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Shinozuka T, Kanda M, Sato Y, Shimizu D, Tanaka C, Umeda S, Inokawa Y, Hattori N, Hayashi M, Nakayama G, Kodera Y. Increased STX3 transcript and protein levels were associated with poor prognosis in two independent cohorts of esophageal squamous cell carcinoma patients. Cancer Med 2023; 12:22185-22195. [PMID: 38014487 PMCID: PMC10757105 DOI: 10.1002/cam4.6770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 11/07/2023] [Accepted: 11/17/2023] [Indexed: 11/29/2023] Open
Abstract
BACKGROUND Some conventional prognostic biomarkers for esophageal squamous cell carcinoma (ESCC) have the disadvantage that they have only been investigated at the level of either mRNA or protein levels or only in individual cohorts. Associations between Syntaxin 3 (STX3) expression and malignancy have been reported in several tumor types but not in ESCC. Here, we investigated the levels of both STX3 mRNA and protein, and its prognostic potential in two independent cohorts of patients with ESCC. METHODS STX3 mRNA levels were examined in surgical specimens by quantitative PCR in a cohort that included 176 ESCC patients. STX3 protein levels were investigated in surgically resected ESCC tissues by immunohistochemistry using tissue microarrays in a different cohort of 177 ESCC patients. Correlations were analyzed between the expression of STX3 mRNA and protein with clinicopathological factors and long-term prognosis. RESULTS Quantitative PCR indicated a significant association between high level of STX3 mRNA expression and lymph node involvement, pathological stage, and poor overall survival. The multivariate analysis demonstrated that high STX3 mRNA expression was independently associated with poor overall survival outcomes. Immunohistochemistry revealed that STX3 protein expression in ESCC tissues and high STX3 protein expression were also significantly correlated with unfavorable overall survival. CONCLUSIONS Overexpression of STX3 mRNA and protein may serve as potential prognostic biomarkers for ESCC patients.
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Affiliation(s)
- Takahiro Shinozuka
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Mitsuro Kanda
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Yusuke Sato
- Department of Thoracic SurgeryAkita University Graduate School of MedicineAkitaJapan
| | - Dai Shimizu
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Chie Tanaka
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Shinichi Umeda
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Yoshikuni Inokawa
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Norifumi Hattori
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Masamichi Hayashi
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Goro Nakayama
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
| | - Yasuhiro Kodera
- Department of Gastroenterological SurgeryNagoya University Graduate School of MedicineNagoyaJapan
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Kondo D, Suzuki R, Matsumura A, Meguri H, Tanaka M, Itakura M, Hirashima N. Methiothepin downregulates SNAP-23 and inhibits degranulation of rat basophilic leukemia cells and mouse bone marrow-derived mast cells. Eur J Immunol 2023; 53:e2250360. [PMID: 37736882 DOI: 10.1002/eji.202250360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 08/19/2023] [Accepted: 09/19/2023] [Indexed: 09/23/2023]
Abstract
In the present study, we found that methiothepin (a nonselective 5-hydroxytryptamine [5-HT] receptor antagonist) inhibited antigen-induced degranulation in rat basophilic leukemia cells and mouse bone marrow-derived mast cells. Although antigen stimulation induces release of histamine and serotonin (5-HT) by exocytosis and mast cells express several types of 5-HT receptor, the detailed role of these receptors remains unclear. Here, pretreatment of cells with methiothepin attenuated increased intracellular Ca2+ concentration, phosphorylated critical upstream signaling components (Src family tyrosine kinases, Syk, and PLCγ1), and suppressed TNF-α secretion via inhibition of Akt (a Ser/Thr kinase activated by PI3K)and ERK phosphorylation. Furthermore, it inhibited PMA/ionomycin-induced degranulation; this finding suggested that methiothepin affected downstream signaling. IκB kinase β phosphorylates synaptosomal associated protein 23, which regulates the fusion events of the secretory granule/plasma membrane after mast cell activation, resulting in degranulation. We showed that methiothepin blocked PMA/ionomycin-induced phosphorylation of synaptosomal associated protein 23 by inhibiting its interaction with IκB kinase β. Together with the results of selective 5-HT antagonists, it is suggested that methiothepin inhibits mast cell degranulation by downregulating upstream signaling pathways and exocytotic fusion machinery through mainly 5-HT1A receptor. Our findings provide that 5-HT antagonists may be used to relieve allergic reactions.
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Affiliation(s)
- Daisuke Kondo
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Ruriko Suzuki
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Ayako Matsumura
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Hitomi Meguri
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Masahiko Tanaka
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
| | - Makoto Itakura
- Department of Biochemistry, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
| | - Naohide Hirashima
- Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, Japan
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3
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Plitt MH, Kaganovsky K, Südhof TC, Giocomo LM. Hippocampal place code plasticity in CA1 requires postsynaptic membrane fusion. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.20.567978. [PMID: 38045362 PMCID: PMC10690209 DOI: 10.1101/2023.11.20.567978] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Rapid delivery of glutamate receptors to the postsynaptic membrane via vesicle fusion is a central component of synaptic plasticity. However, it is unknown how this process supports specific neural computations during behavior. To bridge this gap, we combined conditional genetic deletion of a component of the postsynaptic membrane fusion machinery, Syntaxin3 (Stx3), in hippocampal CA1 neurons of mice with population in vivo calcium imaging. This approach revealed that Stx3 is necessary for forming the neural dynamics that support novelty processing, spatial reward memory and offline memory consolidation. In contrast, CA1 Stx3 was dispensable for maintaining aspects of the neural code that exist presynaptic to CA1 such as representations of context and space. Thus, manipulating postsynaptic membrane fusion identified computations that specifically require synaptic restructuring via membrane trafficking in CA1 and distinguished them from neural representation that could be inherited from upstream brain regions or learned through other mechanisms.
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4
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Snyder K, Gorse K, Kochanek PM, Jackson TC. Neuronal RBM5 modulates cell signaling responses to traumatic and hypoxic-ischemic injury in a sex-dependent manner. Cell Death Discov 2023; 9:379. [PMID: 37848418 PMCID: PMC10582027 DOI: 10.1038/s41420-023-01677-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 09/22/2023] [Accepted: 10/03/2023] [Indexed: 10/19/2023] Open
Abstract
It is not clear if inhibiting the pro-death gene RNA binding motif 5 (RBM5) is neuroprotective in isolated primary neurons or if it regulates cell survival in a sex-dependent manner. Here we established sex-dichotomized primary cortical neuron cultures from transgenic mice harboring a floxed RBM5 gene-trap. Lentivirus-mediated expression of CRE was used to silence RBM5 expression. Male and female neurons were maintained in next-generation Neurobasal-Plus media and subjected to a mechanical stretch-injury (to model traumatic brain injury) or oxygen-glucose deprivation/OGD (to model ischemia). RBM5 KO did not affect 24 h post-injury survival as determined by lactate dehydrogenase (LDH) release, in either paradigm. In contrast, female KO neurons had increased spectrin breakdown products post-insult (in both models). Furthermore, in OGD, RBM5 KO in male neurons exacerbated injury-induced downregulation of pro-survival AKT activation (pAKT473) but conversely led to pAKT473 sparing in female neurons. Moreover, global proteomics identified 19 differentially expressed (DE) proteins in OGD-injured male neurons, and 102 DE proteins in injured female neurons. Two novel RBM5-regulated proteins (PIGQ and EST1C) were identified in injured male KO neurons, and 8 novel proteins identified in injured female KO neurons (S35A5, DHTK1, STX3, IF3M, RN167, K1C14, DYHS, and MED13). In summary, RBM5 inhibition does not modify neuronal survival in primary mouse neurons in 2 clinically relevant models of excitotoxic insult, but RBM5 does regulate intracellular responses to injury in a sex-dependent manner.
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Affiliation(s)
- Kara Snyder
- University of South Florida, Morsani College of Medicine, USF Health Heart Institute, MDD 0630, 560 Channelside Dr, Tampa, FL, 33602, USA
- University of South Florida, Morsani College of Medicine, Department of Molecular Pharmacology & Physiology, 12901 Bruce B Downs Blvd, Tampa, FL, 33612, USA
| | - Kiersten Gorse
- University of South Florida, Morsani College of Medicine, USF Health Heart Institute, MDD 0630, 560 Channelside Dr, Tampa, FL, 33602, USA
- University of South Florida, Morsani College of Medicine, Department of Molecular Pharmacology & Physiology, 12901 Bruce B Downs Blvd, Tampa, FL, 33612, USA
| | - Patrick M Kochanek
- Safar Center for Resuscitation Research, UPMC Children's Hospital of Pittsburgh, Rangos Research Center - 6th floor, Pittsburgh, PA, 15224, USA
| | - Travis C Jackson
- University of South Florida, Morsani College of Medicine, USF Health Heart Institute, MDD 0630, 560 Channelside Dr, Tampa, FL, 33602, USA.
- University of South Florida, Morsani College of Medicine, Department of Molecular Pharmacology & Physiology, 12901 Bruce B Downs Blvd, Tampa, FL, 33612, USA.
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Nishad R, Betancourt-Solis M, Dey H, Heidelberger R, McNew JA. Regulation of Syntaxin3B-Mediated Membrane Fusion by T14, Munc18, and Complexin. Biomolecules 2023; 13:1463. [PMID: 37892145 PMCID: PMC10604575 DOI: 10.3390/biom13101463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/22/2023] [Accepted: 09/26/2023] [Indexed: 10/29/2023] Open
Abstract
Retinal neurons that form ribbon-style synapses operate over a wide dynamic range, continuously relaying visual information to their downstream targets. The remarkable signaling abilities of these neurons are supported by specialized presynaptic machinery, one component of which is syntaxin3B. Syntaxin3B is an essential t-SNARE protein of photoreceptors and bipolar cells that is required for neurotransmitter release. It has a light-regulated phosphorylation site in its N-terminal domain at T14 that has been proposed to modulate membrane fusion. However, a direct test of the latter has been lacking. Using a well-controlled in vitro fusion assay, we found that a phosphomimetic T14 syntaxin3B mutation leads to a small but significant enhancement of SNARE-mediated membrane fusion following the formation of the t-SNARE complex. While the addition of Munc18a had only a minimal effect on membrane fusion mediated by SNARE complexes containing wild-type syntaxin3B, a more significant enhancement was observed in the presence of Munc18a when the SNARE complexes contained a syntaxin3B T14 phosphomimetic mutant. Finally, we showed that the retinal-specific complexins (Cpx III and Cpx IV) inhibited membrane fusion mediated by syntaxin3B-containing SNARE complexes in a dose-dependent manner. Collectively, our results establish that membrane fusion mediated by syntaxin3B-containing SNARE complexes is regulated by the T14 residue of syntaxin3B, Munc18a, and Cpxs III and IV.
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Affiliation(s)
- Rajkishor Nishad
- Department of BioSciences, Rice University, 6500 Main Street, MS 601, Houston, TX 77005, USA;
| | - Miguel Betancourt-Solis
- Department of BioSciences, Rice University, 6500 Main Street, MS 601, Houston, TX 77005, USA;
- Lonza Biologics, 14905 Kirby Dr, Houston, TX 77047, USA
| | - Himani Dey
- Department of Neurobiology and Anatomy, McGovern Medical School, The University of Texas Health Science Center, Houston (UTHealth Houston), 6431 Fannin Street, Houston, TX 77030, USA;
| | - Ruth Heidelberger
- Department of Neurobiology and Anatomy, McGovern Medical School, The University of Texas Health Science Center, Houston (UTHealth Houston), 6431 Fannin Street, Houston, TX 77030, USA;
| | - James A. McNew
- Department of BioSciences, Rice University, 6500 Main Street, MS 601, Houston, TX 77005, USA;
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6
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Hayashi K, Nozaki S, Tokushima K, Tanaka F, Hirai Y. Role of syntaxin3 an apical polarity protein in poorly polarized keratinocytes: regulation of asymmetric barrier formations in the skin epidermis. Cell Tissue Res 2023; 393:523-535. [PMID: 37351635 DOI: 10.1007/s00441-023-03798-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 06/13/2023] [Indexed: 06/24/2023]
Abstract
The skin epidermis exhibits an asymmetric structure composed of multilayered keratinocytes and those in the outer layers form two-way physical barriers, cornified cell envelope (CCE), and tight junctions (TJs). While undifferentiated keratinocytes in the basal layer continuously deliver daughter cells outward, which undergo successive differentiation with losing their polarized characteristics, they retain the expression of several polarity proteins. In the present study, we revealed that the t-SNARE protein syntaxin3, a critical element for the formation of the apical compartment in simple epithelial cells, is required to confer the ability to organize the physical barriers on "poorly polarized" keratinocytes in epidermal outer layers. HaCaT keratinocytes with genetic ablation of syntaxin3 readily succumbed to hydrogen peroxide-induced cell death. Additionally, they lost the ability to organize TJ and CCE structures, accompanied by notable downregulation of transglutaminase1 and caspase14 (a cornification regulator) expression. These syntaxin3-knockout cells appeared to restore oxidative stress tolerance and functional TJ formation ability, in response to the inducible re-expression of exogenous syntaxin3. While plausible mechanisms underlying these phenomena remain unclear, syntaxin3, an apical polarity protein in the simple epithelia, has emerged as a potentially crucial element for barrier formation in poorly polarized keratinocytes in polarized epidermal tissue.
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Affiliation(s)
- Kaho Hayashi
- Department of Biomedical Sciences, Graduate School of Science and Technology, Kwansei Gakuin University, Gakuen-Uegahara, Sanda, 669-1330, Japan
| | - Sae Nozaki
- Department of Biomedical Sciences, Graduate School of Science and Technology, Kwansei Gakuin University, Gakuen-Uegahara, Sanda, 669-1330, Japan
| | - Kanako Tokushima
- Department of Biomedical Sciences, Graduate School of Science and Technology, Kwansei Gakuin University, Gakuen-Uegahara, Sanda, 669-1330, Japan
| | - Fumika Tanaka
- Department of Biomedical Sciences, Graduate School of Science and Technology, Kwansei Gakuin University, Gakuen-Uegahara, Sanda, 669-1330, Japan
| | - Yohei Hirai
- Department of Biomedical Sciences, Graduate School of Science and Technology, Kwansei Gakuin University, Gakuen-Uegahara, Sanda, 669-1330, Japan.
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7
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Perez-Hurtado M, Dao C, Saenz AE, Heidelberger R. Syntaxin 3 is haplosufficient for long-term photoreceptor survival in the mouse retina. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1208805. [PMID: 37609371 PMCID: PMC10443939 DOI: 10.3389/fopht.2023.1208805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Biallelic loss-of-function mutations in the syntaxin 3 gene have been linked to a severe retinal dystrophy in humans that presents in early childhood. In mouse models, biallelic inactivation of the syntaxin 3 gene in photoreceptors rapidly leads to their death. What is not known is whether a monoallelic syntaxin 3 loss-of-function mutation might cause photoreceptor loss with advancing age. To address this question, we compared the outer nuclear layer of older adult mice (≈ 20 months of age) that were heterozygous for syntaxin 3 with those of similarly-aged control mice. We found that the photoreceptor layer maintains its thickness in mice that are heterozygous for syntaxin 3 relative to controls and that photoreceptor somatic counts are comparable. In addition, dendritic sprouting of the rod bipolar cell dendrites into the outer nuclear layer, which occurs following the loss of functional rod targets, was similar between genotypes. Thus, syntaxin 3 appears to be haplosufficient for photoreceptor survival, even with advancing age.
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Affiliation(s)
- Mariajose Perez-Hurtado
- Department of Neurobiology and Anatomy, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth Houston), Houston, TX
| | - Calvin Dao
- Department of Neurobiology and Anatomy, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth Houston), Houston, TX
| | - Amanda E. Saenz
- Department of Neurobiology and Anatomy, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth Houston), Houston, TX
| | - Ruth Heidelberger
- Department of Neurobiology and Anatomy, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth Houston), Houston, TX
- The University of Texas MDAnderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences, Houston TX
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8
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Osorio-Perez RM, Rodríguez-Manzo G, Espinosa-Riquer ZP, Cruz SL, González-Espinosa C. Endocannabinoid modulation of allergic responses: Focus on the control of FcεRI-mediated mast cell activation. Eur J Cell Biol 2023; 102:151324. [PMID: 37236045 DOI: 10.1016/j.ejcb.2023.151324] [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: 12/23/2022] [Revised: 05/16/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
Allergic reactions are highly prevalent pathologies initiated by the production of IgE antibodies against harmless antigens (allergens) and the activation of the high-affinity IgE receptor (FcεRI) expressed in the surface of basophils and mast cells (MCs). Research on the mechanisms of negative control of those exacerbated inflammatory reactions has been intense in recent years. Endocannabinoids (eCBs) show important regulatory effects on MC-mediated immune responses, mainly inhibiting the production of pro-inflammatory mediators. However, the description of the molecular mechanisms involved in eCB control of MC activation is far from complete. In this review, we aim to summarize the available information regarding the role of eCBs in the modulation of FcεRI-dependent activation of that cell type, emphasizing the description of the eCB system and the existence of some of its elements in MCs. Unique characteristics of the eCB system and cannabinoid receptors (CBRs) localization and signaling in MCs are mentioned. The described and putative points of cross-talk between CBRs and FcεRI signaling cascades are also presented. Finally, we discuss some important considerations in the study of the effects of eCBs in MCs and the perspectives in the field.
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Affiliation(s)
- Rubi Monserrat Osorio-Perez
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Sede Sur, Calzada de los Tenorios No. 235, Col. Granjas Coapa, Tlalpan, CP 14330 Mexico City, Mexico
| | - Gabriela Rodríguez-Manzo
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Sede Sur, Calzada de los Tenorios No. 235, Col. Granjas Coapa, Tlalpan, CP 14330 Mexico City, Mexico
| | - Zyanya P Espinosa-Riquer
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Sede Sur, Calzada de los Tenorios No. 235, Col. Granjas Coapa, Tlalpan, CP 14330 Mexico City, Mexico
| | - Silvia L Cruz
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Sede Sur, Calzada de los Tenorios No. 235, Col. Granjas Coapa, Tlalpan, CP 14330 Mexico City, Mexico
| | - Claudia González-Espinosa
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del IPN, Unidad Sede Sur, Calzada de los Tenorios No. 235, Col. Granjas Coapa, Tlalpan, CP 14330 Mexico City, Mexico.
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9
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Adhikari P, Ayo TE, Vines JC, Sugita S, Xu H. Exocytic machineries differentially control mediator release from allergen-triggered RBL-2H3 cells. Inflamm Res 2023; 72:639-649. [PMID: 36725743 DOI: 10.1007/s00011-023-01698-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 01/06/2023] [Accepted: 01/23/2023] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Mast cells utilize SNAREs (soluble-N-ethyl-maleimide sensitive factor attachment protein receptors) and SM (Sec1/Munc18) proteins to secrete/exocytose a variety of proinflammatory mediators. However, whether a common SNARE-SM machinery is responsible remains unclear. METHODS Four vesicle/granule-anchored SNAREs (VAMP2, VAMP3, VAMP7, and VAMP8) and two Munc18 homologs (Munc18a and Munc18b) were systematically knocked down or knocked out in RBL-2H3 mast cells and antigen-induced release of β-hexosaminidase, histamine, serotonin, and TNF was examined. Phenotypes were validated by rescue experiments. Immunofluorescence studies were performed to determine the subcellular distribution of key players. RESULTS The reduction of VAMP8 expression inhibited the exocytosis of β-hexosaminidase, histamine, and serotonin but not TNF. Unexpectedly, however, confocal microscopy revealed substantial co-localization between VAMP8 and TNF, and between TNF and serotonin. Meanwhile, the depletion of other VAMPs, including knockout of VAMP3, had no impact on the release of any of the mediators examined. On the other hand, TNF exocytosis was diminished specifically in stable Munc18bknockdown cells, in a fashion that was rescued by exogenous, RNAi-resistant Munc18b. In line with this, TNF was co-localized with Munc18b (47%) to a much greater extent than with Munc18a (13%). CONCLUSION Distinct exocytic pathways exist in mast cells for the release of different mediators.
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Affiliation(s)
- Pratikshya Adhikari
- Center for Molecular and Cellular Biosciences, School of Biological, Environmental, and Earth Sciences, University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Tolulope E Ayo
- Center for Molecular and Cellular Biosciences, School of Biological, Environmental, and Earth Sciences, University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - John C Vines
- Center for Molecular and Cellular Biosciences, School of Biological, Environmental, and Earth Sciences, University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Shuzo Sugita
- Division of Fundamental Neurobiology, University Health Network, Toronto, ON, M5T 2S8, Canada
- Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Hao Xu
- Center for Molecular and Cellular Biosciences, School of Biological, Environmental, and Earth Sciences, University of Southern Mississippi, Hattiesburg, MS, 39406, USA.
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10
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Abstract
Mast cells originate from the CD34+/CD117+ hematopoietic progenitors in the bone marrow, migrate into circulation, and ultimately mature and reside in peripheral tissues. Microbiota/metabolites and certain immune cells (e.g., Treg cells) play a key role in maintaining immune tolerance. Cross-linking of allergen-specific IgE on mast cells activates the high-affinity membrane-bound receptor FcεRI, thereby initiating an intracellular signal cascade, leading to degranulation and release of pro-inflammatory mediators. The intracellular signal transduction is intricately regulated by various kinases, transcription factors, and cytokines. Importantly, multiple signal components in the FcεRI-mast cell–mediated allergic cascade can be targeted for therapeutic purposes. Pharmacological interventions that include therapeutic antibodies against IgE, FcεRI, and cytokines as well as inhibitors/activators of several key intracellular signaling molecues have been used to inhibit allergic reactions. Other factors that are not part of the signal pathway but can enhance an individual’s susceptibility to allergen stimulation are referred to as cofactors. Herein, we provide a mechanistic overview of the FcεRI-mast cell–mediated allergic signaling. This will broaden our scope and visions on specific preventive and therapeutic strategies for the clinical management of mast cell–associated hypersensitivity reactions.
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11
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Cui L, Li H, Xi Y, Hu Q, Liu H, Fan J, Xiang Y, Zhang X, Shui W, Lai Y. Vesicle trafficking and vesicle fusion: mechanisms, biological functions, and their implications for potential disease therapy. MOLECULAR BIOMEDICINE 2022; 3:29. [PMID: 36129576 PMCID: PMC9492833 DOI: 10.1186/s43556-022-00090-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/12/2022] [Indexed: 11/10/2022] Open
Abstract
Intracellular vesicle trafficking is the fundamental process to maintain the homeostasis of membrane-enclosed organelles in eukaryotic cells. These organelles transport cargo from the donor membrane to the target membrane through the cargo containing vesicles. Vesicle trafficking pathway includes vesicle formation from the donor membrane, vesicle transport, and vesicle fusion with the target membrane. Coat protein mediated vesicle formation is a delicate membrane budding process for cargo molecules selection and package into vesicle carriers. Vesicle transport is a dynamic and specific process for the cargo containing vesicles translocation from the donor membrane to the target membrane. This process requires a group of conserved proteins such as Rab GTPases, motor adaptors, and motor proteins to ensure vesicle transport along cytoskeletal track. Soluble N-ethyl-maleimide-sensitive factor (NSF) attachment protein receptors (SNARE)-mediated vesicle fusion is the final process for vesicle unloading the cargo molecules at the target membrane. To ensure vesicle fusion occurring at a defined position and time pattern in eukaryotic cell, multiple fusogenic proteins, such as synaptotagmin (Syt), complexin (Cpx), Munc13, Munc18 and other tethering factors, cooperate together to precisely regulate the process of vesicle fusion. Dysfunctions of the fusogenic proteins in SNARE-mediated vesicle fusion are closely related to many diseases. Recent studies have suggested that stimulated membrane fusion can be manipulated pharmacologically via disruption the interface between the SNARE complex and Ca2+ sensor protein. Here, we summarize recent insights into the molecular mechanisms of vesicle trafficking, and implications for the development of new therapeutics based on the manipulation of vesicle fusion.
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12
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Dolan B, Ermund A, Martinez-Abad B, Johansson ME, Hansson GC. Clearance of small intestinal crypts involves goblet cell mucus secretion by intracellular granule rupture and enterocyte ion transport. Sci Signal 2022; 15:eabl5848. [PMID: 36126118 PMCID: PMC9749883 DOI: 10.1126/scisignal.abl5848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Goblet cells in the small intestinal crypts contain large numbers of mucin granules that are rapidly discharged to clean bacteria from the crypt. Because acetylcholine released by neuronal and nonneuronal cells controls many aspects of intestinal epithelial function, we used tissue explants and organoids to investigate the response of the small intestinal crypt to cholinergic stimulation. The activation of muscarinic acetylcholine receptors initiated a coordinated and rapid emptying of crypt goblet cells that flushed the crypt contents into the intestinal lumen. Cholinergic stimulation induced an expansion of the granule contents followed by intracellular rupture of the mucin granules. The mucus expanded intracellularly before the rupture of the goblet cell apical membrane and continued to expand after its release into the crypt lumen. The goblet cells recovered from membrane rupture and replenished their stores of mucin granules. Mucus secretion from the goblet cells depended on Ca2+ signaling and the expansion of the mucus in the crypt depended on gap junctions and on ion and water transport by enterocytes adjacent to the goblet cells. This distinctive mode of mucus secretion, which we refer to as "expanding secretion," efficiently cleans the small intestine crypt through coordinated mucus, ion, and fluid secretion by goblet cells and enterocytes.
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Affiliation(s)
- Brendan Dolan
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Anna Ermund
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Beatriz Martinez-Abad
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Malin E.V. Johansson
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Gunnar C. Hansson
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
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13
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Lei F, Tian Y, Miao J, Pan L, Tong R, Zhou Y. Immunotoxicity pathway and mechanism of benzo[a]pyrene on hemocytes of Chlamys farreri in vitro. FISH & SHELLFISH IMMUNOLOGY 2022; 124:208-218. [PMID: 35413479 DOI: 10.1016/j.fsi.2022.04.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 04/04/2022] [Accepted: 04/06/2022] [Indexed: 06/14/2023]
Abstract
Benzo[a]pyrene (B[a]P), a typical PAHs widely existing in the marine environment, has been extensively studied for its immunotoxicity due to its persistence and high toxicity. Nevertheless, the immunotoxicity mechanism remain incompletely understood. In this study, isolated hemocytes of Chlamys farreri were exposed at three concentrations of B[a]P (5, 10 and 15 μg/mL), and the effects of B[a]P on detoxification metabolism, signal transduction, humoral immune factors, exocytosis and phagocytosis relevant proteins and immune function at 0, 6, 12, 24 h were studied. Results illustrated the AhR, ARNT and CYP1A1 were significantly induced by B[a]P at 12 h. Additionally, the content of B[a]P metabolite BPDE increased in a dose-dependent manner with pollutants. Under B[a]P stimulation, the expressions of PTK (Src, Fyn) and PLC-Ca2+-PKC pathway gene increased significantly, while the transcription level of AC-cAMP-PKA pathway gene decreased remarkably. Additionally, the expressions of nuclear transcription factors (CREB, NF-κB), complement system genes and C-type lectin genes up-regulated obviously. The gene expressions of phagocytosis and exocytosis related proteins were also notably affected. 5 μg/mL B[a]P could promote phagocytosis in a transitory time, but with the increase of exposure time and concentration of B[a]P, the phagocytosis, antibacterial and bacteriolytic activities gradually decreased. These results indicated that similar to vertebrates, BPDE, the metabolite of B[a]P, mediated downstream signal transduction via PTK in bivalves. The declined of the immune defense ability of hemocytes might be closely related to the inhibition of AC-cAMP-PKA pathway and the imbalance of intracellular Ca2+ pathway. In addition, the results manifested that complement and lectin systems play a significant role in regulating immune response. In this study, the direct relationship between detoxification metabolism and immune signal transduction in bivalves under B[a]P stress was demonstrated for the first time, which provided important information for the potential molecular mechanism of B[a]P-induced immune system disorder in bivalves.
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Affiliation(s)
- Fengjun Lei
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Yimeng Tian
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Jingjing Miao
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Luqing Pan
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China.
| | - Ruixue Tong
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
| | - Yueyao Zhou
- The Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, PR China
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14
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Perl E, Ravisankar P, Beerens ME, Mulahasanovic L, Smallwood K, Sasso MB, Wenzel C, Ryan TD, Komár M, Bove KE, MacRae CA, Weaver KN, Prada CE, Waxman JS. Stx4 is required to regulate cardiomyocyte Ca 2+ handling during vertebrate cardiac development. HGG ADVANCES 2022; 3:100115. [PMID: 35599850 PMCID: PMC9114686 DOI: 10.1016/j.xhgg.2022.100115] [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: 01/06/2022] [Accepted: 04/22/2022] [Indexed: 12/16/2022] Open
Abstract
Requirements for vesicle fusion within the heart remain poorly understood, despite the multitude of processes that necessitate proper intracellular trafficking within cardiomyocytes. Here, we show that Syntaxin 4 (STX4), a target-Soluble N-ethylmaleimide sensitive factor attachment receptor (t-SNARE) protein, is required for normal vertebrate cardiac conduction and vesicular transport. Two patients were identified with damaging variants in STX4. A patient with a homozygous R240W missense variant displayed biventricular dilated cardiomyopathy, ectopy, and runs of non-sustained ventricular tachycardia, sensorineural hearing loss, global developmental delay, and hypotonia, while a second patient displayed severe pleiotropic abnormalities and perinatal lethality. CRISPR/Cas9-generated stx4 mutant zebrafish exhibited defects reminiscent of these patients' clinical presentations, including linearized hearts, bradycardia, otic vesicle dysgenesis, neuronal atrophy, and touch insensitivity by 3 days post fertilization. Imaging of Vamp2+ vesicles within stx4 mutant zebrafish hearts showed reduced docking to the cardiomyocyte sarcolemma. Optical mapping of the embryonic hearts coupled with pharmacological modulation of Ca2+ handling together support that zebrafish stx4 mutants have a reduction in L-type Ca2+ channel modulation. Transgenic overexpression of zebrafish Stx4R241W, analogous to the first patient's STX4R240W variant, indicated that the variant is hypomorphic. Thus, these data show an in vivo requirement for SNAREs in regulating normal embryonic cardiac function and that variants in STX4 are associated with pleiotropic human disease, including cardiomyopathy.
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Affiliation(s)
- Eliyahu Perl
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, OH, USA,Molecular and Developmental Biology Graduate Program, University of Cincinnati College of Medicine, Cincinnati, OH, USA,Division of Molecular Cardiovascular Biology, The Heart Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Padmapriyadarshini Ravisankar
- Division of Molecular Cardiovascular Biology, The Heart Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Manu E. Beerens
- Cardiovascular Medicine Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA
| | - Lejla Mulahasanovic
- Praxis für Humangenetik, Tübingen, Baden-Württemberg, Germany,CeGaT GmbH, Tübingen, Baden-Württemberg, Germany
| | - Kelly Smallwood
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Marion Bermúdez Sasso
- Institute for Clinical Genetics, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Saxony, Germany
| | - Carina Wenzel
- Institute of Pathology, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany
| | - Thomas D. Ryan
- Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH, USA,Heart Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA
| | - Matej Komár
- Department of Gynecology and Obstetrics, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Saxony, Germany
| | - Kevin E. Bove
- Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH, USA,Division of Pathology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA,Department of Pathology and Laboratory Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Calum A. MacRae
- Cardiovascular Medicine Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA,Genetics and Network Medicine Divisions, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA,Harvard Stem Cell Institute, Boston, MA, USA
| | - K. Nicole Weaver
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA,Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Carlos E. Prada
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA,Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Joshua S. Waxman
- Division of Molecular Cardiovascular Biology, The Heart Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA,Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH, USA,Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, USA,Corresponding author
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15
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Zhang Y, Dho SE, Othman K, Simpson CD, Lapierre J, Bondoc A, McGlade CJ. Numb exon 9 inclusion regulates Integrinβ5 surface expression and promotes breast cancer metastasis. Oncogene 2022; 41:2079-2094. [PMID: 35181737 DOI: 10.1038/s41388-022-02225-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 01/14/2022] [Accepted: 02/01/2022] [Indexed: 01/07/2023]
Abstract
The endocytic adaptor protein Numb acts as a tumor suppressor through downregulation of oncogenic pathways in multiple cancer types. The identification of splicing alterations giving rise to changes in Numb protein isoform expression indicate that Numb also has tumor promoting activity, though the underlying mechanisms are unknown. Here we report that NUMB exon 9 inclusion, which results in production of a protein isoform with an additional 49 amino acids, is a feature of multiple cancer types including all subtypes of breast cancer and correlates with worse progression-free survival. Specific deletion of exon 9-included Numb isoforms (Exon9in) from breast cancer cells reduced cell growth and prevents spontaneous lung metastasis in a mouse model. Quantitative proteome profiling showed that loss of Exon9in causes downregulation of membrane receptors and adhesion molecules, as well as proteins involved in extracellular matrix organization and the epithelial-mesenchymal transition (EMT) state. In addition, exon 9 deletion caused remodeling of the endocytic network, decreased ITGβ5 surface localization, cell spreading on vitronectin and downstream signaling to ERK and SRC. Together these observations suggest that Exon9in isoform expression disrupts the endocytic trafficking functions of Numb, resulting in increased surface expression of ITGβ5 as well as other plasma membrane proteins to promote cell adhesion, EMT, and tumor metastasis.
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Affiliation(s)
- Yangjing Zhang
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON, M5G 2M9, Canada
- The Arthur and Sonia Labatt Brain Tumour Research Centre, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Sascha E Dho
- The Arthur and Sonia Labatt Brain Tumour Research Centre, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
- Program in Cell Biology, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Kamal Othman
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON, M5G 2M9, Canada
- The Arthur and Sonia Labatt Brain Tumour Research Centre, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Craig D Simpson
- SPARC BioCentre, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Jessica Lapierre
- The Arthur and Sonia Labatt Brain Tumour Research Centre, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
- Program in Cell Biology, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - Andrew Bondoc
- The Arthur and Sonia Labatt Brain Tumour Research Centre, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
- Program in Cell Biology, 555 University Avenue, Toronto, ON, M5G 1X8, Canada
| | - C Jane McGlade
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON, M5G 2M9, Canada.
- The Arthur and Sonia Labatt Brain Tumour Research Centre, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
- Program in Cell Biology, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
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16
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Alam SB, Kulka M. Internalization of benzylisoquinoline alkaloids by resting and activated bone marrow-derived mast cells utilizes energy-dependent mechanisms. Inflamm Res 2022; 71:343-356. [PMID: 35076750 PMCID: PMC8897387 DOI: 10.1007/s00011-021-01526-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 11/15/2021] [Accepted: 11/22/2021] [Indexed: 11/24/2022] Open
Abstract
Objective and design Drug delivery to inflammatory cells is dependent upon poorly understood, complex endocytic processes. Berberine (BBR), a benzylisoquinoline alkaloid, binds to heparin and targets glycosaminoglycan-rich granules in mast cells (MC), but the mechanism of BBR internalization is unknown. Methods BMMC were treated with various concentrations of BBR for different amounts of time and BBR internalization was assessed by flow cytometry and fluorescence microscopy. BMMC were pretreated with endocytic inhibitors or a growth factor (IL-3) prior to BBR exposure to access mechanisms of its internalization. Results After 24 h, 48 ± 0.8% of BMMC internalized BBR and this process was dependent upon temperature and the presence of glucose in the medium. Methanol fixation reduced BBR internalization, suggesting the involvement of an energy-dependent active transport mechanism. To determine mode of internalization, BBR was encapsulated into Lipofectamine TM lipoplexes since these are known to circumvent classical endocytic pathways. Incorporating BBR into lipoplexes decreased BBR internalization by 26% and 10% (10 μg/ml and 100 μg/ml Lipo-BBR respectively) by BMMC. BBR endocytosis was significantly reduced by Latrunculin B (88%), Cytochalasin B (87%), Chloroquine (86.5%) and 3-methyladenine (91%), indicating that actin polymerization, lysosomal pH and lysosomal self-degradation via the autophagy pathway was involved. In contrast, IL-3 treatment significantly enhanced BBR endocytosis (54% by 40 ng/ml IL-3) suggesting that IL-3 signaling pathways play a role in internalization. Conclusions Our data suggests that internalization of BBR by resting and IL-3-activated BMMC utilizes an energy-dependent pathway that is dependent upon glucose metabolism and temperature. Furthermore, this process requires actin polymerization and lysosomal trafficking. These data suggest internalization of benzylisoquinoline compounds is an active and complex process. Supplementary Information The online version contains supplementary material available at 10.1007/s00011-021-01526-2.
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Affiliation(s)
- Syed Benazir Alam
- Nanotechnology Research Centre, National Research Council Canada, 11421 Saskatchewan Dr NW, Edmonton, AB, T6G 2M9, Canada
| | - Marianna Kulka
- Nanotechnology Research Centre, National Research Council Canada, 11421 Saskatchewan Dr NW, Edmonton, AB, T6G 2M9, Canada.
- Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada.
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17
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Rajani HF, Shahidi S, Gomari MM. Protein and Antibody Engineering: Suppressing Degranulation of the Mast Cells and Type I Hypersensitivity Reaction. Curr Protein Pept Sci 2021; 21:831-841. [PMID: 32392111 DOI: 10.2174/1389203721666200511094717] [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: 01/10/2020] [Revised: 03/09/2020] [Accepted: 04/23/2020] [Indexed: 11/22/2022]
Abstract
With an increase in atopic cases and owing to a significant role of mast cells in type I hypersensitivity, a therapeutic need to inhibit degranulation of mast cells has risen. Mast cells are notorious for IgE-mediated allergic response. Advancements have allowed researchers to improve clinical outcomes of already available therapies. Engineered peptides and antibodies can be easily manipulated to attain desired characteristics as per the biological environment. A number of these molecules are designed to target mast cells in order to regulate the release of histamine and other mediators, thereby controlling type I hypersensitivity response. The aim of this review paper is to highlight some of the significant molecules designed for the purpose.
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Affiliation(s)
- Huda Fatima Rajani
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical
Sciences, Tehran, Iran
| | - Solmaz Shahidi
- Department of Clinical Biochemistry, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Mahmoudi Gomari
- Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical
Sciences, Tehran, Iran
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18
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Janecke AR, Liu X, Adam R, Punuru S, Viestenz A, Strauß V, Laass M, Sanchez E, Adachi R, Schatz MP, Saboo US, Mittal N, Rohrschneider K, Escher J, Ganesh A, Al Zuhaibi S, Al Murshedi F, AlSaleem B, Alfadhel M, Al Sinani S, Alkuraya FS, Huber LA, Müller T, Heidelberger R, Janz R. Pathogenic STX3 variants affecting the retinal and intestinal transcripts cause an early-onset severe retinal dystrophy in microvillus inclusion disease subjects. Hum Genet 2021; 140:1143-1156. [PMID: 33974130 PMCID: PMC8263458 DOI: 10.1007/s00439-021-02284-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/15/2021] [Indexed: 01/12/2023]
Abstract
Biallelic STX3 variants were previously reported in five individuals with the severe congenital enteropathy, microvillus inclusion disease (MVID). Here, we provide a significant extension of the phenotypic spectrum caused by STX3 variants. We report ten individuals of diverse geographic origin with biallelic STX3 loss-of-function variants, identified through exome sequencing, single-nucleotide polymorphism array-based homozygosity mapping, and international collaboration. The evaluated individuals all presented with MVID. Eight individuals also displayed early-onset severe retinal dystrophy, i.e., syndromic-intestinal and retinal-disease. These individuals harbored STX3 variants that affected both the retinal and intestinal STX3 transcripts, whereas STX3 variants affected only the intestinal transcript in individuals with solitary MVID. That STX3 is essential for retinal photoreceptor survival was confirmed by the creation of a rod photoreceptor-specific STX3 knockout mouse model which revealed a time-dependent reduction in the number of rod photoreceptors, thinning of the outer nuclear layer, and the eventual loss of both rod and cone photoreceptors. Together, our results provide a link between STX3 loss-of-function variants and a human retinal dystrophy. Depending on the genomic site of a human loss-of-function STX3 variant, it can cause MVID, the novel intestinal-retinal syndrome reported here or, hypothetically, an isolated retinal dystrophy.
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Affiliation(s)
- Andreas R Janecke
- Department of Pediatrics I, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria.
- Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria.
| | - Xiaoqin Liu
- Department of Neurobiology and Anatomy, MSB 7.046, McGovern Medical School at the University of Texas HSC (UTHealth), 6431 Fannin Street, Houston, TX, 77030, USA
| | - Rüdiger Adam
- University Children's Hospital, Medical Faculty Mannheim, Heidelberg University, 68167 Mannheim, Germany
| | - Sumanth Punuru
- Department of Neurobiology and Anatomy, MSB 7.046, McGovern Medical School at the University of Texas HSC (UTHealth), 6431 Fannin Street, Houston, TX, 77030, USA
| | - Arne Viestenz
- Department of Ophthalmology, University Medical Center Halle, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Valeria Strauß
- Klinik für Kinder- und Jugendmedizin, Universitätsklinikum Halle, Halle, Germany
| | - Martin Laass
- Klinik und Poliklinik f. Kinder- u. Jugendmedizin, University of Dresden, Dresden, Germany
| | - Elizabeth Sanchez
- Department of Pulmonary Medicine, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Roberto Adachi
- Department of Pulmonary Medicine, Division of Internal Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Martha P Schatz
- Department of Ophthalmology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Ujwala S Saboo
- Department of Ophthalmology, University of Texas Health Science Center, San Antonio, TX, USA
| | - Naveen Mittal
- Department of Department of Pediatrics, Division of Pediatric Gastroenterology, University of Texas Health Science Center, San Antonio, TX, USA
| | | | - Johanna Escher
- Erasmus MC-Sophia Children's Hospital, Rotterdam, The Netherlands
| | - Anuradha Ganesh
- Department of Ophthalmology, Sultan Qaboos University Hospital, Muscat, Oman
| | - Sana Al Zuhaibi
- Department of Ophthalmology, Sultan Qaboos University Hospital, Muscat, Oman
| | - Fathiya Al Murshedi
- Genetic and Developmental Medicine Clinic, Sultan Qaboos University Hospital, Muscat, Oman
| | - Badr AlSaleem
- King Fahad Medical City, Children's Specialized Hospital, Riyadh, Saudi Arabia
| | - Majid Alfadhel
- Genetics Division and Medical Genomic Research Lab, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
| | - Siham Al Sinani
- Department of Child Health, Sultan Qaboos University Hospital, Muscat, Oman
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Lukas A Huber
- Division of Cell Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Thomas Müller
- Department of Pediatrics I, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria
| | - Ruth Heidelberger
- Department of Neurobiology and Anatomy, MSB 7.046, McGovern Medical School at the University of Texas HSC (UTHealth), 6431 Fannin Street, Houston, TX, 77030, USA.
| | - Roger Janz
- Department of Neurobiology and Anatomy, MSB 7.046, McGovern Medical School at the University of Texas HSC (UTHealth), 6431 Fannin Street, Houston, TX, 77030, USA
- Center for Scientific Review, National Institutes of Health, Bethesda, MD, USA
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19
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Blank U, Huang H, Kawakami T. The high affinity IgE receptor: a signaling update. Curr Opin Immunol 2021; 72:51-58. [PMID: 33838574 DOI: 10.1016/j.coi.2021.03.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 03/22/2021] [Indexed: 01/01/2023]
Abstract
Here we update receptor proximal and distant signaling events of the mast cell high affinity IgE receptor (FcεRI) launching immediate type I hypersensitivity and an inflammatory cytokine-chemokine cascade. Different physiologic antigen concentrations, their affinity, and valency for the IgE ligand produce distinct intracellular signaling events with different outcomes. Investigating mast cell degranulation has revealed a complex molecular machinery that relays proximal signaling to cytoskeletal reorganization, granule transport and membrane fusion. Several new phosphorylation- and calcium-responsive effectors have been described. FcεRI signaling also promotes de novo gene transcription. Recent progress has identified enhancers at genes that are upregulated in mast cells after stimulation through FcεRI using next generation sequencing methods. Enhancers at genes that respond to antigenic stimulation in human mast cells revealed Ca2+-dependency. Stimulation-responsive super enhancers in mouse mast cells have also been identified. Mast cell lineage-determining transcription factor GATA2 primes these enhancers to respond to antigenic stimulation.
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Affiliation(s)
- Ulrich Blank
- Université de Paris, Centre de Recherche sur l'Inflammation, INSERM UMR1149, CNRS ERL8252, Faculté de Médecine site Bichat, Paris, France; Laboratoire d'Excellence Inflamex, Paris, France.
| | - Hua Huang
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO 80206, USA; Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Toshiaki Kawakami
- Laboratory of Allergic Diseases, Center for Autoimmunity and Inflammation, La Jolla Institute for Immunology, La Jolla, CA 92037, USA; Department of Dermatology, School of Medicine, University of California San Diego, La Jolla, CA 92093, USA
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20
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Ménasché G, Longé C, Bratti M, Blank U. Cytoskeletal Transport, Reorganization, and Fusion Regulation in Mast Cell-Stimulus Secretion Coupling. Front Cell Dev Biol 2021; 9:652077. [PMID: 33796537 PMCID: PMC8007931 DOI: 10.3389/fcell.2021.652077] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 02/03/2021] [Indexed: 01/16/2023] Open
Abstract
Mast cells are well known for their role in allergies and many chronic inflammatory diseases. They release upon stimulation, e.g., via the IgE receptor, numerous bioactive compounds from cytoplasmic secretory granules. The regulation of granule secretion and its interaction with the cytoskeleton and transport mechanisms has only recently begun to be understood. These studies have provided new insight into the interaction between the secretory machinery and cytoskeletal elements in the regulation of the degranulation process. They suggest a tight coupling of these two systems, implying a series of specific signaling effectors and adaptor molecules. Here we review recent knowledge describing the signaling events regulating cytoskeletal reorganization and secretory granule transport machinery in conjunction with the membrane fusion machinery that occur during mast cell degranulation. The new insight into MC biology offers novel strategies to treat human allergic and inflammatory diseases targeting the late steps that affect harmful release from granular stores leaving regulatory cytokine secretion intact.
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Affiliation(s)
- Gaël Ménasché
- Laboratory of Molecular Basis of Altered Immune Homeostasis, Imagine Institute, INSERM UMR 1163, Université de Paris, Paris, France
| | - Cyril Longé
- Laboratory of Molecular Basis of Altered Immune Homeostasis, Imagine Institute, INSERM UMR 1163, Université de Paris, Paris, France
| | - Manuela Bratti
- Centre de Recherche sur l'Inflammation, INSERM UMR 1149, CNRS ERL8252, Faculté de Médecine site Bichat, Université de Paris, Paris, France.,Laboratoire d'Excellence Inflamex, Université de Paris, Paris, France
| | - Ulrich Blank
- Centre de Recherche sur l'Inflammation, INSERM UMR 1149, CNRS ERL8252, Faculté de Médecine site Bichat, Université de Paris, Paris, France.,Laboratoire d'Excellence Inflamex, Université de Paris, Paris, France
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21
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Frasca D, Romero M, Garcia D, Diaz A, Blomberg BB. Hyper-metabolic B cells in the spleens of old mice make antibodies with autoimmune specificities. Immun Ageing 2021; 18:9. [PMID: 33639971 PMCID: PMC7916295 DOI: 10.1186/s12979-021-00222-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/18/2021] [Indexed: 12/30/2022]
Abstract
BACKGROUND Aging is associated with increased intrinsic B cell inflammation, decreased protective antibody responses and increased autoimmune antibody responses. The effects of aging on the metabolic phenotype of B cells and on the metabolic programs that lead to the secretion of protective versus autoimmune antibodies are not known. METHODS Splenic B cells and the major splenic B cell subsets, Follicular (FO) and Age-associated B cells (ABCs), were isolated from the spleens of young and old mice and left unstimulated. The RNA was collected to measure the expression of markers associated with intrinsic inflammation and autoimmune antibody production by qPCR. B cells and B cell subsets were also stimulated with CpG and supernatants collected after 7 days to measure autoimmune IgG secretion by ELISA. Metabolic measures (oxygen consumption rate, extracellular acidification rate and glucose uptake) were performed using a Seahorse XFp extracellular flux analyzer. RESULTS Results have identified the subset of ABCs, whose frequencies and numbers increase with age and represent the most pro-inflammatory B cell subset, as the cell type mainly if not exclusively responsible for the expression of inflammatory markers and for the secretion of autoimmune antibodies in the spleen of old mice. Hyper-inflammatory ABCs from old mice are also hyper-metabolic, as compared to those from young mice and to the subset of FO B cells, a feature needed not only to support their higher expression of RNA for inflammatory markers but also their higher autoimmune antibody secretion. CONCLUSIONS These results identify a relationship between intrinsic inflammation, metabolism and autoimmune B cells and suggest possible ways to understand cellular mechanisms that lead to the generation of pathogenic B cells, that are hyper-inflammatory and hyper-metabolic, and secrete IgG antibodies with autoimmune specificities.
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Affiliation(s)
- Daniela Frasca
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, RMSB 3146A, 1600 NW 10th Ave, FL, 33136, Miami, USA.
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA.
| | - Maria Romero
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, RMSB 3146A, 1600 NW 10th Ave, FL, 33136, Miami, USA
| | - Denisse Garcia
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, RMSB 3146A, 1600 NW 10th Ave, FL, 33136, Miami, USA
| | - Alain Diaz
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, RMSB 3146A, 1600 NW 10th Ave, FL, 33136, Miami, USA
| | - Bonnie B Blomberg
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, RMSB 3146A, 1600 NW 10th Ave, FL, 33136, Miami, USA
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
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SNAP23 is essential for platelet and mast cell development and required in connective tissue mast cells for anaphylaxis. J Biol Chem 2021; 296:100268. [PMID: 33837726 PMCID: PMC7948755 DOI: 10.1016/j.jbc.2021.100268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 12/31/2020] [Accepted: 01/06/2021] [Indexed: 11/23/2022] Open
Abstract
Degranulation, a fundamental effector response from mast cells (MCs) and platelets, is an example of regulated exocytosis. This process is mediated by SNARE proteins and their regulators. We have previously shown that several of these proteins are essential for exocytosis in MCs and platelets. Here, we assessed the role of the SNARE protein SNAP23 using conditional knockout mice, in which SNAP23 was selectively deleted from either the megakaryocyte/platelet or connective tissue MC lineages. We found that removal of SNAP23 in platelets results in severe defects in degranulation of all three platelet secretory granule types, i.e., alpha, dense, and lysosomal granules. The mutation also induces thrombocytopenia, abnormal platelet morphology and activation, and reduction in the number of alpha granules. Therefore, the degranulation defect might not be secondary to an intrinsic failure of the machinery mediating regulated exocytosis in platelets. When we removed SNAP23 expression in MCs, there was a complete developmental failure in vitro and in vivo. The developmental defects in platelets and MCs and the abnormal translocation of membrane proteins to the surface of platelets indicate that SNAP23 is also involved in constitutive exocytosis in these cells. The MC conditional deletant animals lacked connective tissue MCs, but their mucosal MCs were normal and expanded in response to an antigenic stimulus. We used this mouse to show that connective tissue MCs are required and mucosal MCs are not sufficient for an anaphylactic response.
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Syntaxin 3 is essential for photoreceptor outer segment protein trafficking and survival. Proc Natl Acad Sci U S A 2020; 117:20615-20624. [PMID: 32778589 DOI: 10.1073/pnas.2010751117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Trafficking of photoreceptor membrane proteins from their site of synthesis in the inner segment (IS) to the outer segment (OS) is critical for photoreceptor function and vision. Here we evaluate the role of syntaxin 3 (STX3), in trafficking of OS membrane proteins such as peripherin 2 (PRPH2) and rhodopsin. Photoreceptor-specific Stx3 knockouts [Stx3 f/f(iCre75) and Stx3 f/f(CRX-Cre) ] exhibited rapid, early-onset photoreceptor degeneration and functional decline characterized by structural defects in IS, OS, and synaptic terminals. Critically, in the absence of STX3, OS proteins such as PRPH2, the PRPH2 binding partner, rod outer segment membrane protein 1 (ROM1), and rhodopsin were mislocalized along the microtubules to the IS, cell body, and synaptic region. We find that the PRPH2 C-terminal domain interacts with STX3 as well as other photoreceptor SNAREs, and our findings indicate that STX3 is an essential part of the trafficking pathway for both disc (rhodopsin) and rim (PRPH2/ROM1) components of the OS.
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Shi S, Ma K, Bin NR, Harada H, Xie X, Huang M, Liu H, Lee S, Wang XF, Adachi R, Monnier PP, Zhang L, Sugita S. Syntaxin-3 is dispensable for basal neurotransmission and synaptic plasticity in postsynaptic hippocampal CA1 neurons. Sci Rep 2020; 10:709. [PMID: 31959797 PMCID: PMC6971263 DOI: 10.1038/s41598-019-57388-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/30/2019] [Indexed: 01/17/2023] Open
Abstract
Recent evidence suggests that SNARE fusion machinery play critical roles in postsynaptic neurotransmitter receptor trafficking, which is essential for synaptic plasticity. However, the key SNAREs involved remain highly controversial; syntaxin-3 and syntaxin-4 are leading candidates for the syntaxin isoform underlying postsynaptic plasticity. In a previous study, we showed that pyramidal-neuron specific conditional knockout (cKO) of syntaxin-4 significantly reduces basal transmission, synaptic plasticity and impairs postsynaptic receptor trafficking. However, this does not exclude a role for syntaxin-3 in such processes. Here, we generated and analyzed syntaxin-3 cKO mice. Extracellular field recordings in hippocampal slices showed that syntaxin-3 cKO did not exhibit significant changes in CA1 basal neurotransmission or in paired-pulse ratios. Importantly, there were no observed differences during LTP in comparison to control mice. Syntaxin-3 cKO mice performed similarly as the controls in spatial and contextual learning tasks. Consistent with the minimal effects of syntaxin-3 cKO, syntaxin-3 mRNA level was very low in hippocampal and cortex pyramidal neurons, but strongly expressed in the corpus callosum and caudate axon fibers. Together, our data suggest that syntaxin-3 is dispensable for hippocampal basal neurotransmission and synaptic plasticity, and further supports the notion that syntaxin-4 is the major isoform mediating these processes.
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Affiliation(s)
- Shan Shi
- Department of Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China.,Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada
| | - Ke Ma
- Department of Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China. .,Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.
| | - Na-Ryum Bin
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Hidekiyo Harada
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Ontario, M5T 2S8, Canada
| | - Xiaoyu Xie
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Anesthesiology, Dalian Medical University, Dalian, Liaoning, 116044, China
| | - Mengjia Huang
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Haiyu Liu
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Neurosurgery, The First Hospital of Jilin University, Changchun, 130021, China
| | - Soomin Lee
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Xue Fan Wang
- Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.,Division of Genetics and Development, Krembil Research Institute, University Health Network, Ontario, M5T 2S8, Canada
| | - Roberto Adachi
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, 77030, USA
| | - Philippe P Monnier
- Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.,Division of Genetics and Development, Krembil Research Institute, University Health Network, Ontario, M5T 2S8, Canada.,Department of Ophthalmology & Vision Sciences, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Liang Zhang
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada.,Department of Medicine, Faculty of Medicine, University of Toronto, Toronto, Ontario, M5S 1A8, Canada
| | - Shuzo Sugita
- Division of Fundamental Neurobiology, Krembil Research Institute, University Health Network, Toronto, Ontario, M5T 2S8, Canada. .,Department of Physiology, University of Toronto, Toronto, Ontario, M5S 1A8, Canada.
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Hays CL, Grassmeyer JJ, Wen X, Janz R, Heidelberger R, Thoreson WB. Simultaneous Release of Multiple Vesicles from Rods Involves Synaptic Ribbons and Syntaxin 3B. Biophys J 2019; 118:967-979. [PMID: 31653448 DOI: 10.1016/j.bpj.2019.10.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/25/2019] [Accepted: 10/03/2019] [Indexed: 02/05/2023] Open
Abstract
First proposed as a specialized mode of release at sensory neurons possessing ribbon synapses, multivesicular release has since been described throughout the central nervous system. Many aspects of multivesicular release remain poorly understood. We explored mechanisms underlying simultaneous multivesicular release at ribbon synapses in salamander retinal rod photoreceptors. We assessed spontaneous release presynaptically by recording glutamate transporter anion currents (IA(glu)) in rods. Spontaneous IA(glu) events were correlated in amplitude and kinetics with simultaneously measured miniature excitatory postsynaptic currents in horizontal cells. Both measures indicated that a significant fraction of events is multiquantal, with an analysis of IA(glu) revealing that multivesicular release constitutes ∼30% of spontaneous release events. IA(glu) charge transfer increased linearly with event amplitude showing that larger events involve greater glutamate release. The kinetics of large and small IA(glu) events were identical as were rise times of large and small miniature excitatory postsynaptic currents, indicating that the release of multiple vesicles during large events is highly synchronized. Effects of exogenous Ca2+ buffers suggested that multiquantal, but not uniquantal, release occurs preferentially near Ca2+ channels clustered beneath synaptic ribbons. Photoinactivation of ribbons reduced the frequency of spontaneous multiquantal events without affecting uniquantal release frequency, showing that spontaneous multiquantal release requires functional ribbons. Although both occur at ribbon-style active zones, the absence of cross-depletion indicates that evoked and spontaneous multiquantal release from ribbons involve different vesicle pools. Introducing an inhibitory peptide into rods to interfere with the SNARE protein, syntaxin 3B, selectively reduced multiquantal event frequency. These results support the hypothesis that simultaneous multiquantal release from rods arises from homotypic fusion among neighboring vesicles on ribbons and involves syntaxin 3B.
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Affiliation(s)
- Cassandra L Hays
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, Nebraska; Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska
| | - Justin J Grassmeyer
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska
| | - Xiangyi Wen
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; West China Hospital, Sichuan University, Chengdu, Sichuan, P.R. China
| | - Roger Janz
- Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas; The University of Texas MD Anderson Cancer Center University of Texas Health Graduate School of Biomedical Sciences, Houston, Texas
| | - Ruth Heidelberger
- Department of Neurobiology and Anatomy, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas; The University of Texas MD Anderson Cancer Center University of Texas Health Graduate School of Biomedical Sciences, Houston, Texas
| | - Wallace B Thoreson
- Department of Ophthalmology and Visual Sciences, Truhlsen Eye Institute, University of Nebraska Medical Center, Omaha, Nebraska; Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska.
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26
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Miller RL, Shtessel M, Robinson LB, Banerji A. Advances in drug allergy, urticaria, angioedema, and anaphylaxis in 2018. J Allergy Clin Immunol 2019; 144:381-392. [PMID: 31247266 DOI: 10.1016/j.jaci.2019.06.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 05/22/2019] [Accepted: 06/18/2019] [Indexed: 12/11/2022]
Abstract
Many notable advances in drug allergy, urticaria, angioedema, and anaphylaxis were reported in 2018. Broad-spectrum antibiotic use and, consequently, antibiotic resistance are widespread, and algorithms to clarify β-lactam allergy and optimize antibiotic use were described. Meaningful data emerged on the pathogenesis of delayed drug hypersensitivity reactions. Progress not only in defining biomarkers but also in understanding the effect on quality of life and developing better treatments has been made for patients with chronic idiopathic urticaria. Patients with hereditary angioedema (HAE) have gained additional access to highly efficacious therapies, with associated improvements in quality of life, and some progress was made in our understanding of recurrent angioedema in patients with normal laboratory results. Guidelines have defined clear goals to help providers optimize therapies in patients with HAE. The epidemiology and triggers of anaphylaxis and the mechanisms underlying anaphylaxis were elucidated further. In summary, these disorders (and labels) cause substantial burdens for individual persons and even society. Fortunately, publications in 2018 have informed on advancements in diagnosis and management and have provided better understanding of mechanisms that potentially could yield new therapies. This progress should lead to better health outcomes and paths forward in patients with drug allergy, urticaria, HAE, and anaphylaxis.
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Affiliation(s)
- Rachel L Miller
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Columbia University Vagelos College of Physicians and Surgeons, New York, NY; Division of Allergy, Immunology, and Rheumatology, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY.
| | - Maria Shtessel
- Division of Allergy, Immunology, and Rheumatology, Department of Pediatrics, Columbia University Vagelos College of Physicians and Surgeons, New York, NY
| | - Lacey B Robinson
- Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, Boston, Mass
| | - Aleena Banerji
- Division of Rheumatology, Allergy and Immunology, Department of Medicine, Massachusetts General Hospital, Boston, Mass
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