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Kekou K, Svingou M, Vogiatzakis N, Nitsa E, Veltra D, Marinakis NM, Tilemis FN, Tzetis M, Mitrakos A, Tsaroucha C, Selenti N, Papadimas GK, Papadopoulos C, Traeger-Synodinos J, Lochmuller H, Sofocleous C. Retrospective analysis of persistent HyperCKemia with or without muscle weakness in a case series from Greece highlights vast DMD variant heterogeneity. Expert Rev Mol Diagn 2023; 23:999-1010. [PMID: 37754746 DOI: 10.1080/14737159.2023.2264181] [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: 03/27/2023] [Accepted: 09/25/2023] [Indexed: 09/28/2023]
Abstract
BACKGROUND Persistent hyperCKemia results from muscle dysfunction often attributed to genetic alterations of muscle-related genes, such as the dystrophin gene (DMD). Retrospective assessment of findings from DMD analysis, in association with persistent HyperCKemia, was conducted. PATIENTS AND METHODS Evaluation of medical records from 1354 unrelated cases referred during the period 1996-2021. Assessment of data concerning the detection of DMD gene rearrangements and nucleotide variants. RESULTS A total of 730 individuals (657 cases, 569 of Greek and 88 of Albanian origins) were identified, allowing an overall estimation of dystrophinopathy incidence at ~1:3800 live male births. The heterogeneous spectrum of 275 distinct DMD alterations comprised exon(s) deletions/duplications, nucleotide variants, and rare events, such as chromosome translocation {t(X;20)}, contiguous gene deletions, and a fused gene involving the DMD and the DOCK8 genes. Ethnic-specific findings include a common founder variant in exon 36 ('Hellenic' variant). CONCLUSIONS Some 50% of hyperCKemia cases were characterized as dystrophinopathies, highlighting that DMD variants may be considered the most common cause of hyperCKemia in Greece. Delineation of the broad genetic and clinical heterogeneity is fundamental for actionable public health decisions and theragnosis, as well as the establishment of guidelines addressing ethical considerations, especially related to the mild asymptomatic patient subgroup.
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Wang XT, Zhou L, Dong BB, Xu FX, Wang DJ, Shen EW, Cai XY, Wang Y, Wang N, Ji SJ, Chen W, Schonewille M, Zhu JJ, De Zeeuw CI, Shen Y. cAMP-EPAC-PKCε-RIM1α signaling regulates presynaptic long-term potentiation and motor learning. eLife 2023; 12:e80875. [PMID: 37159499 PMCID: PMC10171863 DOI: 10.7554/elife.80875] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 04/25/2023] [Indexed: 05/11/2023] Open
Abstract
The cerebellum is involved in learning of fine motor skills, yet whether presynaptic plasticity contributes to such learning remains elusive. Here, we report that the EPAC-PKCε module has a critical role in a presynaptic form of long-term potentiation in the cerebellum and motor behavior in mice. Presynaptic cAMP-EPAC-PKCε signaling cascade induces a previously unidentified threonine phosphorylation of RIM1α, and thereby initiates the assembly of the Rab3A-RIM1α-Munc13-1 tripartite complex that facilitates docking and release of synaptic vesicles. Granule cell-specific blocking of EPAC-PKCε signaling abolishes presynaptic long-term potentiation at the parallel fiber to Purkinje cell synapses and impairs basic performance and learning of cerebellar motor behavior. These results unveil a functional relevance of presynaptic plasticity that is regulated through a novel signaling cascade, thereby enriching the spectrum of cerebellar learning mechanisms.
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Gupta M, Walters B, Katsara O, Granados Blanco K, Geter P, Schneider R. eIF2Bδ blocks the integrated stress response and maintains eIF2B activity and cancer metastasis by overexpression in breast cancer stem cells. Proc Natl Acad Sci U S A 2023; 120:e2207898120. [PMID: 37014850 PMCID: PMC10104532 DOI: 10.1073/pnas.2207898120] [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: 05/06/2022] [Accepted: 03/08/2023] [Indexed: 04/05/2023] Open
Abstract
Breast cancer (BC) metastasis involves cancer stem cells (CSCs) and their regulation by micro-RNAs (miRs), but miR targeting of the translation machinery in CSCs is poorly explored. We therefore screened miR expression levels in a range of BC cell lines, comparing non-CSCs to CSCs, and focused on miRs that target translation and protein synthesis factors. We describe a unique translation regulatory axis enacted by reduced expression of miR-183 in breast CSCs, which we show targets the eIF2Bδ subunit of guanine nucleotide exchange factor eIF2B, a regulator of protein synthesis and the integrated stress response (ISR) pathway. We report that reduced expression of miR-183 greatly increases eIF2Bδ protein levels, preventing strong induction of the ISR and eIF2α phosphorylation, by preferential interaction with P-eIF2α. eIF2Bδ overexpression is essential for BC cell invasion, metastasis, maintenance of metastases, and breast CSC expansion in animal models. Increased expression of eIF2Bδ, a site of action of the drug ISRIB that also prevents ISR signaling, is essential for breast CSC maintenance and metastatic capacity.
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Zaersabet M, Koochakkhani S, Sarmast Y, Salmani H. Homozygosity for a novel DOCK6 variant in an individual without aplasia cutis congenita of the scalp and terminal transverse limb defects. Clin Dysmorphol 2023; 32:84-87. [PMID: 36779775 DOI: 10.1097/mcd.0000000000000450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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Sacco KA, Notarangelo LD, Delmonte OM. When to suspect inborn errors of immunity in Epstein-Barr virus-related lymphoproliferative disorders. Clin Microbiol Infect 2023; 29:457-462. [PMID: 36209991 PMCID: PMC10066820 DOI: 10.1016/j.cmi.2022.10.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 09/20/2022] [Accepted: 10/01/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND More than 95% of humans have been infected with Epstein-Barr virus (EBV) and develop anti-EBV IgG antibodies, conferring immunity. However, among specific populations, EBV may induce a range of B-cell lymphoproliferative disorders (LPDs). EBV may also contribute to T-cell and natural killer (NK)-cell lymphoproliferation. The immune system is essential to prevent infection and development of cancer. Inborn errors of immunity (IEIs) are a heterogenous group of more than 450 genetic disorders predisposing to severe and/or recurrent infection, autoimmunity, autoinflammation, or early-onset/severe neoplasia or lymphoproliferation. Monogenic disorders of T-cell and B-cell signalling are classic IEIs that predispose to EBV-associated LPDs. OBJECTIVES We aimed to outline the various clinical manifestations of EBV-associated LPDs and the underlying IEIs associated with such presentations and discuss the recommended management and therapeutic options pertaining to these disorders. SOURCES We searched PubMed, Embase, and Web of Science Core Collection on 30 September 2021. Clinical studies, systematic reviews, narrative reviews, and case reports were identified through search strategy and cross reference from primary literature. CONTENT Effective T-cell and NK-cell cytotoxicity towards EBV-infected B cells relies on intact MAGT1-dependent NKG2D pathways and signalling lymphocyte activation molecular-associated protein-dependent signalling lymphocyte activation molecular receptors. The interaction between CD27 and CD70 is also critical to drive the expansion of EBV-specific T cells. IEIs due to T-cell and B-cell signalling defects and/or impaired T-cell and NK-cell cytotoxicity predispose to EBV-related lymphoproliferation. This includes classic disorders such as X-linked lymphoproliferative disease 1 (due to SH2D1A mutations), X-linked lymphoproliferative disease 2 (XIAP), and other genetic diseases, such as ITK, MAGT1, CD27, CD70, CTPS1, RASGRP1, and CORO1A deficiencies. EBV-driven lymphoproliferation may manifest to a lesser degree in MST1/STK4, DOCK8, STIM1, CORO1A, IL21R, PIK3CD gain-of-function, and PI3KR1 deficiencies. IMPLICATIONS Early screening for IEIs is indicated in cases of EBV-related lymphoproliferation because different forms of IEIs have specific prognostic and therapeutic implications.
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Morino K, Kunimura K, Sugiura Y, Izumi Y, Matsubara K, Akiyoshi S, Maeda R, Hirotani K, Sakata D, Mizuno S, Takahashi S, Bamba T, Uruno T, Fukui Y. Cholesterol sulfate limits neutrophil recruitment and gut inflammation during mucosal injury. Front Immunol 2023; 14:1131146. [PMID: 37006281 PMCID: PMC10063914 DOI: 10.3389/fimmu.2023.1131146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 03/09/2023] [Indexed: 03/19/2023] Open
Abstract
During mucosal injury, intestinal immune cells play a crucial role in eliminating invading bacteria. However, as the excessive accumulation of immune cells promotes inflammation and delays tissue repair, it is essential to identify the mechanism that limits the infiltration of immune cells to the mucosal-luminal interface. Cholesterol sulfate (CS) is the lipid product of the sulfotransferase SULT2B1 and suppresses immune reactions by inhibiting DOCK2-mediated Rac activation. In this study, we aimed to elucidate the physiological role of CS in the intestinal tract. We found that, in the small intestine and colon, CS is predominantly produced in the epithelial cells close to the lumen. While dextran sodium sulfate (DSS)-induced colitis was exacerbated in Sult2b1-deficient mice with increased prevalence of neutrophils, the elimination of either neutrophils or intestinal bacteria in Sult2b1-deficient mice attenuated disease development. Similar results were obtained when the Dock2 was genetically deleted in Sult2b1-deficient mice. In addition, we also show that indomethacin-induced ulcer formation in the small intestine was exacerbated in Sult2b1-deficient mice and was ameliorated by CS administration. Thus, our results uncover that CS acts on inflammatory neutrophils, and prevents excessive gut inflammation by inhibiting the Rac activator DOCK2. The administration of CS may be a novel therapeutic strategy for inflammatory bowel disease and non-steroidal anti-inflammatory drug-induced ulcers.
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Yagi H, Onoyama I, Asanoma K, Kawakami M, Maenohara S, Kodama K, Matsumura Y, Hamada N, Hori E, Hachisuga K, Yasunaga M, Ohgami T, Okugawa K, Yahata H, Kato K. Tumor-derived ARHGAP35 mutations enhance the Gα 13-Rho signaling axis in human endometrial cancer. Cancer Gene Ther 2023; 30:313-323. [PMID: 36257976 DOI: 10.1038/s41417-022-00547-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 09/26/2022] [Accepted: 10/06/2022] [Indexed: 11/08/2022]
Abstract
Dysregulated G protein-coupled receptor signaling is involved in the formation and progression of human cancers. The heterotrimeric G protein Gα13 is highly expressed in various cancers and regulates diverse cancer-related transcriptional networks and cellular functions by activating Rho. Herein, we demonstrate that increased expression of Gα13 promotes cell proliferation through activation of Rho and the transcription factor AP-1 in human endometrial cancer. Of interest, the RhoGTPase activating protein (RhoGAP), ARHGAP35 is frequently mutated in human endometrial cancers. Among the 509 endometrial cancer samples in The Cancer Genome Atlas database, 108 harbor 152 mutations at 126 different positions within ARHGAP35, representing a somatic mutation frequency of 20.2%. We evaluated the effect of 124 tumor-derived ARHGAP35 mutations on Gα13-mediated Rho and AP-1 activation. The RhoGAP activity of ARHGAP35 was impaired by 55 of 124 tumor-derived mutations, comprised of 23 nonsense, 15 frame-shift, 15 missense mutations, and two in-frame deletions. Considering that ARHGAP35 is mutated in >2% of all tumors, it ranks among the top 30 most significantly mutated genes in human cancer. Our data suggest potential roles of ARHGAP35 as an oncogenic driver gene, providing novel therapeutic opportunities for endometrial cancer.
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Low JY, Ko M, Hanratty B, Patel RA, Bhamidipati A, Heaphy CM, Sayar E, Lee JK, Li S, De Marzo AM, Nelson WG, Gupta A, Yegnasubramanian S, Ha G, Epstein JI, Haffner MC. Genomic Characterization of Prostatic Basal Cell Carcinoma. THE AMERICAN JOURNAL OF PATHOLOGY 2023; 193:4-10. [PMID: 36309102 PMCID: PMC9768679 DOI: 10.1016/j.ajpath.2022.09.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/13/2022] [Accepted: 09/30/2022] [Indexed: 11/05/2022]
Abstract
Basal cell carcinoma (BCC) of the prostate is a rare tumor. Compared with the more common acinar adenocarcinoma (AAC) of the prostate, BCCs show features of basal cell differentiation and are thought to be biologically distinct from AAC. The spectrum of molecular alterations of BCC has not been comprehensively described, and genomic studies are lacking. Herein, whole genome sequencing was performed on archival formalin-fixed, paraffin-embedded specimens of two cases with BCC. Prostatic BCCs were characterized by an overall low copy number and mutational burden. Recurrent copy number loss of chromosome 16 was observed. In addition, putative driver gene alterations in KIT, DENND3, PTPRU, MGA, and CYLD were identified. Mechanistically, depletion of the CYLD protein resulted in increased proliferation of prostatic basal cells in vitro. Collectively, these studies show that prostatic BCC displays distinct genomic alterations from AAC and highlight a potential role for loss of chromosome 16 in the pathogenesis of this rare tumor type.
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Miyazaki S, Takino JI, Nagamine K, Hori T. RasGRP2 Attenuates Oxygen Deprivation-Induced Autophagy in Vascular Endothelial Cells. Biol Pharm Bull 2023; 46:1512-1516. [PMID: 37914354 DOI: 10.1248/bpb.b23-00317] [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] [Indexed: 11/03/2023]
Abstract
Vascular endothelial cells sustain vascular health through barrier and endocrine functions. Insufficient oxygen supply induces endothelial dysfunction in the pathology of various diseases. In addition, oxygen deprivation reportedly induces endothelial dysfunction via autophagy. Ras guanyl-releasing protein 2 (RasGRP2) has guanosine 5'-diphosphate (GDP)/guanosine 5'-triphosphate (GTP) exchange factor activity and activates Rap1 and R-Ras which belong to the small GTPases. RasGRP2 exerts protective effects against vascular endothelial dysfunction. However, the effect of RasGRP2 on hypoxic stress in vascular endothelial cells has not yet been investigated. We examined the protein expression of hypoxia-inducible factor (HIF)-1α, BCL2 interacting protein 3 (BNIP3), and microtubule-associated protein light chain 3β (LC3β). We observed that oxygen deprivation increased the expression of HIF-1α, BNIP3 and LC3β II. RasGRP2 suppressed the induction of HIF-1α and the subsequent increase in LC3β II. These findings suggest the possibility that RasGRP2 plays a protective role against endothelial dysfunction by suppressing oxygen deprivation-induced autophagy.
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Wang DH, Niu XY, Cheng MM, Chen Y, Yang Y, Yang XL, Yang ZX, Zhang YH. [Genotypes and phenotypes of IQSEC2 gene variants related epilepsy]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2022; 60:1317-1321. [PMID: 36444437 DOI: 10.3760/cma.j.cn112140-20220614-00550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Objective: To analyze the genotypes and clinical phenotypes of patients with epilepsy associated with IQSEC2 gene variants. Methods: The genotypes, seizure types, electroencephalogram, neuroimage of 6 patients with IQSEC2 gene variants in the Department of Pediatrics, Peking University First Hospital from July 2019 to October 2021 were analyzed. Results: There were 5 males and 1 female. Six variants were de novo, including 2 frameshift variants (c.3801_3808dup/p.Q1270Rfs*130, c.1459_1460delAT/p.M487Vfs*2), 2 nonsense variants (c.3163C>T/p.R1055*, c.1417G>T/p.E473*), 1 in-frame deletion (c.2295_2297del/p.N765del) and 1 missense variant (c.2293A>G/p.N765D). Age at seizure onset ranged from 3 months to 2 years and 5 months. Multiple seizure types were observed, including epileptic spasms in 5 patients, focal seizures in 5 patients, tonic seizures in 3 patients, myoclonic seizures in 3 patients, atypical absence seizures in 2 patients and atonic seizures in 2 patients. All 6 patients showed global developmental delay before seizure onset. There were other clinical manifestations, including autistic features in 3 patients, microcephaly in 3 patients, dystonia in 2 patients and binocular esotropia in 1 patient. The electroencephalogram showed slow background activity and hypsarrhythmia in all 6 patients. Brain magnetic resonance imaging showed abnormal in 5 patients and normal in 1 patient. Five patients were diagnosed with infantile spasms. Among them, 4 patients had late-onset infantile spasms. One patient was unclassified developmental epileptic encephalopathy. The age of last follow-up ranged from 3 years and 2 months to 7 years and 2 months. All 6 patients still had seizures after multiple anti-seizure medications. Conclusions: The seizure onset of patients with IQSEC2 gene variants usually begins after 1 year of age. The common seizure types include epileptic spasms and focal seizures. Patients usually have a global developmental delay before seizure onset. IQSEC2 variants could be related to developmental and epileptic encephalopathy, and most patients are diagnosed with late onset infantile spasms. Epilepsy associated with IQSEC2 gene variants is usually refractory.
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Zheng C, Xu G, Tang D, Ni M, Cheng Y, Du M, Wang Y, Xu Y, Jiang J, Xiang Y, Sun Q, Chen L, Fan X, Huang Q, Zhou Y, Zou X, Wang L. A Retrospective Cohort Study of Factors Influencing Lymph Node Metastasis in Patients With Early Gastric Papillary Adenocarcinoma. Clin Transl Gastroenterol 2022; 13:e00519. [PMID: 36000982 PMCID: PMC9780111 DOI: 10.14309/ctg.0000000000000519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 07/25/2022] [Indexed: 01/31/2023] Open
Abstract
INTRODUCTION High risk of lymph node metastasis (LNM) in gastric papillary adenocarcinoma causes endoscopists to worry about the suitability of endoscopic resection for early gastric papillary adenocarcinoma (EPAC). We compared risk factors and attempted to establish a scoring system to stratify LNM risk in patients with EPAC. METHODS A retrospective analysis was performed on 2,513 patients with early gastric carcinoma (EGC) who underwent radical resection in 4 tertiary hospitals in China. Univariate and multivariate analyses were performed to compare the invasiveness in EPAC and other types of EGC and to evaluate potential factors in predicting LNM risk in EPAC groups. RESULTS Three hundred thirty-five patients with EPAC were enrolled in our study, of which 62 patients were found to have LNM. After comparing clinicopathological characteristics of EPAC with and without LNM, the following factors were included in the risk scoring system: 1 point each for lower stomach location and tumor size >2.0 cm, 3 points for lymphovascular invasion, and 4 points for submucosal invasion; the risk scoring system was validated in a small internal validation set with an area under the curve of 0.844. DISCUSSION Our results suggested that EPAC was highly invasive compared with other EGCs, especially differentiated EGC types, and need to be treated more rigorously. This proposed risk scoring system could stratify LNM risk in patients with EPAC, and endoscopic resection may only be performed safely on the groups with a low LNM rate.
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Lippincott MF, Xu W, Smith AA, Miao X, Lafont A, Shennib O, Farley GJ, Sabbagh R, Delaney A, Stamou M, Plummer L, Salnikov K, Georgopoulos NA, Mericq V, Quinton R, Mau-Them FT, Nambot S, Hamad A, Brittain H, Tooze RS, Calpena E, Wilkie AOM, Willems M, Crowley WF, Balasubramanian R, Lamarche-Vane N, Davis EE, Seminara SB. The p190 RhoGAPs, ARHGAP35, and ARHGAP5 are implicated in GnRH neuronal development: Evidence from patients with idiopathic hypogonadotropic hypogonadism, zebrafish, and in vitro GAP activity assay. Genet Med 2022; 24:2501-2515. [PMID: 36178483 PMCID: PMC9730938 DOI: 10.1016/j.gim.2022.08.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/24/2022] [Accepted: 08/24/2022] [Indexed: 12/14/2022] Open
Abstract
PURPOSE The study aimed to identify novel genes for idiopathic hypogonadotropic hypogonadism (IHH). METHODS A cohort of 1387 probands with IHH underwent exome sequencing and de novo, familial, and cohort-wide investigations. Functional studies were performed on 2 p190 Rho GTPase-activating proteins (p190 RhoGAP), ARHGAP35 and ARHGAP5, which involved in vivo modeling in larval zebrafish and an in vitro p190A-GAP activity assay. RESULTS Rare protein-truncating variants (PTVs; n = 5) and missense variants in the RhoGAP domain (n = 7) in ARHGAP35 were identified in IHH cases (rare variant enrichment: PTV [unadjusted P = 3.1E-06] and missense [adjusted P = 4.9E-03] vs controls). Zebrafish modeling using gnrh3:egfp phenotype assessment showed that mutant larvae with deficient arhgap35a, the predominant ARHGAP35 paralog in the zebrafish brain, display decreased GnRH3-GFP+ neuronal area, a readout for IHH. In vitro GAP activity studies showed that 1 rare missense variant [ARHGAP35 p.(Arg1284Trp)] had decreased GAP activity. Rare PTVs (n = 2) also were discovered in ARHGAP5, a paralog of ARHGAP35; however, arhgap5 zebrafish mutants did not display significant GnRH3-GFP+ abnormalities. CONCLUSION This study identified ARHGAP35 as a new autosomal dominant genetic driver for IHH and ARHGAP5 as a candidate gene for IHH. These observations suggest a novel role for the p190 RhoGAP proteins in GnRH neuronal development and integrity.
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Hernández C, Gómez-Peralta F, Simó-Servat O, García-Ramírez M, Abreu C, Gómez-Rodríguez S, Simó R. Usefulness of circulating EPAC1 as biomarkers of therapeutic response to GLP-1 receptor agonists. Acta Diabetol 2022; 59:1437-1442. [PMID: 35925404 DOI: 10.1007/s00592-022-01928-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 06/22/2022] [Indexed: 11/30/2022]
Abstract
AIMS The response to Glucagon-like peptide-1 receptor agonists (GLP-1RAs) is highly varia-ble among patients. Thus, the identification of predictive biomarkers of therapeutic response to GLP-1 RA could help us to optimize the use of this class of drugs. GLP-1RAs increase exchange proteins directly activated by cAMP (EPAC). The aim of the present study was to assess whether the increase of EPAC1 after GLP-1RAs treatment could be a biomarker of clinical response. METHODS After showing that GLP-1 (10 ng/mL) significantly increased the expression of EPAC1 in human endo-thelial vascular cells (HUVEC), a pilot clinical study was planned. For this purpose 49 patients with type 2 diabetes who started treatment with liraglutide were included. EPAC1 concentration was determined by ELISA before and at one month of liraglutide treatment. RESULTS We found that serum concentration of EPAC1 increased significantly after treatment with liraglutide. Only in those patients in whom EPAC1 increased (64%), a significant decrease in HbA1c, LDL-C, body mass index (BMI), and waist circumference was shown. CONCLUSIONS This pilot study suggests that the increase of circulating EPAC1 after GLP-1RAs treatment could be a useful biomarker to predict clinical GLP1-RAs response.
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Gelzo M, Castaldo A, Giannattasio A, Scalia G, Raia M, Esposito MV, Maglione M, Muzzica S, D’Anna C, Grieco M, Tipo V, La Cava A, Castaldo G. MIS-C: A COVID-19-as sociated condition between hypoimmunity and hyperimmunity. Front Immunol 2022; 13:985433. [PMID: 36263058 PMCID: PMC9574022 DOI: 10.3389/fimmu.2022.985433] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Accepted: 09/15/2022] [Indexed: 11/13/2022] Open
Abstract
Multisystem inflammatory syndrome in children (MIS-C) is a rare, severe complication of COVID-19. A better knowledge of immunological, cellular, and genetic characteristics of MIS-C could help better understand the pathogenesis of the disease and contribute to identifying specific diagnostic biomarkers and develop targeted therapies. We studied 37 MIS-C children at hospital admission and 24 healthy controls analyzing serum cytokines (IFN-α, IFN-β, IFN-γ, IL-6, IL-10, IL-17A, IL-12p70 and TNF), lymphocyte populations by flow cytometry and 386 genes related to autoimmune diseases, autoinflammation and primary immunodeficiencies by NGS. MIS-C patients showed a significant increase of serum IFNγ (despite a significant reduction of activated Th1) and ILs, even if with a great heterogeneity among patients, revealing different pathways involved in MIS-C pathogenesis and suggesting that serum cytokines at admission may help to select the inflammatory pathways to target in each patient. Flow cytometry demonstrated a relevant reduction of T populations while the percentage of B cell was increased in agreement with an autoimmune pathogenesis of MIS-C. Genetic analysis identified variants in 34 genes and 83.3% of patients had at least one gene variant. Among these, 9 were mutated in more patients. Most genes are related to autoimmune diseases like ATM, NCF1, MCM4, FCN3, and DOCK8 or to autoinflammatory diseases associated to the release of IFNγ like PRF1, NOD2, and MEF. Thus, an incomplete clearance of the Sars-CoV2 during the acute phase may induce tissue damage and self-antigen exposure and genetic variants can predispose to hyper-reactive immune dysregulation events of MIS-C-syndrome. Type II IFN activation and cytokine responses (mainly IL-6 and IL-10) may cause a cytokine storm in some patients with a more severe acute phase of the disease, lymphopenia and multisystemic organ involvement. The timely identification of such patients with an immunocytometric panel might be critical for targeted therapeutic management.
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Xu L, Zhang X, Zheng D, Chang Y, Zhang F, Wang Y, Huang L. VmMon1-Ccz1 Complex Is Required for Conidiation, Autophagy, and Virulence in Valsa mali. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:906-916. [PMID: 35793146 DOI: 10.1094/mpmi-03-22-0071-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Apple Valsa canker caused by Valsa mali is a serious disease in eastern Asia, especially in China. In our previous proteomics study, monensin sensitivity 1 protein in Valsa mali (VmMon1) was identified to be significantly upregulated during V. mali infection. It was reported Mon1 protein formed a heterodimer called MC (Mon1-Ccz1) complex with caffeine, calcium, and zinc sensitivity 1 protein (Ccz1) in yeast. However, Ccz1 had not been identified in plant-pathogenic fungi such as Fusarium graminearum and Magnaporthe oryzae. Here, we identified a Ccz1 ortholog VmCcz1 in V. mali, by using DELTA-BLAST. The interaction of VmMon1 and VmCcz1 were verified using yeast two-hybrid assay, bimolecular fluorescence complementation, and co-immunoprecipitation assays. Further yeast three-hybrid screenings determined that VmRab7 (Ras-related protein in V. mali) interacted with the MC complex. Targeted gene deletion showed that the ∆VmMon1 and ∆VmCcz1 mutants were defective in vegetative growth, conidiation, and pathogenicity. In addition, both mutants were more sensitive to osmotic and oxidative stresses and intracellular protein transport inhibitors. Cytological examination revealed that the ∆VmMon1 and ∆VmCcz1 mutants were impaired in vacuole fusion and autophagy. More importantly, expression of pectinase genes decreased in both mutants compared with those of the wild type during infection. Overall, our study identified Mon1 and Ccz1 genes in V. mali and provided evidence that VmMon1 and VmCcz1 are critical components that modulate vacuole fusion and autophagy, thereby affecting the development, conidiation, and pathogenicity of V. mali. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Mašić M, Hojsak I, Niseteo T, Pustišek N, Jadrešin O, Ivković-Jureković I, Navratil M. Severe Protein Loss in a 6-month-old Exclusively Breastfed Infant with Atopic Dermatitis. ACTA DERMATOVENEROLOGICA CROATICA : ADC 2022; 30:106-109. [PMID: 36254543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Protein loss is often the result of kidney or intestinal disease (protein-losing enteropathy) and can cause a number of serious, potentially life-threatening complications such as hypotension, thrombocytosis, electrolyte imbalance, and cerebellar ischemia. Recent research suggests an association between extremely severe atopic dermatitis (AD) and allergic enteropathy. An exclusively breastfed 6-month-old infant was admitted to our institution due to failure to thrive, electrolyte imbalance, and severe AD (SCORing Atopic Dermatitis; SCORAD 40). On admission, the infant was in poor general condition, dehydrated, malnourished (bodyweight 4870 g, -3.98 z-score), with exudative erythematous morphs scattered throughout the body. Initial laboratory results showed microcytic hypochromic anemia, hypoalbuminemia, hypogammaglobinemia, thrombocytosis, hyponatremia, high values of total immunoglobulin E (IgE), and eosinophilia. Polysensitization to a number of nutritional and inhalation allergens was demonstrated, and an exclusive amino acid-based formula has been introduced into the diet. During the hospital course, the patient developed superficial thrombophlebitis and methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Eosinophilia was found in a small intestine biopsy sample. Due to severe hypogammaglobulinemia, skin infections, and bacteremia, the differential diagnosis included primary immune deficiency (STAT3 deficiency, DOCK8 deficiency, PGM3 deficiency, IPEX), but all available immunological tests were unremarkable. Exclusive amino acid-based formula diet was continued in the infant, with topical corticosteroids under wet-dressing therapy and intravenous immunoglobulin replacement therapy. With the gradual improvement of the general condition, the introduction of solid foods was started according to the findings of allergy testing. At 17 months of age, the patient gained weight and his skin status has been improving, although frequent use of topical corticosteroids was necessary. There were no infections, no anemia or thrombocytosis, and albumin and immunoglobulin supplementation were no longer required. The main mechanism of protein loss in infants with extremely severe atopic dermatitis is probably due to damaged skin, and partially due to the eosinophilic inflammation of the small intestine. Immunoglobulin loss, potentiated by physiological or transient hypogammaglobulinemia in infants, poses a very high risk for severe, potentially life-threatening infections.
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Gupta S, Vundavilli H, Osorio RSA, Itoh MN, Mohsen A, Datta A, Mizuguchi K, Tripathi LP. Integrative Network Modeling Highlights the Crucial Roles of Rho-GDI Signaling Pathway in the Progression of Non-Small Cell Lung Cancer. IEEE J Biomed Health Inform 2022; 26:4785-4793. [PMID: 35820010 DOI: 10.1109/jbhi.2022.3190038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Non-small cell lung cancer (NSCLC) is the most prevalent form of lung cancer and a leading cause of cancer-related deaths worldwide. Using an integrative approach, we analyzed a publicly available merged NSCLC transcriptome dataset using machine learning, protein-protein interaction (PPI) networks and bayesian modeling to pinpoint key cellular factors and pathways likely to be involved with the onset and progression of NSCLC. First, we generated multiple prediction models using various machine learning classifiers to classify NSCLC and healthy cohorts. Our models achieved prediction accuracies ranging from 0.83 to 1.0, with XGBoost emerging as the best performer. Next, using functional enrichment analysis (and gene co-expression network analysis with WGCNA) of the machine learning feature-selected genes, we determined that genes involved in Rho GTPase signaling that modulate actin stability and cytoskeleton were likely to be crucial in NSCLC. We further assembled a PPI network for the feature-selected genes that was partitioned using Markov clustering to detect protein complexes functionally relevant to NSCLC. Finally, we modeled the perturbations in RhoGDI signaling using a bayesian network; our simulations suggest that aberrations in ARHGEF19 and/or RAC2 gene activities contributed to impaired MAPK signaling and disrupted actin and cytoskeleton organization and were arguably key contributors to the onset of tumorigenesis in NSCLC. We hypothesize that targeted measures to restore aberrant ARHGEF19 and/or RAC2 functions could conceivably rescue the cancerous phenotype in NSCLC. Our findings offer promising avenues for early predictive biomarker discovery, targeted therapeutic intervention and improved clinical outcomes in NSCLC.
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Sullivan NT, Cooke M. Protocol for fluorescence-activated cell sorting of human EpCAM + lung cancer cells for gene expression analysis of Rac guanine-nucleotide exchange factors. STAR Protoc 2022; 3:101367. [PMID: 35542175 PMCID: PMC9079335 DOI: 10.1016/j.xpro.2022.101367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Here, we describe a protocol for fluorescence-activated cell sorting (FACS) of human EpCAM+ cells from fresh surgically resected specimens. We then use Q-PCR to identify specific molecular targets associated with the metastatic phenotype. This combined approach enables a qualitative and quantitative gene expression analysis of lung cancer samples. We describe how to use the protocol for Rac GEFs, but it can be applied broadly to other molecular targets. For complete details on the use and execution of this protocol, please refer to Cooke et al. (2021) and Quatromoni et al. (2015).
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Durkee-Shock J, Zhang A, Liang H, Wright H, Magnusson J, Garabedian E, Marsh RA, Sullivan KE, Keller MD. Morbidity, Mortality, and Therapeutics in Combined Immunodeficiency: Data From the USIDNET Registry. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY. IN PRACTICE 2022; 10:1334-1341.e6. [PMID: 35172220 DOI: 10.1016/j.jaip.2022.01.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/05/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Optimal management of patients with combined immunodeficiency, especially pertaining to hematopoietic stem cell transplantation (HSCT), remains unclear. OBJECTIVE To identify factors influencing HSCT and mortality in the population with combined immunodeficiency in North America. METHODS We identified 337 participants in the United States Immunodeficiency Network database with diverse forms of combined immunodeficiency and their characteristics, including demographic characteristics, laboratory values, infectious history, comorbidities, and treatment strategies. Univariate analysis was performed using logistic regression, whereas multivariate analysis was performed using multiple Cox proportional hazards. RESULTS On univariate analysis, disseminated invasive viral infections and variants in STAT3, GATA2, and, DOCK8 were associated with increased odds of HSCT. Mucocutaneous fungal infections and variants in STAT3 were associated with increased odds of survival, whereas disseminated/invasive fungal infections, disseminated/invasive viral infections, and parasitic infections were associated with decreased odds of survival. On multiple variable Cox proportional hazards analysis, variants in ZAP70, nonspecific bacterial, and disseminated/invasive viral infections were associated with increased hazards of transplantation, whereas variants in multiple genes (RMRP, NEMO, DOCK8, CD40L, and CARD9), disseminated/invasive viral infections, autoimmune disease, and higher absolute lymphocyte count were associated with increased hazards of death. Importantly, demographic characteristics, basic lymphocyte subset counts, and absence of genetic diagnosis were not associated with HSCT or mortality. CONCLUSIONS We determined that specific genetic diagnoses and infection burden impacts the decision to undergo HSCT in this cohort. In addition, certain genetic diagnoses and invasive viral infections carry an increased risk of mortality.
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Purzycka-Bohdan D, Nowicki RJ, Herms F, Casanova JL, Fouéré S, Béziat V. The Pathogenesis of Giant Condyloma Acuminatum (Buschke-Lowenstein Tumor): An Overview. Int J Mol Sci 2022; 23:4547. [PMID: 35562936 PMCID: PMC9100137 DOI: 10.3390/ijms23094547] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/13/2022] [Accepted: 04/18/2022] [Indexed: 11/18/2022] Open
Abstract
Giant condyloma acuminatum, also known as Buschke-Lowenstein tumor (BLT), is a rare disease of the anogenital region. BLT is considered a locally aggressive tumor of benign histological appearance, but with the potential for destructive growth and high recurrence rates. BLT development is strongly associated with infection with low-risk human papillomaviruses (HPVs), mostly HPV-6 and -11. Immunity to HPVs plays a crucial role in the natural control of various HPV-induced lesions. Large condyloma acuminata are frequently reported in patients with primary (e.g., DOCK8 or SPINK5 deficiencies) and secondary (e.g., AIDS, solid organ transplantation) immune defects. Individuals with extensive anogenital warts, including BLT in particular, should therefore be tested for inherited or acquired immunodeficiency. Research into the genetic basis of unexplained cases is warranted. An understanding of the etiology of BLT would lead to improvements in its management. This review focuses on the role of underlying HPV infections, and human genetic and immunological determinants of BLT.
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Liu Y, Tang W, Ao J, Zhang J, Feng L. Transcriptomics integrated with metabolomics reveals the effect of Bisphenol F (BPF) exposure on intestinal inflammation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 816:151644. [PMID: 34774955 DOI: 10.1016/j.scitotenv.2021.151644] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 10/16/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
As a viable alternative to Bisphenol A (BPA), Bisphenol F (BPF) has been detected in humans at comparable concentrations and detection frequencies. Emerging evidence reveals that BPF induces intestinal toxicity. However, less information is available concerning BPF and its potential effects on intestinal inflammation, which has been associated with numerous disorders. The results from the present study showed that BPF exposure triggered lipopolysaccharide (LPS)-induced explosion of pro-inflammatory cytokines interleukin-17A (IL-17A), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) and impairment of the intestinal epithelial barrier by downregulating the expression of tight junction proteins Zonula Occludens-1 (ZO-1) and Claudin-1 (CLDN1) in normal colonic epithelial cells (NCM460). A multi-omics analysis integrating the transcriptomics with metabolomics revealed an altered transcripts and metabolites profile following BPF exposure. Correlation analysis indicated that RAS Guanyl Releasing Protein 2 (RASGRP2) and Phospholipase A2 Group IVE (PLA2G4E) were positively associated with the increased serotonin which was positively associated with the stimulated IFN-γ in BPF-treated NCM460 cells. Pyrogallol, pyridoxine, and N-acetylputrescine were positively associated with IL-17A levels. Collectively, the integrative analyses demonstrated an orchestrated coordination between the inflammatory response, transcriptomic, and metabolomics changes. Data presented herein provide evidence for the possible roles of BPF in the pathogenesis of intestinal inflammation. These results illustrate the advantages of using integrative analyses of high throughput datasets for characterizing the effects and mechanisms of toxicants.
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Pavanelli AC, Mangone FR, Yoganathan P, Bessa SA, Nonogaki S, de Toledo Osório CAB, de Andrade VP, Soares IC, de Mello ES, Mulligan LM, Nagai MA. Comprehensive immunohistochemical analysis of RET, BCAR1, and BCAR3 expression in patients with Luminal A and B breast cancer subtypes. Breast Cancer Res Treat 2022; 192:43-52. [PMID: 35031902 DOI: 10.1007/s10549-021-06452-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/14/2021] [Indexed: 12/19/2022]
Abstract
PURPOSE Breast cancer (BC) is considered a heterogeneous disease composed of distinct subtypes with diverse clinical outcomes. Luminal subtype tumors have the best prognosis, and patients benefit from endocrine therapy. However, resistance to endocrine therapies in BC is an obstacle to successful treatment, and novel biomarkers are needed to understand and overcome this mechanism. The RET, BCAR1, and BCAR3 genes may be associated with BC progression and endocrine resistance. METHODS Aiming to evaluate the expression profile and prognostic value of RET, BCAR1, and BCAR3, we performed immunohistochemistry on tissue microarrays (TMAs) containing a cohort of 361 Luminal subtype BC. RESULTS Low expression levels of these three proteins were predominantly observed. BCAR1 expression was correlated with nuclear grade (p = 0.057), and BCAR3 expression was correlated with lymph node status (p = 0.011) and response to hormonal therapy (p = 0.021). Further, low expression of either BCAR1 or BCAR3 was significantly associated with poor prognosis (p = 0.005; p = 0.042). Pairwise analysis showed that patients with tumors with low BCAR1/low BCAR3 expression had a poorer overall survival (p = 0.013), and the low BCAR3 expression had the worst prognosis with RET high expression stratifying these patients into two different groups. Regarding the response to hormonal therapy, non-responder patients presented lower expression of RET in comparison to the responder group (p = 0.035). Additionally, the low BCAR1 expression patients had poorer outcomes than BCAR1 high (p = 0.015). CONCLUSION Our findings suggest RET, BCAR1, and BCAR3 as potential candidate markers for endocrine therapy resistance in Luminal BC.
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Abstract
Primary ovarian insufficiency (POI) is determined by exhaustion of follicles in the ovaries, which leads to infertility before the age of 40 years. It is characterized by a strong familial and heterogeneous genetic background. Therefore, we will mainly discuss the genetic basis of POI in this review. We identified 107 genes related to POI etiology in mammals described by several independent groups. Thirty-four of these genes (AARS2, AIRE, ANTXR1, ATM, BMPR1B, CLPP, CYP17A1, CYP19A1, DCAF17, EIF2B, ERAL1, FANCA, FANCC, FMR1, FOXL2, GALT, GNAS, HARS2, HSD17B4, LARS2, LMNA, MGME1, NBN, PMM2, POLG, PREPL, RCBTB1, RECQL2/3/4, STAR, TWNK, and XRCC4/9) have been linked to syndromic POI and are mainly implicated in metabolism function and meiosis/DNA repair. In addition, the majority of genes associated with nonsyndromic POI, widely expanded by high-throughput techniques over the last decade, have been implicated in ovarian development and meiosis/DNA repair pathways (ATG7, ATG9, ANKRD31, BMP8B, BMP15, BMPR1A, BMPR1B, BMPR2, BNC1, BRCA2, CPEB1, C14ORF39, DAZL, DIAPH2, DMC1, ERCC6, FANCL, FANCM, FIGLA, FSHR, GATA4, GDF9, GJA4, HELQ, HSF2BP, HFM1, INSL3, LHCGR, LHX8, MCM8, MCM9, MEIOB, MSH4, MSH5, NANOS3, NOBOX, NOTCH2, NR5A1, NUP107, PGRMC1, POLR3H, PRDM1, PRDM9, PSMC3IP, SOHLH1, SOHLH2, SPIDR, STAG3, SYCE1, TP63, UBR2, WDR62, and XRCC2), whereas a few are related to metabolic functions (EIF4ENIF1, KHDRBS1, MRPS22, POLR2C). Some genes, such as STRA8, FOXO3A, KIT, KITL, WNT4, and FANCE, have been shown to cause ovarian insufficiency in rodents, but mutations in these genes have yet to be elucidated in women affected by POI. Lastly, some genes have been rarely implicated in its etiology (AMH, AMHR2, ERRC2, ESR1, INHA, LMN4, POF1B, POU5F1, REC8, SMC1B). Considering the heterogeneous genetic and familial background of this disorder, we hope that an overview of literature data would reinforce that genetic screening of those patients is worthwhile and helpful for better genetic counseling and patient management.
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Escrevente C, Bento-Lopes L, Ramalho JS, Barral DC. Rab11 is required for lysosome exocytosis through the interaction with Rab3a, Sec15 and GRAB. J Cell Sci 2021; 134:jcs246694. [PMID: 34100549 PMCID: PMC8214760 DOI: 10.1242/jcs.246694] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 04/26/2021] [Indexed: 12/19/2022] Open
Abstract
Lysosomes are dynamic organelles, capable of undergoing exocytosis. This process is crucial for several cellular functions, namely plasma membrane repair. Nevertheless, the molecular machinery involved in this process is poorly understood. Here, we identify Rab11a and Rab11b as regulators of Ca2+-induced lysosome exocytosis. Interestingly, Rab11-positive vesicles transiently interact with lysosomes at the cell periphery, indicating that this interaction is required for the last steps of lysosome exocytosis. Additionally, we found that the silencing of the exocyst subunit Sec15, a Rab11 effector, impairs lysosome exocytosis, suggesting that Sec15 acts together with Rab11 in the regulation of lysosome exocytosis. Furthermore, we show that Rab11 binds the guanine nucleotide exchange factor for Rab3a (GRAB) as well as Rab3a, which we have previously described to be a regulator of the positioning and exocytosis of lysosomes. Thus, our study identifies new players required for lysosome exocytosis and suggest the existence of a Rab11-Rab3a cascade involved in this process.
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Montenont E, Bhatlekar S, Jacob S, Kosaka Y, Manne BK, Lee O, Parra-Izquierdo I, Tugolukova E, Tolley ND, Rondina MT, Bray PF, Rowley JW. CRISPR-edited megakaryocytes for rapid screening of platelet gene functions. Blood Adv 2021; 5:2362-2374. [PMID: 33944898 PMCID: PMC8114553 DOI: 10.1182/bloodadvances.2020004112] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 03/09/2021] [Indexed: 01/07/2023] Open
Abstract
Human anucleate platelets cannot be directly modified using traditional genetic approaches. Instead, studies of platelet gene function depend on alternative models. Megakaryocytes (the nucleated precursor to platelets) are the nearest cell to platelets in origin, structure, and function. However, achieving consistent genetic modifications in primary megakaryocytes has been challenging, and the functional effects of induced gene deletions on human megakaryocytes for even well-characterized platelet genes (eg, ITGA2B) are unknown. Here we present a rapid and systematic approach to screen genes for platelet functions in CD34+ cell-derived megakaryocytes called CRIMSON (CRISPR-edited megakaryocytes for rapid screening of platelet gene functions). By using CRISPR/Cas9, we achieved efficient nonviral gene editing of a panel of platelet genes in megakaryocytes without compromising megakaryopoiesis. Gene editing induced loss of protein in up to 95% of cells for platelet function genes GP6, RASGRP2, and ITGA2B; for the immune receptor component B2M; and for COMMD7, which was previously associated with cardiovascular disease and platelet function. Gene deletions affected several select responses to platelet agonists in megakaryocytes in a manner largely consistent with those expected for platelets. Deletion of B2M did not significantly affect platelet-like responses, whereas deletion of ITGA2B abolished agonist-induced integrin activation and spreading on fibrinogen without affecting the translocation of P-selectin. Deletion of GP6 abrogated responses to collagen receptor agonists but not thrombin. Deletion of RASGRP2 impaired functional responses to adenosine 5'-diphosphate (ADP), thrombin, and collagen receptor agonists. Deletion of COMMD7 significantly impaired multiple responses to platelet agonists. Together, our data recommend CRIMSON for rapid evaluation of platelet gene phenotype associations.
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