republic of Korea
- Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, Republic of Korea
- Plant Engineering Research Institute, Sejong University, Seoul, 143-747, Republic of Korea
| | - Ramin Bahmani
- Department of Molecular Biology, Sejong University, Seoul, 143-747, Republic of Korea
- Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, Republic of Korea
- Plant Engineering Research Institute, Sejong University, Seoul, 143-747, Republic of Korea
| | - DongGwan Kim
- Department of Molecular Biology, Sejong University, Seoul, 143-747, Republic of Korea
- Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, Republic of Korea
- Plant Engineering Research Institute, Sejong University, Seoul, 143-747, Republic of Korea
| | - Seongbin Hwang
- Department of Molecular Biology, Sejong University, Seoul, 143-747, Republic of Korea.
- Department of Bioindustry and Bioresource Engineering, Sejong University, Seoul, 143-747, Republic of Korea.
- Plant Engineering Research Institute, Sejong University, Seoul, 143-747, Republic of Korea.
| |
Collapse
|
100
|
Wang Y, Ying J, Zhang Y, Xu L, Zhang W, Ni M, Zhu Y, Liu L. Genome-Wide Identification and Functional Characterization of the Cation Proton Antiporter (CPA) Family Related to Salt Stress Response in Radish ( Raphanus sativus L.). Int J Mol Sci 2020; 21:E8262. [PMID: 33158201 PMCID: PMC7662821 DOI: 10.3390/ijms21218262] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 01/04/2023] Open
Abstract
The CPA (cation proton antiporter) family plays an essential role during plant stress tolerance by regulating ionic and pH homeostasis of the cell. Radish fleshy roots are susceptible to abiotic stress during growth and development, especially salt stress. To date, CPA family genes have not yet been identified in radish and the biological functions remain unclear. In this study, 60 CPA candidate genes in radish were identified on the whole genome level, which were divided into three subfamilies including the Na+/H+ exchanger (NHX), K+ efflux antiporter (KEA), and cation/H+ exchanger (CHX) families. In total, 58 of the 60 RsCPA genes were localized to the nine chromosomes. RNA-seq. data showed that 60 RsCPA genes had various expression levels in the leaves, roots, cortex, cambium, and xylem at different development stages, as well as under different abiotic stresses. RT-qPCR analysis indicated that all nine RsNHXs genes showed up regulated trends after 250 mM NaCl exposure at 3, 6, 12, and 24h. The RsCPA31 (RsNHX1) gene, which might be the most important members of the RsNHX subfamily, exhibited obvious increased expression levels during 24h salt stress treatment. Heterologous over-and inhibited-expression of RsNHX1 in Arabidopsis showed that RsNHX1 had a positive function in salt tolerance. Furthermore, a turnip yellow mosaic virus (TYMV)-induced gene silence (VIGS) system was firstly used to functionally characterize the candidate gene in radish, which showed that plant with the silence of endogenous RsNHX1 was more susceptible to the salt stress. According to our results we provide insights into the complexity of the RsCPA gene family and a valuable resource to explore the potential functions of RsCPA genes in radish.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Yuelin Zhu
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China; (Y.W.); (J.Y.); (Y.Z.); (L.X.); (W.Z.); (M.N.)
| | - Liwang Liu
- National Key Laboratory of Crop Genetics and Germplasm Enhancement, Key Laboratory of Horticultural Crop Biology and Genetic Improvement (East China) of MOAR, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China; (Y.W.); (J.Y.); (Y.Z.); (L.X.); (W.Z.); (M.N.)
| |
Collapse
|