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Goyal RK, Rattan S. Role of mechanoregulation in mast cell-mediated immune inflammation of the smooth muscle in the pathophysiology of esophageal motility disorders. Am J Physiol Gastrointest Liver Physiol 2024; 326:G398-G410. [PMID: 38290993 PMCID: PMC11213482 DOI: 10.1152/ajpgi.00258.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/15/2024] [Accepted: 01/29/2024] [Indexed: 02/01/2024]
Abstract
Major esophageal disorders involve obstructive transport of bolus to the stomach, causing symptoms of dysphagia and impaired clearing of the refluxed gastric contents. These may occur due to mechanical constriction of the esophageal lumen or loss of relaxation associated with deglutitive inhibition, as in achalasia-like disorders. Recently, immune inflammation has been identified as an important cause of esophageal strictures and the loss of inhibitory neurotransmission. These disorders are also associated with smooth muscle hypertrophy and hypercontractility, whose cause is unknown. This review investigated immune inflammation in the causation of smooth muscle changes in obstructive esophageal bolus transport. Findings suggest that smooth muscle hypertrophy occurs above the obstruction and is due to mechanical stress on the smooth muscles. The mechanostressed smooth muscles release cytokines and other molecules that may recruit and microlocalize mast cells to smooth muscle bundles, so that their products may have a close bidirectional effect on each other. Acting in a paracrine fashion, the inflammatory cytokines induce genetic and epigenetic changes in the smooth muscles, leading to smooth muscle hypercontractility, hypertrophy, and impaired relaxation. These changes may worsen difficulty in the esophageal transport. Immune processes differ in the first phase of obstructive bolus transport, and the second phase of muscle hypertrophy and hypercontractility. Moreover, changes in the type of mechanical stress may change immune response and effect on smooth muscles. Understanding immune signaling in causes of obstructive bolus transport, type of mechanical stress, and associated smooth muscle changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.NEW & NOTEWORTHY Esophageal disorders such as esophageal stricture or achalasia, and diffuse esophageal spasm are associated with smooth muscle hypertrophy and hypercontractility, above the obstruction, yet the cause of such changes is unknown. This review suggests that smooth muscle obstructive disorders may cause mechanical stress on smooth muscle, which then secretes chemicals that recruit, microlocalize, and activate mast cells to initiate immune inflammation, producing functional and structural changes in smooth muscles. Understanding the immune signaling in these changes may help pathophysiology-based prevention and targeted treatment of esophageal motility disorders.
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Affiliation(s)
- Raj K Goyal
- Division of Gastroenterology, Department of Medicine, Veterans Affairs Boston Healthcare System, West Roxbury, Massachusetts, United States
- Division of Gastroenterology, Hepatology, and Endoscopy, Department of Medicine, Beth Israel Deaconess Medical Center, and Harvard Medical School, Boston, Massachusetts, United States
| | - Satish Rattan
- Department of Medicine, Division of Gastroenterology and Hepatology, Sidney Kummel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, United States
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Chen S, Xing X, Hou X, Zhuang Q, Tan N, Cui Y, Wang J, Zhang M, Hu S, Xiao Y. The molecular pathogenesis of achalasia: a paired lower esophageal sphincter muscle and serum 4D label-free proteomic study. Gastroenterol Rep (Oxf) 2023; 11:goad031. [PMID: 37324545 PMCID: PMC10260389 DOI: 10.1093/gastro/goad031] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 04/11/2023] [Accepted: 05/03/2023] [Indexed: 06/17/2023] Open
Abstract
Background Achalasia is a primary esophageal motility disorder with potential molecular pathogenesis remaining uncertain. This study aimed to identify the differentially expressed proteins and potential pathways among achalasia subtypes and controls to further reveal the molecular pathogenesis of achalasia. Methods Paired lower esophageal sphincter (LES) muscle and serum samples from 24 achalasia patients were collected. We also collected 10 normal serum samples from healthy controls and 10 normal LES muscle samples from esophageal cancer patients. The 4D label-free proteomic analysis was performed to identify the potential proteins and pathways involved in achalasia. Results Analysis of Similarities showed distinct proteomic patterns of serum and muscle samples between achalasia patients and controls (both P < 0.05). Functional enrichment analysis suggested that these differentially expressed proteins were immunity-, infection-, inflammation-, and neurodegeneration-associated. The mfuzz analysis in LES specimens showed that proteins involved in the extracellular matrix-receptor interaction increased sequentially between the control group, type III, type II, and type I achalasia. Only 26 proteins altered in the same directions in serum and muscle samples. Conclusions This first 4D label-free proteomic study of achalasia indicated that there were specific protein alterations in both the serum and muscle of achalasia, involving immunity, inflammation, infection, and neurodegeneration pathways. Distinct protein clusters between types I, II, and III revealed the potential molecular pathways associated with different disease stages. Analysis of proteins changed in both muscle and serum samples highlighted the importance of further studies on LES muscle and revealed potential autoantibodies.
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Affiliation(s)
| | | | - Xun Hou
- Gastrointestinal Surgery Center, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Qianjun Zhuang
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Niandi Tan
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Yi Cui
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Jinhui Wang
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Mengyu Zhang
- Department of Gastroenterology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Shixian Hu
- Institute of Precision Medicine, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
| | - Yinglian Xiao
- Corresponding author. Department of Gastroenterology, The First Affiliated Hospital, Sun Yat-sen University, No. 58 Zhongshan Road 2, Guangzhou, Guangdong 510080, P. R. China. Tel: +86-13560172116;
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Prüschenk S, Majer M, Schlossmann J. Novel Functional Features of cGMP Substrate Proteins IRAG1 and IRAG2. Int J Mol Sci 2023; 24:9837. [PMID: 37372987 DOI: 10.3390/ijms24129837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/01/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
The inositol triphosphate-associated proteins IRAG1 and IRAG2 are cGMP kinase substrate proteins that regulate intracellular Ca2+. Previously, IRAG1 was discovered as a 125 kDa membrane protein at the endoplasmic reticulum, which is associated with the intracellular Ca2+ channel IP3R-I and the PKGIβ and inhibits IP3R-I upon PKGIβ-mediated phosphorylation. IRAG2 is a 75 kDa membrane protein homolog of IRAG1 and was recently also determined as a PKGI substrate. Several (patho-)physiological functions of IRAG1 and IRAG2 were meanwhile elucidated in a variety of human and murine tissues, e.g., of IRAG1 in various smooth muscles, heart, platelets, and other blood cells, of IRAG2 in the pancreas, heart, platelets, and taste cells. Hence, lack of IRAG1 or IRAG2 leads to diverse phenotypes in these organs, e.g., smooth muscle and platelet disorders or secretory deficiency, respectively. This review aims to highlight the recent research regarding these two regulatory proteins to envision their molecular and (patho-)physiological tasks and to unravel their functional interplay as possible (patho-)physiological counterparts.
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Affiliation(s)
- Sally Prüschenk
- Department of Pharmacology and Toxicology, Institute of Pharmacy, University of Regensburg, 93040 Regensburg, Germany
| | - Michael Majer
- Department of Pharmacology and Toxicology, Institute of Pharmacy, University of Regensburg, 93040 Regensburg, Germany
| | - Jens Schlossmann
- Department of Pharmacology and Toxicology, Institute of Pharmacy, University of Regensburg, 93040 Regensburg, Germany
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Micale L, Fusco C, Nardella G, Palmieri O, Latiano T, Gioffreda D, Tavano F, Panza A, Merla A, Biscaglia G, Gentile M, Cuttitta A, Castori M, Perri F, Latiano A. Downexpression of miR-200c-3p Contributes to Achalasia Disease by Targeting the PRKG1 Gene. Int J Mol Sci 2022; 24:ijms24010668. [PMID: 36614110 PMCID: PMC9820813 DOI: 10.3390/ijms24010668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/20/2022] [Accepted: 12/23/2022] [Indexed: 01/03/2023] Open
Abstract
Achalasia is an esophageal smooth muscle motility disorder with unknown pathogenesis. Taking into account our previous results on the downexpression of miR-200c-3p in tissues of patients with achalasia correlated with an increased expression of PRKG1, SULF1, and SYDE1 genes, our aim was to explore the unknown biological interaction between these genes and human miR-200c-3p and if this relation could unravel their functional role in the etiology of achalasia. To search for putative miR-200c-3p binding sites in the 3'-UTR of PRKG1, SULF1 and SYDE1, a bioinformatics tool was used. To test whether PRKG1, SULF1, and SYDE1 are targeted by miR-200c-3p, a dual-luciferase reporter assay and quantitative PCR on HEK293 and fibroblast cell lines were performed. To explore the biological correlation between PRKG1 and miR-200c-3p, an immunoblot analysis was carried out. The overexpression of miR-200c-3p reduced the luciferase activity in cells transfected with a luciferase reporter containing a fragment of the 3'-UTR regions of PRKG1, SULF1, and SYDE1 which included the miR-200c-3p seed sequence. The deletion of the miR-200c-3p seed sequence from the 3'-UTR fragments abrogated this reduction. A negative correlation between miR-200c-3p and PRKG1, SULF1, and SYDE1 expression levels was observed. Finally, a reduction of the endogenous level of PRKG1 in cells overexpressing miR-200c-3p was detected. Our study provides, for the first time, functional evidence about the PRKG1 gene as a direct target and SULF1 and SYDE1 as potential indirect substrates of miR-200c-3p and suggests the involvement of NO/cGMP/PKG signaling in the pathogenesis of achalasia.
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Affiliation(s)
- Lucia Micale
- Division of Medical Genetics, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Carmela Fusco
- Division of Medical Genetics, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Grazia Nardella
- Division of Medical Genetics, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Orazio Palmieri
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Tiziana Latiano
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Domenica Gioffreda
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Francesca Tavano
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Anna Panza
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Antonio Merla
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Giuseppe Biscaglia
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Marco Gentile
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Antonello Cuttitta
- Unit of Thoracic Surgery, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Marco Castori
- Division of Medical Genetics, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Francesco Perri
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
| | - Anna Latiano
- Division of Gastroenterology, Fondazione IRCCS Casa Sollievo della Sofferenza, 71013 San Giovanni Rotondo, Italy
- Correspondence: ; Tel.: +39-0882-416281
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Petrizzelli F, Biagini T, Bianco SD, Liorni N, Napoli A, Castellana S, Mazza T. Connecting the dots: A practical evaluation of web-tools for describing protein dynamics as networks. FRONTIERS IN BIOINFORMATICS 2022; 2:1045368. [PMID: 36438625 PMCID: PMC9689706 DOI: 10.3389/fbinf.2022.1045368] [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: 09/15/2022] [Accepted: 10/05/2022] [Indexed: 01/25/2023] Open
Abstract
Protein Structure Networks (PSNs) are a well-known mathematical model for estimation and analysis of the three-dimensional protein structure. Investigating the topological architecture of PSNs may help identify the crucial amino acid residues for protein stability and protein-protein interactions, as well as deduce any possible mutational effects. But because proteins go through conformational changes to give rise to essential biological functions, this has to be done dynamically over time. The most effective method to describe protein dynamics is molecular dynamics simulation, with the most popular software programs for manipulating simulations to infer interaction networks being RING, MD-TASK, and NAPS. Here, we compare the computational approaches used by these three tools-all of which are accessible as web servers-to understand the pathogenicity of missense mutations and talk about their potential applications as well as their advantages and disadvantages.
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Affiliation(s)
- Francesco Petrizzelli
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Tommaso Biagini
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Salvatore Daniele Bianco
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy,Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Niccolò Liorni
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy,Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Alessandro Napoli
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Stefano Castellana
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Tommaso Mazza
- Bioinformatics Laboratory, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy,*Correspondence: Tommaso Mazza,
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GHOLIPOUR M, MIKAELI J, MOWLA SJ, BAKHTIARIZADEH MR, SAGHAEIAN JAZI M, JAVID N, FAZLOLLAHI N, KHOSHNIA M, BEHNAMPOUR N, MORADI A. Identification of differentially expressed microRNAs in primary esophageal achalasia by next-generation sequencing. Turk J Biol 2021; 45:262-274. [PMID: 34377051 PMCID: PMC8313935 DOI: 10.3906/biy-2101-61] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/08/2021] [Indexed: 11/29/2022] Open
Abstract
Molecular knowledge regarding the primary esophageal achalasia is essential for the early diagnosis and treatment of this neurodegenerative motility disorder. Therefore, there is a need to find the main microRNAs (miRNAs) contributing to the mechanisms of achalasia. This study was conducted to determine some patterns of deregulated miRNAs in achalasia. This case-control study was performed on 52 patients with achalasia and 50 nonachalasia controls. The miRNA expression profiling was conducted on the esophageal tissue samples using the next-generation sequencing (NGS). Differential expression of miRNAs was analyzed by the edgeR software. The selected dysregulated miRNAs were additionally confirmed using the quantitative reverse transcription polymerase chain reaction (qRT-PCR). Fifteen miRNAs were identified that were significantly altered in the tissues of the patients with achalasia. Among them, three miRNAs including miR-133a-5p, miR-143-3p, and miR-6507-5p were upregulated. Also, six miRNAs including miR-215-5p, miR-216a-5p, miR-216b-5p, miR-217, miR-7641 and miR-194-5p were downregulated significantly. The predicted targets for the dysregulated miRNAs showed significant disease-associated pathways like neuronal cell apoptosis, neuromuscular balance, nerve growth factor signaling, and immune response regulation. Further analysis using qRT-PCR showed significant down-regulation of hsa-miR-217 (p-value = 0.004) in achalasia tissue. Our results may serve as a basis for more future functional studies to investigate the role of candidate miRNAs in the etiology of achalasia and their application in the diagnosis and probably treatment of the disease.
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Affiliation(s)
- Mahin GHOLIPOUR
- Golestan Research Center of Gastroenterology and Hepatology, Golestan University of Medical Sciences, GorganIran
| | - Javad MIKAELI
- Autoimmune and Motility Disorders Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, TehranIran
| | - Seyed Javad MOWLA
- Department of Genetics, Faculty of Biological Sciences, Tarbiat Modares University, TehranIran
| | | | - Marie SAGHAEIAN JAZI
- Metabolic Disorders Research Center, Golestan University of Medical Sciences, GorganIran
| | - Naeme JAVID
- Department of Microbiology, Faculty of Medicine, Golestan University of Medical Sciences, GorganIran
| | - Narges FAZLOLLAHI
- Autoimmune and Motility Disorders Research Center, Digestive Diseases Research Institute, Tehran University of Medical Sciences, TehranIran
| | - Masoud KHOSHNIA
- Golestan Research Center of Gastroenterology and Hepatology, Golestan University of Medical Sciences, GorganIran
| | - Naser BEHNAMPOUR
- Department of Biostatistics, Faculty of Health, Golestan University of Medical Sciences, GorganIran
| | - Abdolvahab MORADI
- Golestan Research Center of Gastroenterology and Hepatology, Golestan University of Medical Sciences, GorganIran
- Department of Microbiology, Faculty of Medicine, Golestan University of Medical Sciences, GorganIran
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Loss of PKGIβ/IRAG1 Signaling Causes Anemia-Associated Splenomegaly. Int J Mol Sci 2021; 22:ijms22115458. [PMID: 34064290 PMCID: PMC8196906 DOI: 10.3390/ijms22115458] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 01/24/2023] Open
Abstract
Inositol 1,4,5-triphosphate receptor-associated cGMP kinase substrate 1 (IRAG1) is a substrate protein of the NO/cGMP-signaling pathway and forms a ternary complex with the cGMP-dependent protein kinase Iβ (PKGIβ) and the inositol triphosphate receptor I (IP3R-I). Functional studies about IRAG1 exhibited that IRAG1 is specifically phosphorylated by the PKGIβ, regulating cGMP-mediated IP3-dependent Ca2+-release. IRAG1 is widely distributed in murine tissues, e.g., in large amounts in smooth muscle-containing tissues and platelets, but also in lower amounts, e.g., in the spleen. The NO/cGMP/PKGI signaling pathway is important in several organ systems. A loss of PKGI causes gastrointestinal disorders, anemia and splenomegaly. Due to the similar tissue distribution of the PKGIβ to IRAG1, we investigated the pathophysiological functions of IRAG1 in this context. Global IRAG1-KO mice developed gastrointestinal bleeding, anemia-associated splenomegaly and iron deficiency. Additionally, Irag1-deficiency altered the protein levels of some cGMP/PKGI signaling proteins—particularly a strong decrease in the PKGIβ—in the colon, spleen and stomach but did not change mRNA-expression of the corresponding genes. The present work showed that a loss of IRAG1 and the PKGIβ/IRAG1 signaling has a crucial function in the development of gastrointestinal disorders and anemia-associated splenomegaly. Furthermore, global Irag1-deficient mice are possible in vivo model to investigate PKGIβ protein functions.
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Koehler K, Hmida D, Schlossmann J, Landgraf D, Reisch N, Schuelke M, Huebner A. Homozygous mutation in murine retrovirus integration site 1 gene associated with a non-syndromic form of isolated familial achalasia. Neurogastroenterol Motil 2020; 32:e13923. [PMID: 32573102 DOI: 10.1111/nmo.13923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/18/2020] [Accepted: 05/25/2020] [Indexed: 01/23/2023]
Abstract
BACKGROUND Achalasia is a condition characterized by impaired function of esophageal motility and incomplete relaxation of the lower esophagus sphincter, causing dysphagia and regurgitation. Rare cases of early-onset achalasia appear often in combination with further symptoms in a syndromic form as an inherited disease. METHODS Whole genome sequencing was used to investigate the genetic basis of isolated achalasia in a family of Tunisian origin. We analyzed the function of the affected protein with immunofluorescence and affinity chromatography study. KEY RESULTS A homozygous nonsense mutation was detected in murine retrovirus integration site 1 (MRVI1) gene (Human Genome Organisation Gene Nomenclature Committee (HGNC) approved gene symbol: IRAG1) encoding the inositol 1,4,5-trisphosphate receptor 1 (IP3 R1)-associated cyclic guanosine monophosphate (cGMP) kinase substrate (IRAG). Sanger sequencing confirmed co-segregation of the mutation with the disease. Sequencing of the entire MRVI1 gene in 35 additional patients with a syndromic form of achalasia did not uncover further cases with MRVI1 mutations. Immunofluorescence analysis of transfected COS7 cells revealed GFP-IRAG with the truncating mutation p.Arg112* (transcript variant 1) or p.Arg121* (transcript variant 2) to be mislocalized in the cytoplasm and the nucleus. Co-transfection with cGMP-dependent protein kinase 1 isoform β (cGK1β) depicted a partial mislocalization of cGK1β due to mislocalized truncated IRAG. Isolation of protein complexes revealed that the truncation of this protein causes the loss of the interaction domain of IRAG with cGK1β. CONCLUSIONS & INFERENCES In individuals with an early onset of achalasia without further accompanying symptoms, MRVI1 mutations should be considered as the disease-causing defect.
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Affiliation(s)
- Katrin Koehler
- Medizinische Fakultät Carl Gustav Carus, Children's Hospital, Technische Universität Dresden, Dresden, Germany
| | - Dorra Hmida
- Department of Medical Genetics, Anatomy and Cytology, Farhat Hached Hospital, Sousse, Tunisia
| | - Jens Schlossmann
- Department of Pharmacology and Toxicology, Institute of Pharmacy, University of Regensburg, Regensburg, Germany
| | - Dana Landgraf
- Medizinische Fakultät Carl Gustav Carus, Children's Hospital, Technische Universität Dresden, Dresden, Germany
| | - Nicole Reisch
- Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Markus Schuelke
- Department of Neuropediatrics and NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Angela Huebner
- Medizinische Fakultät Carl Gustav Carus, Children's Hospital, Technische Universität Dresden, Dresden, Germany
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