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Alsubeeh NA, Almuqbil MA, Davies W, Bertoli-Avella A, Anikar S, Zonic E, Eyaid WM. CCDC47 gene and trichohepatoneurodevelopmental syndrome: Report of the fifth and sixth cases from Saudi Arabia. Am J Med Genet A 2024:e63784. [PMID: 39171352 DOI: 10.1002/ajmg.a.63784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 05/19/2024] [Accepted: 05/30/2024] [Indexed: 08/23/2024]
Abstract
Trichohepatoneurodevelopmental syndrome (THNS) is an ultra-rare and complex disorder affecting multiple organ systems. It is characterized by liver dysfunction, hypotonia, global developmental delay, coarse hair, and dysmorphic features. We describe two cases of THNS of Saudi origin, the fifth and sixth cases in the medical literature. Both cases presented with multiple dysmorphic features, generalized hypotonia, global developmental delay, and high liver enzyme level. Exome sequencing of Case 1 identified a pathogenic homozygous variant within the CCDC47: NM_020198.2:c.567_570del, p.(Glu190Profs*7). Genome sequencing of Case 2 identified two likely pathogenic heterozygous variants within the CCDC47: NM_020198.2:c.1327C>T, p.(Arg443*) and NM_020198.2:c.422dup, p.(Leu141Phefs*19). The trans phase of the detected variants has been confirmed by the parental testing. Furthermore, we evaluated the gene-disease association as per ClinGen guidelines and reached a strong level of association after inclusion of the new patients/variants. The findings from these cases will help to delineate the clinical phenotype and the mutational spectrum of this complex disorder.
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Affiliation(s)
| | - Mohammed A Almuqbil
- Department of Pediatrics, King Abdullah Specialist Children's Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- College of Medicine, King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
| | - William Davies
- Division of Psychological Medicine and Clinical Neurosciences and Centre for Neuropsychiatric Genetics, Schools of Medicine and Psychology, Cardiff University, Cardiff, UK
| | | | | | | | - Wafaa M Eyaid
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- College of Medicine, King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- Genetics and Precision Medicine Department, King Abdullah Specialist Children's Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
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2
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Yang Q, Zhou X, Ling Y, Zhang Q, Yi S, Chen Q, Zhang S, Qin Z, Luo J. Clinical and genetic analysis of trichohepatoneurodevelopmental syndrome caused by a CCDC47 variant. Heliyon 2024; 10:e27955. [PMID: 38524542 PMCID: PMC10958427 DOI: 10.1016/j.heliyon.2024.e27955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 03/06/2024] [Accepted: 03/08/2024] [Indexed: 03/26/2024] Open
Abstract
Trichohepatoneurodevelopmental syndrome is an extremely uncommon autosomal recessive disorder resulting from variants in the CCDC47 gene, which encodes a Ca2+-binding endoplasmic reticulum (ER) transmembrane protein. To date, only four patients with CCDC47 deficiency have been reported, all of them with homozygous truncating CCDC47 variants. For this study, a Chinese family was recruited, which included a patient diagnosed with trichohepatoneurodevelopmental syndrome. Whole exome sequencing (WES) identified the proband's novel homozygous CCDC47 variation (NM_020198: c.634C > T(p.Arg212*). The variant was confirmed to be segregating in the proband and her unaffected relatives through Sanger sequencing. The patient described exhibited a clinical phenotype similar to that of patients with the CCDC47 variant. Compared to reported cases with CCDC47 pathogenic variants, our patients showed a novel complication of hearing impairment. In addition, brain abnormalities, small feet, bilateral hip dislocation, hip dysplasia, overlapping toes, pectus excavatum, scoliosis and narrow chest were not observed in our patient. We also examined five different variations and their corresponding phenotypes from five patients, both in current and previous research. Although some clinical manifestations of trichohepatoneurodevelopmental syndrome were highly variable, the most common phenotypes observed in these patients include microcephaly, profound intellectual disability, severe global development delay, pronounced growth restriction, hypotonia, woolly hair, facial dysmorphism, respiratory and visual abnormalities, gastrointestinal abnormalities, liver dysfunction, pruritus, skeletal and limb abnormalities, congenital heart defects and immunodeficiency. The present report is the first of a Chinese infant with homozygous variant in the CCDC47 gene. We expanded the genetic and phenotypic spectrum associated with trichohepatoneurodevelopmental syndrome.
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Affiliation(s)
- Qi Yang
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Xunzhao Zhou
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Yeying Ling
- Department of Neonatal Intensive Care Unit, Neonatal Medical Center, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Qiang Zhang
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Shang Yi
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Qiuli Chen
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Shujie Zhang
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Zailong Qin
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
| | - Jingsi Luo
- Guangxi Key Laboratory of Birth Defects Research and Prevention, Guangxi Key Laboratory of Reproductive Health and Birth Defects Prevention, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
- Department of Genetic and Metabolic Central Laboratory, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning, China
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3
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Groenendyk J, Michalak M. Interplay between calcium and endoplasmic reticulum stress. Cell Calcium 2023; 113:102753. [PMID: 37209448 DOI: 10.1016/j.ceca.2023.102753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/22/2023]
Abstract
Cellular homeostasis is crucial for the healthy functioning of the organism. Disruption of cellular homeostasis activates endoplasmic reticulum (ER) stress coping responses including the unfolded protein response (UPR). There are three ER resident stress sensors responsible for UPR activation - IRE1α, PERK and ATF6. Ca2+ signaling plays an important role in stress responses including the UPR and the ER is the main Ca2+ storage organelle and a source of Ca2+ for cell signaling. The ER contains many proteins involved in Ca2+ import/export/ storage, Ca2+ movement between different cellular organelles and ER Ca2+ stores refilling. Here we focus on selected aspects of ER Ca2+ homeostasis and its role in activation of the ER stress coping responses.
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Affiliation(s)
- Jody Groenendyk
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2H7, Canada.
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O'Keefe S, Pool MR, High S. Membrane protein biogenesis at the ER: the highways and byways. FEBS J 2022; 289:6835-6862. [PMID: 33960686 DOI: 10.1111/febs.15905] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/19/2021] [Accepted: 04/28/2021] [Indexed: 01/13/2023]
Abstract
The Sec61 complex is the major protein translocation channel of the endoplasmic reticulum (ER), where it plays a central role in the biogenesis of membrane and secretory proteins. Whilst Sec61-mediated protein translocation is typically coupled to polypeptide synthesis, suggestive of significant complexity, an obvious characteristic of this core translocation machinery is its surprising simplicity. Over thirty years after its initial discovery, we now understand that the Sec61 complex is in fact the central piece of an elaborate jigsaw puzzle, which can be partly solved using new research findings. We propose that the Sec61 complex acts as a dynamic hub for co-translational protein translocation at the ER, proactively recruiting a range of accessory complexes that enhance and regulate its function in response to different protein clients. It is now clear that the Sec61 complex does not have a monopoly on co-translational insertion, with some transmembrane proteins preferentially utilising the ER membrane complex instead. We also have a better understanding of post-insertion events, where at least one membrane-embedded chaperone complex can capture the newly inserted transmembrane domains of multi-span proteins and co-ordinate their assembly into a native structure. Having discovered this array of Sec61-associated components and competitors, our next challenge is to understand how they act together in order to expand the range and complexity of the membrane proteins that can be synthesised at the ER. Furthermore, this diversity of components and pathways may open up new opportunities for targeted therapeutic interventions designed to selectively modulate protein biogenesis at the ER.
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Affiliation(s)
- Sarah O'Keefe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, UK
| | - Martin R Pool
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, UK
| | - Stephen High
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, UK
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5
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Biological Effects of Transforming Growth Factor Beta in Human Cholangiocytes. BIOLOGY 2022; 11:biology11040566. [PMID: 35453765 PMCID: PMC9033039 DOI: 10.3390/biology11040566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/30/2022] [Accepted: 04/05/2022] [Indexed: 11/17/2022]
Abstract
TGF-β is a cytokine implicated in multiple cellular responses, including cell cycle regulation, fibrogenesis, angiogenesis and immune modulation. In response to pro-inflammatory and chemotactic cytokines and growth factors, cholangiocytes prime biliary damage, characteristic of cholangiopathies and pathologies that affect biliary tree. The effects and signaling related to TGF-β in cholangiocyte remains poorly investigated. In this study, the cellular response of human cholangiocytes to TGF-β was examined. Wound-healing assay, proliferation assay and cell cycle analyses were used to monitor the changes in cholangiocyte behavior following 24 and 48 h of TGF-β stimulation. Moreover, proteomic approach was used to identify proteins modulated by TGF-β treatment. Our study highlighted a reduction in cholangiocyte proliferation and a cell cycle arrest in G0/G1 phase following TGF-β treatment. Moreover, proteomic analysis allowed the identification of four downregulated proteins (CaM kinase II subunit delta, caveolin-1, NipSnap1 and calumin) involved in Ca2+ homeostasis. Accordingly, Gene Ontology analysis highlighted that the plasma membrane and endoplasmic reticulum are the cellular compartments most affected by TGF-β. These results suggested that the effects of TGF-β in human cholangiocytes could be related to an imbalance of intracellular calcium homeostasis. In addition, for the first time, we correlated calumin and NipSnap1 to TGF-β signaling.
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Tirincsi A, Sicking M, Hadzibeganovic D, Haßdenteufel S, Lang S. The Molecular Biodiversity of Protein Targeting and Protein Transport Related to the Endoplasmic Reticulum. Int J Mol Sci 2021; 23:143. [PMID: 35008565 PMCID: PMC8745461 DOI: 10.3390/ijms23010143] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 12/15/2022] Open
Abstract
Looking at the variety of the thousands of different polypeptides that have been focused on in the research on the endoplasmic reticulum from the last five decades taught us one humble lesson: no one size fits all. Cells use an impressive array of components to enable the safe transport of protein cargo from the cytosolic ribosomes to the endoplasmic reticulum. Safety during the transit is warranted by the interplay of cytosolic chaperones, membrane receptors, and protein translocases that together form functional networks and serve as protein targeting and translocation routes. While two targeting routes to the endoplasmic reticulum, SRP (signal recognition particle) and GET (guided entry of tail-anchored proteins), prefer targeting determinants at the N- and C-terminus of the cargo polypeptide, respectively, the recently discovered SND (SRP-independent) route seems to preferentially cater for cargos with non-generic targeting signals that are less hydrophobic or more distant from the termini. With an emphasis on targeting routes and protein translocases, we will discuss those functional networks that drive efficient protein topogenesis and shed light on their redundant and dynamic nature in health and disease.
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Affiliation(s)
- Andrea Tirincsi
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
| | - Mark Sicking
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
| | - Drazena Hadzibeganovic
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
| | - Sarah Haßdenteufel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sven Lang
- Department of Medical Biochemistry and Molecular Biology, Saarland University, 66421 Homburg, Germany; (A.T.); (M.S.); (D.H.)
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7
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Priyanka PP, Yenugu S. Coiled-Coil Domain-Containing (CCDC) Proteins: Functional Roles in General and Male Reproductive Physiology. Reprod Sci 2021; 28:2725-2734. [PMID: 33942254 DOI: 10.1007/s43032-021-00595-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 04/22/2021] [Indexed: 01/10/2023]
Abstract
The coiled-coil domain-containing (CCDC) proteins have been implicated in a variety of physiological and pathological processes. Their functional roles vary from their interaction with molecular components of signaling pathways to determining the physiological functions at the cellular and organ level. Thus, they govern important functions like gametogenesis, embryonic development, hematopoiesis, angiogenesis, and ciliary development. Further, they are implicated in the pathogenesis of a large number of cancers. Polymorphisms in CCDC genes are associated with the risk of lifetime diseases. Because of their role in many biological processes, they have been extensively studied. This review concisely presents the functional role of CCDC proteins that have been studied in the last decade. Studies on CCDC proteins continue to be an active area of investigation because of their indispensable functions. However, there is ample opportunity to further understand the involvement of CCDC proteins in many more functions. It is anticipated that basing on the available literature, the functional role of CCDC proteins will be explored much further.
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Affiliation(s)
| | - Suresh Yenugu
- Department of Animal Biology, University of Hyderabad, Hyderabad, 500046, India.
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Nam YW, Kong D, Wang D, Orfali R, Sherpa RT, Totonchy J, Nauli SM, Zhang M. Differential modulation of SK channel subtypes by phosphorylation. Cell Calcium 2021; 94:102346. [PMID: 33422768 PMCID: PMC8415101 DOI: 10.1016/j.ceca.2020.102346] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/23/2020] [Accepted: 12/23/2020] [Indexed: 01/01/2023]
Abstract
Small-conductance Ca2+-activated K+ (SK) channels are voltage-independent and are activated by Ca2+ binding to the calmodulin constitutively associated with the channels. Both the pore-forming subunits and the associated calmodulin are subject to phosphorylation. Here, we investigated the modulation of different SK channel subtypes by phosphorylation, using the cultured endothelial cells as a tool. We report that casein kinase 2 (CK2) negatively modulates the apparent Ca2+ sensitivity of SK1 and IK channel subtypes by more than 5-fold, whereas the apparent Ca2+ sensitivity of the SK3 and SK2 subtypes is only reduced by ∼2-fold, when heterologously expressed on the plasma membrane of cultured endothelial cells. The SK2 channel subtype exhibits limited cell surface expression in these cells, partly as a result of the phosphorylation of its C-terminus by cyclic AMP-dependent protein kinase (PKA). SK2 channels expressed on the ER and mitochondria membranes may protect against cell death. This work reveals the subtype-specific modulation of the apparent Ca2+ sensitivity and subcellular localization of SK channels by phosphorylation in cultured endothelial cells.
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Affiliation(s)
- Young-Woo Nam
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Dezhi Kong
- Institute of Chinese Integrative Medicine, Hebei Medical University, Shijiazhuang, Hebei, 050017, China
| | - Dong Wang
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Razan Orfali
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Rinzhin T Sherpa
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Jennifer Totonchy
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Surya M Nauli
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Miao Zhang
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA.
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9
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PAT in the ER for Transmembrane Protein Folding. Trends Biochem Sci 2020; 45:1007-1008. [DOI: 10.1016/j.tibs.2020.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 10/02/2020] [Indexed: 11/21/2022]
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10
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McGilvray PT, Anghel SA, Sundaram A, Zhong F, Trnka MJ, Fuller JR, Hu H, Burlingame AL, Keenan RJ. An ER translocon for multi-pass membrane protein biogenesis. eLife 2020; 9:e56889. [PMID: 32820719 PMCID: PMC7505659 DOI: 10.7554/elife.56889] [Citation(s) in RCA: 78] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 08/20/2020] [Indexed: 12/23/2022] Open
Abstract
Membrane proteins with multiple transmembrane domains play critical roles in cell physiology, but little is known about the machinery coordinating their biogenesis at the endoplasmic reticulum. Here we describe a ~ 360 kDa ribosome-associated complex comprising the core Sec61 channel and five accessory factors: TMCO1, CCDC47 and the Nicalin-TMEM147-NOMO complex. Cryo-electron microscopy reveals a large assembly at the ribosome exit tunnel organized around a central membrane cavity. Similar to protein-conducting channels that facilitate movement of transmembrane segments, cytosolic and luminal funnels in TMCO1 and TMEM147, respectively, suggest routes into the central membrane cavity. High-throughput mRNA sequencing shows selective translocon engagement with hundreds of different multi-pass membrane proteins. Consistent with a role in multi-pass membrane protein biogenesis, cells lacking different accessory components show reduced levels of one such client, the glutamate transporter EAAT1. These results identify a new human translocon and provide a molecular framework for understanding its role in multi-pass membrane protein biogenesis.
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Affiliation(s)
- Philip T McGilvray
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
| | - S Andrei Anghel
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
- Department of Molecular Genetics and Cell Biology, The University of ChicagoChicagoUnited States
| | - Arunkumar Sundaram
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
| | - Frank Zhong
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
- Department of Molecular Genetics and Cell Biology, The University of ChicagoChicagoUnited States
| | - Michael J Trnka
- Department of Pharmaceutical Chemistry, University of California, San FranciscoSan FranciscoUnited States
| | - James R Fuller
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
| | - Hong Hu
- Center for Research Informatics, The University of ChicagoChicagoUnited States
| | - Alma L Burlingame
- Department of Pharmaceutical Chemistry, University of California, San FranciscoSan FranciscoUnited States
| | - Robert J Keenan
- Department of Biochemistry and Molecular Biology, The University of ChicagoChicagoUnited States
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Morimoto M, Waller-Evans H, Ammous Z, Song X, Strauss KA, Pehlivan D, Gonzaga-Jauregui C, Puffenberger EG, Holst CR, Karaca E, Brigatti KW, Maguire E, Coban-Akdemir ZH, Amagata A, Lau CC, Chepa-Lotrea X, Macnamara E, Tos T, Isikay S, Nehrebecky M, Overton JD, Klein M, Markello TC, Posey JE, Adams DR, Lloyd-Evans E, Lupski JR, Gahl WA, Malicdan MCV. Bi-allelic CCDC47 Variants Cause a Disorder Characterized by Woolly Hair, Liver Dysfunction, Dysmorphic Features, and Global Developmental Delay. Am J Hum Genet 2018; 103:794-807. [PMID: 30401460 PMCID: PMC6218603 DOI: 10.1016/j.ajhg.2018.09.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/26/2018] [Indexed: 01/06/2023] Open
Abstract
Ca2+ signaling is vital for various cellular processes including synaptic vesicle exocytosis, muscle contraction, regulation of secretion, gene transcription, and cellular proliferation. The endoplasmic reticulum (ER) is the largest intracellular Ca2+ store, and dysregulation of ER Ca2+ signaling and homeostasis contributes to the pathogenesis of various complex disorders and Mendelian disease traits. We describe four unrelated individuals with a complex multisystem disorder characterized by woolly hair, liver dysfunction, pruritus, dysmorphic features, hypotonia, and global developmental delay. Through whole-exome sequencing and family-based genomics, we identified bi-allelic variants in CCDC47 that encodes the Ca2+-binding ER transmembrane protein CCDC47. CCDC47, also known as calumin, has been shown to bind Ca2+ with low affinity and high capacity. In mice, loss of Ccdc47 leads to embryonic lethality, suggesting that Ccdc47 is essential for early development. Characterization of cells from individuals with predicted likely damaging alleles showed decreased CCDC47 mRNA expression and protein levels. In vitro cellular experiments showed decreased total ER Ca2+ storage, impaired Ca2+ signaling mediated by the IP3R Ca2+ release channel, and reduced ER Ca2+ refilling via store-operated Ca2+ entry. These results, together with the previously described role of CCDC47 in Ca2+ signaling and development, suggest that bi-allelic loss-of-function variants in CCDC47 underlie the pathogenesis of this multisystem disorder.
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Affiliation(s)
- Marie Morimoto
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Zineb Ammous
- The Community Health Clinic, Topeka, IN 46571, USA
| | - Xiaofei Song
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | | | - Charles R Holst
- BioElectron Technology Corporation, Mountain View, CA 94043, USA
| | - Ender Karaca
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Emily Maguire
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - Zeynep H Coban-Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Akiko Amagata
- BioElectron Technology Corporation, Mountain View, CA 94043, USA
| | - C Christopher Lau
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xenia Chepa-Lotrea
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ellen Macnamara
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tulay Tos
- Department of Medical Genetics, Dr. Sami Ulus Research and Training Hospital of Women's and Children's Health and Diseases, Ankara 06080, Turkey
| | - Sedat Isikay
- Department of Physiotherapy and Rehabilitation, Hasan Kalyoncu University, School of Health Sciences, Gaziantep 27000, Turkey
| | - Michele Nehrebecky
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA
| | - John D Overton
- Regeneron Genetics Center, Regeneron Pharmaceuticals Inc., Tarrytown, NY 10591, USA
| | - Matthew Klein
- BioElectron Technology Corporation, Mountain View, CA 94043, USA
| | - Thomas C Markello
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - David R Adams
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA; Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA; Texas Children's Hospital, Houston, TX 77030, USA
| | - William A Gahl
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA; Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - May Christine V Malicdan
- National Institutes of Health Undiagnosed Diseases Program, Common Fund, Office of the Director, National Institutes of Health, Bethesda, MD 20892, USA; Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Thapa K, Wu KC, Sarma A, Grund EM, Szeto A, Mendez AJ, Gesta S, Vishnudas VK, Narain NR, Sarangarajan R. Dysregulation of the calcium handling protein, CCDC47, is associated with diabetic cardiomyopathy. Cell Biosci 2018; 8:45. [PMID: 30140426 PMCID: PMC6098598 DOI: 10.1186/s13578-018-0244-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 08/11/2018] [Indexed: 11/10/2022] Open
Abstract
Background Diabetes mellitus is associated with an increased risk in diabetic cardiomyopathy (DCM) that is distinctly not attributed to co-morbidities with other vasculature diseases. To date, while dysregulation of calcium handling is a key hallmark in cardiomyopathy, studies have been inconsistent in the types of alterations involved. In this study human cardiomyocytes were exposed to an environmental nutritional perturbation of high glucose, fatty acids, and l-carnitine to model DCM and iTRAQ-coupled LC–MS/MS proteomic analysis was used to capture proteins affected by the perturbation. The proteins captured were then compared to proteins currently annotated in the cardiovascular disease (CVD) gene ontology (GO) database to identify proteins not previously described as being related to CVD. Subsequently, GO analysis for calcium regulating proteins and endoplasmic/sarcoplasmic reticulum (ER/SR) associated proteins was carried out. Results Here, we identified CCDC47 (calumin) as a unique calcium regulating protein altered in our in vitro nutritional perturbation model. The cellular and functional role of CCDC47 was then assessed in rat cardiomyocytes. In rat H9C2 myocytes, overexpression of CCDC47 resulted in increase in ionomycin-induced calcium release and reuptake. Of interest, in a diet-induced obese (DIO) rat model of DCM, CCDC47 mRNA expression was increased in the atrium and ventricle of the heart, but CCDC47 protein expression was significantly increased only in the atrium of DIO rats compared to lean control rats. Notably, no changes in ANP, BNP, or β-MHC were observed between DIO rats and lean control rats. Conclusions Together, our in vitro and in vivo studies demonstrate that CCDC47 is a unique calcium regulating protein that is associated with early onset hypertrophic cardiomyopathy. Electronic supplementary material The online version of this article (10.1186/s13578-018-0244-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Khampaseuth Thapa
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
| | - Kai Connie Wu
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
| | - Aishwarya Sarma
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
| | - Eric M Grund
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
| | - Angela Szeto
- 2Diabetes Research Institute, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Armando J Mendez
- 2Diabetes Research Institute, University of Miami Miller School of Medicine, Miami, FL 33136 USA
| | - Stephane Gesta
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
| | - Vivek K Vishnudas
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
| | - Niven R Narain
- Berg, LLC, 500 Old Connecticut Path, Bldg B (3rd Floor), Framingham, MA 01701 USA
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Wu WS, Zhu L, Patil S, Gokul K, Reilly S, Chan J, Tekumalla P, Vishnudas V, Kiebish MA, Sarangarajan R, Akmaev VR, Kellogg MD, Narain NR. Human CCDC47 sandwich immunoassay development with electrochemiluminescence technology. J Immunol Methods 2017; 452:12-19. [PMID: 28974366 DOI: 10.1016/j.jim.2017.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 09/28/2017] [Accepted: 09/29/2017] [Indexed: 11/26/2022]
Abstract
Coiled-Coil Domain Containing 47 (CCDC47) is an endoplasmic reticulum (ER) transmembrane protein involved in calcium signaling through utilization of its calcium binding-acidic luminal domain. CCDC47 also interacts with ERAD (endoplasmic reticulum-associated degradation) complex and is involved in ER stress relief. In this report, we developed human CCDC47 monoclonal antibodies and a sandwich immunoassay for CCDC47 measurement in biological matrices. Specificity of developed antibodies were confirmed by immunoblot and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of immunoprecipitated cell lysates. To achieve high analytical sensitivity, traditional colorimetric enzyme-linked immunosorbent assay (ELISA) and electrochemiluminescence (ECL) technology were compared, and 3 logs of increased sensitivity was observed with the use of ECL. A CCDC47 sandwich ECL assay was subsequently developed and performances evaluated for calibration curves, precision and accuracy, as well as selectivity and interferences for sample measurement. Sample stability was also characterized for freeze/thaw cycles and short/long term storage conditions.
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Affiliation(s)
- Wenfang S Wu
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA; Department of Pathology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA.
| | - Liang Zhu
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
| | - Saurabh Patil
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
| | - Karthiga Gokul
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
| | - Sean Reilly
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
| | - Joyce Chan
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
| | | | - Vivek Vishnudas
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
| | | | | | | | - Mark D Kellogg
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA; Department of Pathology, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Niven R Narain
- BERG, LLC, 500 Old Connecticut Path, Framingham, MA 01701, USA
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14
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Van B, Nishi M, Komazaki S, Ichimura A, Kakizawa S, Nakanaga K, Aoki J, Park KH, Ma J, Ueyama T, Ogata T, Maruyama N, Takeshima H. Mitsugumin 56 (hedgehog acyltransferase-like) is a sarcoplasmic reticulum-resident protein essential for postnatal muscle maturation. FEBS Lett 2015; 589:1095-104. [DOI: 10.1016/j.febslet.2015.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 03/24/2015] [Accepted: 03/26/2015] [Indexed: 02/02/2023]
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15
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Yamamoto S, Yamazaki T, Komazaki S, Yamashita T, Osaki M, Matsubayashi M, Kidoya H, Takakura N, Yamazaki D, Kakizawa S. Contribution of calumin to embryogenesis through participation in the endoplasmic reticulum-associated degradation activity. Dev Biol 2014; 393:33-43. [DOI: 10.1016/j.ydbio.2014.06.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Revised: 06/27/2014] [Accepted: 06/28/2014] [Indexed: 11/29/2022]
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16
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TRIC channels supporting efficient Ca2+ release from intracellular stores. Pflugers Arch 2012; 465:187-95. [DOI: 10.1007/s00424-012-1197-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 11/30/2012] [Accepted: 11/30/2012] [Indexed: 12/22/2022]
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17
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Konno M, Shirakawa H, Miyake T, Sakimoto S, Nakagawa T, Kaneko S. Calumin, a Ca²⁺-binding protein on the endoplasmic reticulum, alters the ion permeability of Ca²⁺ release-activated Ca²⁺ (CRAC) channels. Biochem Biophys Res Commun 2011; 417:784-9. [PMID: 22197811 DOI: 10.1016/j.bbrc.2011.12.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Accepted: 12/08/2011] [Indexed: 12/30/2022]
Abstract
Store-operated channels (SOC) are Ca(2+)-permeable channels that are activated by IP(3)-receptor-mediated Ca(2+) depletion of the endoplasmic reticulum (ER). Recent studies identify a membrane pore subunits, Orai1 and a Ca(2+) sensor on ER, STIM1 as components of Ca(2+) release-activated Ca(2+) (CRAC) channels, which are well-characterized SOCs. On the other hand, proteins that act as modulators of SOC activity remain to be identified. Calumin is a Ca(2+)-binding protein that resides on the ER and functional experiments using calumin-null mice demonstrate that it is involved in SOC function, although its role is unknown. This study used electrophysiological analysis to explore whether calumin modulates CRAC channel activity. CRAC channel currents were absent in HEK293 cells co-expressing calumin with the CRAC channel components, Orai1 or STIM1. Meanwhile, HEK cells that co-expressed calumin with CRAC channels exhibited larger currents with slower inactivation than cells expressing CRAC channels alone. The current-voltage relationship showed an inwardly rectifying current, but a negative shift in the reversal potential of greater than 60mV was observed in HEK cells co-expressing calumin with CRAC channels. In addition, the permeability coefficient ratio of Ca(2+) over monovalent cations was much lower than that of cells expressing CRAC channels alone. Replacement of Na(+) with N-methyl-d-glucamine(+) in the external solution noticeably diminished the CRAC current in HEK cells co-expressing calumin and CRAC channels. In a Cs(+)-based external solution, CRAC current was not observed in either cell-type. In addition, Ca(2+) imaging analysis revealed that co-transfection of calumin reduced extracellular Ca(2+) influx via CRAC channels. Further, calumin was shown to be directly associated with CRAC channels. These results reveal a novel mechanism for the regulation of CRAC channels by calumin.
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Affiliation(s)
- Masakazu Konno
- Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
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Venturi E, Mio K, Nishi M, Ogura T, Moriya T, Pitt SJ, Okuda K, Kakizawa S, Sitsapesan R, Sato C, Takeshima H. Mitsugumin 23 forms a massive bowl-shaped assembly and cation-conducting channel. Biochemistry 2011; 50:2623-32. [PMID: 21381722 PMCID: PMC3065873 DOI: 10.1021/bi1019447] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mitsugumin 23 (MG23) is a 23 kDa transmembrane protein localized to the sarcoplasmic/endoplasmic reticulum and nuclear membranes in a wide variety of cells. Although the characteristics imply the participation in a fundamental function in intracellular membrane systems, the physiological role of MG23 is unknown. Here we report the biochemical and biophysical characterization of MG23. Hydropathicity profile and limited proteolytic analysis proposed three transmembrane segments in the MG23 primary structure. Chemical cross-linking analysis suggested a homo-oligomeric assembly of MG23. Ultrastructural observations detected a large symmetrical particle as the predominant component and a small asymmetric assembly as the second major component in highly purified MG23 preparations. Single-particle three-dimensional reconstruction revealed that MG23 forms a large bowl-shaped complex equipped with a putative central pore, which is considered an assembly of the small asymmetric subunit. After reconstitution into planar phospholipid bilayers, purified MG23 behaved as a voltage-dependent, cation-conducting channel, permeable to both K(+) and Ca(2+). A feature of MG23 gating was that multiple channels always appeared to be gating together in the bilayer. Our observations suggest that the bowl-shaped MG23 can transiently assemble and disassemble. These building transitions may underlie the unusual channel gating behavior of MG23 and allow rapid cationic flux across intracellular membrane systems.
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Affiliation(s)
- Elisa Venturi
- School of Physiology and Pharmacology, Bristol Heart Institute and Centre for Nanoscience and Quantum Information, University of Bristol, Bristol, United Kingdom
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Yamazaki T, Sasaki N, Nishi M, Takeshima H. Facilitation of DNA damage-induced apoptosis by endoplasmic reticulum protein mitsugumin23. Biochem Biophys Res Commun 2010; 392:196-200. [PMID: 20060811 DOI: 10.1016/j.bbrc.2010.01.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2010] [Accepted: 01/05/2010] [Indexed: 01/21/2023]
Abstract
The endoplasmic reticulum (ER) emanates context-dependent signals, thereby mediating cellular response to a variety of stresses. However, the underlying molecular mechanisms have been enigmatic. To better understand the signaling capacity of the ER, we focused on roles played by mitsugumin23 (MG23), a protein residing predominantly in this organelle. Overexpression of MG23 in human embryonic kidney 293T cells specifically enhanced apoptosis triggered by etoposide, a DNA-damaging anti-cancer drug. Conversely, genetic deletion of MG23 reduced susceptibility of thymocytes to DNA damage-induced apoptosis, which was demonstrated by whole-body irradiation experiments. In this setting, induction of the tumor-suppressor gene p53 was attenuated in MG23-knockout thymocytes as compared with their wild-type counterparts, consistent with the elevated radioresistance. It is therefore suggested that MG23 is an essential component of ER-generated lethal signals provoked upon DNA damage, specifying cell fate under pathophysiological conditions.
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Affiliation(s)
- Tetsuo Yamazaki
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
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Abstract
Malignant hyperthermia (MH) is a pharmacogenetic disorder triggered by volatile anesthetics or depolarizing muscle relaxants in predisposed individuals. Exercise or stress-induced MH episodes, in the absence of any obvious pharmacological trigger, have been reported, but these are rare. A considerable effort has taken place over the last two decades to identify mutations associated with MH and characterize their functional effects. A number of different, but complementary systems, have been developed and implemented to this end. The results of such studies have identified commonalities in functional affects of mutations, and also uncovered unexpected complexities in both the structure and function of the skeletal muscle calcium-release channel. The following review is an attempt to provide a summary of the background to current MH research, and highlight some recent advances in our knowledge of the molecular basis of the phenotypic expression of this disorder.
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Affiliation(s)
- Kathryn M Stowell
- Institute of Molecular Biosciences, Massey University, Palmerston North, New Zealand.
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Weisleder N, Takeshima H, Ma J. Immuno-proteomic approach to excitation--contraction coupling in skeletal and cardiac muscle: molecular insights revealed by the mitsugumins. Cell Calcium 2008; 43:1-8. [PMID: 18061662 PMCID: PMC3059838 DOI: 10.1016/j.ceca.2007.10.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 10/17/2007] [Accepted: 10/19/2007] [Indexed: 12/20/2022]
Abstract
A comprehensive understanding of excitation-contraction (E-C) coupling in skeletal and cardiac muscle requires that all the major components of the Ca(2+) release machinery be resolved. We utilized a unique immuno-proteomic approach to generate a monoclonal antibody library that targets proteins localized to the skeletal muscle triad junction, which provides a structural context to allow efficient E-C coupling. Screening of this library has identified several mitsugumins (MG); proteins that can be localized to the triad junction in mammalian skeletal muscle. Many of these proteins, including MG29 and junctophilin, are important components in maintaining the structural integrity of the triad junction. Other triad proteins, such as calumin, play a more direct role in regulation of muscle Ca(2+) homeostasis. We have recently identified a family of trimeric intracellular cation-selective (TRIC) channels that allow for K(+) movement into the endoplasmic or sarcoplasmic reticulum to counter a portion of the transient negative charge produced by Ca(2+) release into the cytosol. Further study of TRIC channel function and other novel mitsugumins will increase our understanding of E-C coupling and Ca(2+) homoeostasis in muscle physiology and pathophysiology.
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Affiliation(s)
- Noah Weisleder
- Department of Physiology and Biophysics, UMDNJ-Robert Wood Johnson Medical School, NJ 08854, USA
| | - Hiroshi Takeshima
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Jianjie Ma
- Department of Physiology and Biophysics, UMDNJ-Robert Wood Johnson Medical School, NJ 08854, USA
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Yamazaki T, Sasaki N, Nishi M, Yamazaki D, Ikeda A, Okuno Y, Komazaki S, Takeshima H. Augmentation of drug-induced cell death by ER protein BRI3BP. Biochem Biophys Res Commun 2007; 362:971-5. [PMID: 17765869 DOI: 10.1016/j.bbrc.2007.08.082] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2007] [Accepted: 08/15/2007] [Indexed: 11/29/2022]
Abstract
To determine the contribution of the endoplasmic reticulum (ER) to cell fate decision, we focused on BRI3-binding protein (BRI3BP) residing in this organelle. BRI3BP, when overexpressed, augmented the apoptosis of human embryonic kidney 293T cells challenged with drugs including the anti-cancer agent etoposide. In contrast, the knockdown of BRI3BP reduced the drug-triggered apoptosis. BRI3BP overexpression enhanced both mitochondrial cytochrome c release and caspase-3 activity in etoposide-treated cells. In response to etoposide, the ER reorganized into irregularly shaped lamellae in mock-transfected cells, whereas in BRI3BP-overexpressing cells, such reorganization was not observed. These observations suggest that BRI3BP is involved in the structural dynamics of the ER and affects mitochondrial viability. Taken together, BRI3BP, widely expressed in animal cell types, seems to possess a pro-apoptotic property and can potentiate drug-induced apoptosis.
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Affiliation(s)
- Tetsuo Yamazaki
- The 21st Century Center of Excellence Program, Tohoku University Graduate School of Medicine, Sendai 980-8575, Japan.
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