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1.
Front Immunol ; 15: 1326370, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566993

RESUMO

Background: While a few case-control studies indicated a possible correlation of IgG N-glycosylation patterns with pancreatitis, their restricted sample sizes and methodologies prevented conclusive insights into causality or distinguishing traits across pancreatitis types. Method: We conducted a two-sample Mendelian Randomization (MR) analysis to investigate the causal relationship between 77 IgG N-glycosylation traits and various types of pancreatitis, including acute pancreatitis (AP), chronic pancreatitis (CP), alcohol acute pancreatitis (AAP), and alcohol chronic pancreatitis (ACP). This analysis utilized summary-level data from genome-wide association studies (GWAS), employing methods such as IVW, MR-Egger, and weighted median. To ensure the robustness of our findings, several sensitivity analyses, including Cochran's Q statistic, leave-one-out, MR-Egger intercept, and MR-PRESSO global test were conducted. Result: Our study uncovered the causal relationship between specific IgG N-glycosylation traits and various types of pancreatitis. Notably, an increase in genetically predicted IGP7 levels was associated with a decreased risk of developing AP. For CP, our data suggested a protective effect associated with higher levels of both IGP7 and IGP31, contrasting with increased levels of IGP27 and IGP65, which were linked to a heightened risk. Moreover, in the case of AAP, elevated IGP31 levels were causatively associated with a lower incidence, while higher IGP26 levels correlated with an increased risk for ACP. Conclusion: This study establishes causal relationship between specific IgG N-glycosylation patterns and varying risks of different pancreatitis forms, underscoring their potential as predictive biomarkers. These findings necessitate further exploration into the underlying mechanisms, promising to inform more personalized diagnostic and therapeutic strategies in pancreatitis management.


Assuntos
Imunoglobulina G , Pancreatite Crônica , Humanos , Doença Aguda , Etanol , Estudo de Associação Genômica Ampla , Glicosilação , Pancreatite Crônica/genética , Análise da Randomização Mendeliana
2.
Oncogene ; 43(20): 1506-1521, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38519641

RESUMO

Wnt/ß-catenin signalling is aberrantly activated in most colorectal cancer (CRC) and is one key driver involved in the initiation and progression of CRC. However, mutations of APC gene in CRC patients retain certain activity of APC protein with decreased ß-catenin signalling and DKK4 expression significantly upregulates and represses Wnt/ß-catenin signalling in human CRC tissues, suggesting that a precisely modulated activation of the Wnt/ß-catenin pathway is essential for CRC formation and progression. The underlying reasons why a specifically reduced degree, not a fully activating degree, of ß-catenin signalling in CRC are unclear. Here, we showed that a soluble extracellular inhibitor of Wnt/ß-catenin signalling, DKK4, is an independent factor for poor outcomes in CRC patients. DKK4 secreted from CRC cells inactivates ß-catenin in fibroblasts to induce the formation of stress fibre-containing fibroblasts and myofibroblasts in culture conditions and in mouse CRC xenograft tissues, resulting in restricted expansion in tumour masses at primary sites and enhanced CRC metastasis in mouse models. Reduced ß-catenin activity by a chemical inhibitor MSAB promoted the CRC metastasis. Our findings demonstrate why reduced ß-catenin activity is needed for CRC progression and provide a mechanism by which interactions between CRC cells and stromal cells affect disease promotion.


Assuntos
Neoplasias Colorretais , Peptídeos e Proteínas de Sinalização Intercelular , Metástase Neoplásica , Via de Sinalização Wnt , beta Catenina , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/genética , Humanos , Animais , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , beta Catenina/metabolismo , beta Catenina/genética , Fibroblastos/metabolismo , Fibroblastos/patologia , Linhagem Celular Tumoral , Masculino , Feminino , Camundongos Nus
3.
Exp Clin Endocrinol Diabetes ; 131(12): 676-685, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38056492

RESUMO

BACKGROUND: Clinical observation suggests the atheroprotective effect of chloroquine and its derivatives, while its mechanism remains unclear. This study aimed to observe the protective effect of chloroquine against atherosclerosis and explore the underlying mechanism. METHODS: Ataxia telangiectasia mutated (ATM) wild-type or haploinsufficient apolipoprotein-E-knockout (ATM+/+ApoE-/- or ATM+/-ApoE-/-) mice were treated with different dosages of chloroquine. Anti-CD25 antibody was used to deplete natural Tregs in ATM+/+ApoE-/- mice. The atherosclerotic burden in different groups of mice was comprehensively evaluated by H&E staining and Masson staining. The effect of chloroquine on the regulatory T cells (Tregs) was assessed in vivo and in vitro by flow cytometry and immunohistochemical staining. The expression of related proteins was detected by real-time polymerase chain reaction and western blotting. RESULTS: In ATM+/+ApoE-/- mice, chloroquine alleviated atherosclerotic lesions, stabilized the plaque, and increased Treg counts in the atherosclerotic lesions and spleens. However, in ATM haploinsufficient mice (ATM+/-ApoE-/-), chloroquine no longer prevented atherosclerosis or impacted Treg counts. Abolishing Treg cells using an anti-CD25 antibody in vivo abrogated the atheroprotective effect of chloroquine. In vitro, chloroquine promoted the differentiation of Tregs from naïve T cells, which was accompanied by enhanced ATM/AMP-activated protein kinase (AMPK) activity and reduced downstream mammalian target of rapamycin (mTOR) activity. DISCUSSION: These findings suggest that chloroquine ameliorates atherosclerosis and stabilizes plaque by modulating Tregs differentiation through the regulation of the ATM/AMPK/mTOR pathway.


Assuntos
Ataxia Telangiectasia , Aterosclerose , Placa Aterosclerótica , Camundongos , Animais , Linfócitos T Reguladores/metabolismo , Cloroquina/farmacologia , Cloroquina/metabolismo , Cloroquina/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Ataxia Telangiectasia/tratamento farmacológico , Ataxia Telangiectasia/metabolismo , Ataxia Telangiectasia/patologia , Camundongos Knockout para ApoE , Aterosclerose/tratamento farmacológico , Aterosclerose/prevenção & controle , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Apolipoproteínas E/metabolismo , Apolipoproteínas E/farmacologia , Apolipoproteínas E/uso terapêutico , Camundongos Endogâmicos C57BL , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patologia , Mamíferos/metabolismo
4.
J Clin Invest ; 133(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37815873

RESUMO

Many cancers harbor homologous recombination defects (HRDs). A HRD is a therapeutic target that is being successfully utilized in treatment of breast/ovarian cancer via synthetic lethality. However, canonical HRD caused by BRCAness mutations do not prevail in liver cancer. Here we report a subtype of HRD caused by the perturbation of a proteasome variant (CDW19S) in hepatitis B virus-bearing (HBV-bearing) cells. This amalgamate protein complex contained the 19S proteasome decorated with CRL4WDR70 ubiquitin ligase, and assembled at broken chromatin in a PSMD4Rpn10- and ATM-MDC1-RNF8-dependent manner. CDW19S promoted DNA end processing via segregated modules that promote nuclease activities of MRE11 and EXO1. Contrarily, a proteasomal component, ADRM1Rpn13, inhibited resection and was removed by CRL4WDR70-catalyzed ubiquitination upon commitment of extensive resection. HBx interfered with ADRM1Rpn13 degradation, leading to the imposition of ADRM1Rpn13-dependent resection barrier and consequent viral HRD subtype distinguishable from that caused by BRCA1 defect. Finally, we demonstrated that viral HRD in HBV-associated hepatocellular carcinoma can be exploited to restrict tumor progression. Our work clarifies the underlying mechanism of a virus-induced HRD subtype.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Vírus da Hepatite B/genética , Vírus da Hepatite B/metabolismo , Neoplasias Hepáticas/genética , Transativadores/genética , Transativadores/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Transcrição/genética , Hepatite B/genética , Recombinação Homóloga , Peptídeos e Proteínas de Sinalização Intracelular/genética
5.
Anal Chem ; 95(37): 13762-13768, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37661353

RESUMO

Imaging and tracking tools for natural cellular RNA with improved biocompatibility, specificity, and sensitivity are critical to understanding RNA function and providing insights into disease therapeutics. We developed a new genetically encoded sensor using fluorogenic allosteric aptamer (FaApt) for the sensitive imaging of the localization and dynamics of RNA targets in live cells. Target RNAs can be specifically recognized with our sensor by forming perfectly complementary duplexes, which in turn can induce allosteric structural changes of the sensor to refold the native conformation of fluorogenic RNA aptamers. We demonstrated the ability of the sensor to monitor the effect of tumor necrosis factor and small-molecule inhibitor on the expression abundance of CXCL1 and survivin mRNA in human cancer cells, respectively. The asymmetrical distribution of endogenous Squint mRNA was confirmed in developing zebrafish embryos through microinjection of FaApt probes. This study provides an effective molecular tool for sensitive imaging and tracking endogenous RNA in living cells. Due to the high specificity and small size of our sensor system, it is expected to be applied to early diagnosis of RNA marker-related diseases and real-time evaluation of the treatment process.


Assuntos
Aptâmeros de Nucleotídeos , RNA , Humanos , Animais , RNA/genética , Peixe-Zebra/genética , RNA Mensageiro , Aptâmeros de Nucleotídeos/genética , Diagnóstico por Imagem
6.
Heliyon ; 9(7): e18305, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539322

RESUMO

The gene expression networks of a single cell can be used to reveal cell type- and condition-specific patterns that account for cell states, cell identity, and its responses to environmental changes. We applied single cell sequencing datasets to define mRNA patterns and visualized potential cellular capacities among hepatocellular cancer cells. The expressing numbers and levels of genes were highly heterogenous among the cancer cells. The cellular characteristics were dependent strongly on the expressing numbers and levels of genes, especially oncogenes and anti-oncogenes, in an individual cancer cell. The transcriptional activations of oncogenes and anti-oncogenes were strongly linked to inherent multiple cellular programs, some of which oppose and contend against other processes, in a cancer cell. The gene expression networks of multiple cellular programs proliferation, differentiation, apoptosis, autophagy, epithelial-mesenchymal transition, ATP production, and neurogenesis coexisted in an individual cancer cell. The findings give rise a hypothesis that a cancer cell expresses balanced combinations of genes and undergoes a given biological process by rapidly transmuting gene expressing networks.

7.
Int J Biol Sci ; 19(10): 3226-3248, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37416774

RESUMO

Loss of function in transport protein particles (TRAPP) links a new set of emerging genetic disorders called "TRAPPopathies". One such disorder is NIBP syndrome, characterized by microcephaly and intellectual disability, and caused by mutations of NIBP/TRAPPC9, a crucial and unique member of TRAPPII. To investigate the neural cellular/molecular mechanisms underlying microcephaly, we developed Nibp/Trappc9-deficient animal models using different techniques, including morpholino knockdown and CRISPR/Cas mutation in zebrafish and Cre/LoxP-mediated gene targeting in mice. Nibp/Trappc9 deficiency impaired the stability of the TRAPPII complex at actin filaments and microtubules of neurites and growth cones. This deficiency also impaired elongation and branching of neuronal dendrites and axons, without significant effects on neurite initiation or neural cell number/types in embryonic and adult brains. The positive correlation of TRAPPII stability and neurite elongation/branching suggests a potential role for TRAPPII in regulating neurite morphology. These results provide novel genetic/molecular evidence to define patients with a type of non-syndromic autosomal recessive intellectual disability and highlight the importance of developing therapeutic approaches targeting the TRAPPII complex to cure TRAPPopathies.


Assuntos
Deficiência Intelectual , Microcefalia , Animais , Camundongos , Deficiência Intelectual/genética , Deficiência Intelectual/metabolismo , Microcefalia/genética , Microcefalia/metabolismo , Neuritos/fisiologia , Neurônios/metabolismo , Peixe-Zebra
8.
Signal Transduct Target Ther ; 8(1): 273, 2023 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-37455272

RESUMO

mRNA vaccines have emerged rapidly in recent years as a prophylactic and therapeutic agent against various diseases including cancer and infectious diseases. Improvements of mRNA vaccines have been underway, among which boosting of efficacy is of great importance. Pam2Cys, a simple synthetic metabolizable lipoamino acid that signals through Toll-like receptor (TLR) 2/6 pathway, eliciting both humoral and cellular adaptive immune responses, is an interesting candidate adjuvant. To investigate the enhancement of the efficacies of mRNA vaccines by Pam2Cys, the adjuvant was incorporated into mRNA-lipid nanoparticles (LNPs) to achieve co-delivery with mRNA. Immunization with the resulting mRNA-LNPs (Pam2Cys) shaped up the immune milieu in the draining lymph nodes (dLNs) through the induction of IL-12 and IL-17, among other cytokines. Antigen presentation was carried out mainly by migratory and dLN-resident conventional type 2 DCs (cDC2s) and significantly more potent antitumor responses were triggered in both prophylactic and therapeutic tumor models in a CD4+ and CD8+ T cell-dependent fashion. Accompanying memory antitumor immunity was also established. Moreover, the vaccine also stimulated much more robust humoral and cellular immunity in a surrogate COVID-19 prophylactic model. Last but not the least, the new vaccines exhibited good preliminary safety profiles in murine models. These facts warrant future development of Pam2Cys-incorporated mRNA vaccines or relevant mRNA therapeutics for clinical application.


Assuntos
COVID-19 , Doenças Transmissíveis , Neoplasias , Vacinas , Animais , Camundongos , Receptor 2 Toll-Like/genética , COVID-19/prevenção & controle , Adjuvantes Imunológicos/farmacologia , Neoplasias/genética , Neoplasias/terapia , RNA Mensageiro/genética
9.
iScience ; 26(3): 106273, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36936789

RESUMO

DOPEY2 has been shown to be associated with Down syndrome and PCDH7 might be involved in Rett syndrome and MECP2 duplication syndrome. The mechanism how both proteins play roles in these syndromes are largely unknown. Here, we show that Dopey2 and Pcdh7 balance the proliferation and differentiation of neural stem cells and progenitors during embryonic neurogenesis to generate proper size and architecture of zebrafish brains. Dopey2 and Pcdh7 mutually restricted expression of each other in zebrafish embryos. Dopey2 was responsible for the proliferation of neural stem cells/progenitors, whereas Pcdh7 was responsible for the differentiation of neural stem cells/progenitors. Both proteins were shown to orchestrate the proper development and arrangement of neural cells in zebrafish embryonic brains. The results provide an insight into mechanisms to understand how the embryonic brain is constituted and how developmental defects occur in the brains of patients with Down syndrome, Rett syndrome, or MECP2 duplication syndrome.

10.
Signal Transduct Target Ther ; 8(1): 3, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36588101

RESUMO

Autism spectrum disorder (ASD) affects 1-2% of all children and poses a great social and economic challenge for the globe. As a highly heterogeneous neurodevelopmental disorder, the development of its treatment is extremely challenging. Multiple pathways have been linked to the pathogenesis of ASD, including signaling involved in synaptic function, oxytocinergic activities, immune homeostasis, chromatin modifications, and mitochondrial functions. Here, we identify secretagogin (SCGN), a regulator of synaptic transmission, as a new risk gene for ASD. Two heterozygous loss-of-function mutations in SCGN are presented in ASD probands. Deletion of Scgn in zebrafish or mice leads to autism-like behaviors and impairs brain development. Mechanistically, Scgn deficiency disrupts the oxytocin signaling and abnormally activates inflammation in both animal models. Both ASD probands carrying Scgn mutations also show reduced oxytocin levels. Importantly, we demonstrate that the administration of oxytocin and anti-inflammatory drugs can attenuate ASD-associated defects caused by SCGN deficiency. Altogether, we identify a convergence between a potential autism genetic risk factor SCGN, and the pathological deregulation in oxytocinergic signaling and immune responses, providing potential treatment for ASD patients suffering from SCGN deficiency. Our study also indicates that it is critical to identify and stratify ASD patient populations based on their disease mechanisms, which could greatly enhance therapeutic success.


Assuntos
Transtorno do Espectro Autista , Secretagoginas , Animais , Camundongos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Ocitocina/genética , Ocitocina/metabolismo , Fatores de Risco , Secretagoginas/genética , Secretagoginas/metabolismo , Peixe-Zebra/metabolismo , Humanos
11.
Commun Biol ; 5(1): 1326, 2022 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463319

RESUMO

Fibroblasts and myofibroblasts are major mesenchymal cells in the lamina propria of colon mucosa and in colon cancer tissues. Detailed insight into the highly specific populations of fibroblasts and myofibroblasts is required to understand the integrity and homeostasis of human colon mucosa and colon cancer. Based on gene expression profiles of single cells, we identified fibroblast populations that produce extracellular matrix components, Wnt ligand- and BMP-secreting fibroblasts, chemokine- and chemokine ligand-generating fibroblasts, highly activated fibroblasts, immune-modulating fibroblasts, epithelial cell-modulating myofibroblasts, stimuli-responsive myofibroblasts, proliferating myofibroblasts, fibroblast-like myofibroblasts, matrix producing myofibroblasts, and contractile myofibroblasts in human colon mucosa. In colon cancer tissue, the compositions of fibroblasts and myofibroblasts were highly altered, as were the expressing patterns of genes including BMPs, Wnt ligands, chemokines, chemokine ligands, growth factors and extracellular matrix components in fibroblasts and myofibroblasts. Our work expands the working atlas of fibroblasts and myofibroblasts and provides a framework for interrogating the complexity of stromal cells in human healthy colon mucosa and colon cancer tissues.


Assuntos
Neoplasias do Colo , Fibroblastos , Humanos , Ligantes , Miofibroblastos , Neoplasias do Colo/genética
12.
Cell Rep ; 39(5): 110750, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35508129

RESUMO

Bone stromal cells are critical for bone homeostasis and regeneration. Growing evidence suggests that non-stem bone niche cells support bone homeostasis and regeneration via paracrine mechanisms, which remain to be elucidated. Here, we show that physiologically quiescent SM22α-lineage stromal cells expand after bone injury to regulate diverse processes of intramembranous bone regeneration. The majority of SM22α-lineage cells neither act as stem cells in vivo nor show their expression patterns. Dysfunction of SM22α-lineage niche cells induced by loss of platelet-derived growth factor receptor ß (PDGFRß) impairs bone repair. We further show that PDGFRß-triggered hydrogen sulfide (H2S) generation in SM22α-lineage niche cells facilitates osteogenesis and angiogenesis and suppresses overactive osteoclastogenesis. Collectively, these data demonstrate that non-stem SM22α-lineage niche cells support the niche for bone regeneration with a PDGFRß/H2S-dependent regulatory mechanism. Our findings provide further insight into non-stem bone stromal niche cell populations and niche-regulation strategy for bone repair.


Assuntos
Sulfeto de Hidrogênio , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Regeneração Óssea , Hidrogênio , Sulfeto de Hidrogênio/farmacologia , Osteogênese , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo
13.
Cancer Cell Int ; 22(1): 158, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440048

RESUMO

BACKGROUND: Several nervous and nerve-related biomarkers have been detected in colorectal cancer (CRC) and can contribute to the progression of CRC. However, the role of leucine-rich repeat neuronal 4 (LRRN4), a recently identified neurogenic marker, in CRC remains unclear. METHODS: We examined the expression and clinical outcomes of LRRN4 in CRC from TCGA-COREAD mRNA-sequencing datasets and immunohistochemistry in a Chinese cohort. Furthermore, colony formation, flow cytometry, wound healing assays and mouse xenograft models were used to investigate the biological significance of LRRN4 in CRC cell lines with LRRN4 knockdown or overexpression in vitro and in vivo. In addition, weighted coexpression network analysis, DAVID and western blot analysis were used to explore the potential molecular mechanism. RESULTS: We provide the first evidence that LRRN4 expression, at both the mRNA and protein levels, was remarkably high in CRC compared to controls and positively correlated with the clinical outcome of CRC patients. Specifically, LRRN4 was an independent prognostic factor for progression-free survival and overall survival in CRC patients. Further functional experiments showed that LRRN4 promoted cell proliferation, cell DNA synthesis and cell migration and inhibited apoptosis. Knockdown of LRRN4 can correspondingly decrease these effects in vitro and can significantly suppress the growth of xenografts. Several biological functions and signaling pathways were regulated by LRRN4, including proteoglycans in cancer, glutamatergic synapse, Ras, MAPK and PI3K. LRRN4 knockdown resulted in downregulation of Akt, p-Akt, ERK1/2 and p-ERK1/2, the downstream of the Ras/MAPK signaling pathway, overexpression of LRRN4 leaded to the upregulation of these proteins. CONCLUSIONS: Our results suggest that LRRN4 could be a biological and molecular determinant to stratify CRC patients into distinct risk categories, and mechanistically, this is likely attributable to LRRN4 regulating several malignant phenotypes of neoplastic cells via RAS/MAPK signal pathways.

14.
Biosens Bioelectron ; 198: 113827, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34861524

RESUMO

Visualizing the dynamics of ATP in living cells is key to understanding cellular energy metabolism and related diseases. However, the live-cell applications of current methods are still limited due to challenges in biological compatibility and sensitivity to pH. Herein, a novel label-free fluorescent " turn-on " biosensor for monitoring ATP in living bacterias and mammalian cells was developed. This biosensor (Broc-ATP) employed heterobifunctional aptamers to detect ATP with high sensitivity in vitro. In our system, a very useful tandem method was established by combining four Broc-ATPs with 3 × F30 three-way junction scaffold to construct an intracellular biosensor that achieves sufficient fluorescence to respond to intracellular ATP. This intracellular biosensor can be used for sensitive and specific dynamic imaging of ATP in mammalian cells. Hence, this genetically encoded biosensor provides a robust and efficient tool for the detection of intracellular ATP dynamics and 3 × F30 tandem method expands the application of heterobifunctional aptamers in mammalian cells.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Trifosfato de Adenosina , Animais , Metabolismo Energético , Corantes Fluorescentes , Oligonucleotídeos
15.
Proc Natl Acad Sci U S A ; 118(36)2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34462354

RESUMO

The molecular events that determine the recycling versus degradation fates of internalized membrane proteins remain poorly understood. Two of the three members of the SNX-FERM family, SNX17 and SNX31, utilize their FERM domain to mediate endocytic trafficking of cargo proteins harboring the NPxY/NxxY motif. In contrast, SNX27 does not recycle NPxY/NxxY-containing cargo but instead recycles cargo containing PDZ-binding motifs via its PDZ domain. The underlying mechanism governing this divergence in FERM domain binding is poorly understood. Here, we report that the FERM domain of SNX27 is functionally distinct from SNX17 and interacts with a novel DLF motif localized within the N terminus of SNX1/2 instead of the NPxY/NxxY motif in cargo proteins. The SNX27-FERM-SNX1 complex structure reveals that the DLF motif of SNX1 binds to a hydrophobic cave surrounded by positively charged residues on the surface of SNX27. The interaction between SNX27 and SNX1/2 is critical for efficient SNX27 recruitment to endosomes and endocytic recycling of multiple cargoes. Finally, we show that the interaction between SNX27 and SNX1/2 is critical for brain development in zebrafish. Altogether, our study solves a long-standing puzzle in the field and suggests that SNX27 and SNX17 mediate endocytic recycling through fundamentally distinct mechanisms.


Assuntos
Encéfalo/crescimento & desenvolvimento , Domínios FERM , Nexinas de Classificação/metabolismo , Animais , Encéfalo/metabolismo , Endocitose , Transportador de Glucose Tipo 1/metabolismo , Humanos , Neurônios/citologia , Ligação Proteica , Transporte Proteico , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Nexinas de Classificação/química , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
16.
Int J Clin Exp Pathol ; 14(5): 646-652, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093950

RESUMO

OBJECTIVE: This study explored and analyzed the expression of LncRNA NEAT1 in peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE) and its correlation with Th1/Th2 balance. METHODS: We chose 97 SLE patients admitted in our hospital from Jun. 2016 to Feb. 2019 as SLE group, and randomly selected 50 healthy volunteers that underwent physical examination in our hospital during the same period as control group. We detected the expression of LncRNA NEAT1 in PBMCs of the two groups of subjects by qRT-PCR, the degree of Th1 and Th2 cells in both groups by flow cytometry, and the expression of TFN-γ and IL-4 in both groups by ELISA. RESULTS: The relative expression of LncRNA NEAT1 in PBMCs of SLE group was higher than that of control group (P<0.05). The proportion of Th1 and the ratio of Th1/Th2 cells in PBMCs were markedly lower in the SLE group than the control group (P<0.05), while the proportion of Th2 was higher in the SLE group than the control group (P<0.05). IFN-γ level in SLE group was much lower than the control group (P<0.05), while IL-4 level was evidently higher in the SLE group than in controls (P<0.05). The expression of LncRNA NEAT1 in PBMCs of SLE group was notably negatively correlated with Th1 proportion and Th1/Th2 ratio (P<0.05), while positively correlated with Th2 proportion (P<0.05). CONCLUSION: LncRNA NEAT1 in PBMCs of SLE patients is abnormally highly expressed, and this expression is negatively correlated with Th1/Th2 balance. These two factors may interact and jointly affect the occurrence and progression of SLE.

17.
Future Sci OA ; 7(5): FSO690, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34046192

RESUMO

OBJECTIVE: To establish a convenient and simple flow cytometry immunophenotyping panel to explore immune cellular alterations and potential cellular biomarkers in systemic lupus erythematosus. MATERIALS AND METHODS: This is a cross-sectional, case-control study including 60 patients with systemic lupus erythematosus and 20 sex- and age-matched healthy controls. A 14-color immunophenotyping panel was applied to detect proportions of circulating immune mononuclear cells, and comparisons between patients and healthy controls, and subgroups of patients, were performed. Correlations between cellular proportions and other parameters were investigated. RESULTS: After multivariate analysis, significantly decreased proportions of CD4-CD8- T cells, natural killer cells and innate lymphoid cells were observed in patients compared with healthy controls. The proportions of basophils were decreased significantly in patients with lupus nephritis (LN) compared with those in patients without LN. CONCLUSION: In the present study, we found that basophil proportions may be a biomarker of LN.

18.
Nat Struct Mol Biol ; 28(5): 1-12, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33986552

RESUMO

GDP-mannose (GDP-Man) is a key metabolite essential for protein glycosylation and glycophosphatidylinositol anchor synthesis, and aberrant cellular GDP-Man levels have been associated with multiple human diseases. How cells maintain homeostasis of GDP-Man is unknown. Here, we report the cryo-EM structures of human GMPPA-GMPPB complex, the protein machinery responsible for GDP-Man synthesis, in complex with GDP-Man or GTP. Unexpectedly, we find that the catalytically inactive subunit GMPPA displays a much higher affinity to GDP-Man than the active subunit GMPPB and, subsequently, inhibits the catalytic activity of GMPPB through a unique C-terminal loop of GMPPA. Importantly, disruption of the interactions between GMPPA and GMPPB or the binding of GDP-Man to GMPPA in zebrafish leads to abnormal brain development and muscle abnormality, analogous to phenotypes observed in individuals carrying GMPPA or GMPPB mutations. We conclude that GMPPA acts as a cellular sensor to maintain mannose homeostasis through allosterically regulating GMPPB.


Assuntos
Guanosina Difosfato Manose/metabolismo , Nucleotidiltransferases , Animais , Microscopia Crioeletrônica , Células HEK293 , Humanos , Nucleotidiltransferases/química , Nucleotidiltransferases/metabolismo , Ligação Proteica , Domínios Proteicos , Peixe-Zebra
19.
J Invest Dermatol ; 141(10): 2521-2529.e4, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33839145

RESUMO

Keloid disease is a benign skin disease that does not have an effective therapy. More and more research shows that epidermal abnormalities are involved in keloid pathogenesis. Little is known about the relationship between the abnormal epidermal immunophenotype and clinical outcome. Nine-color flow cytometry with computational analysis was performed to detect the altered cellular subpopulation distribution in keloid lesions. Receiver operating characteristic curves were drawn to compare predictive ability between the alteration of cell subgroup frequency and the Vancouver Scar Scale. The frequency of CD49fhi/CD29+/TLR7+ cellular subsets increased in the keloid epidermis compared with that in the healthy control. CD49fmid-hi/CD29+/TLR7+/CD24+ cellular subpopulation level was increased significantly in keloids, whereas CD49flo-mid/CD29‒/TLR7‒/CD24‒ cellular subpopulation frequency was decreased. The CD49flo/CD29‒/TLR7‒/CD24+/CD117+ cellular subpopulation showed an increased frequency during recurrence with a sensitivity of 66.7% and specificity of 91.7%. The area under the curve was 0.806 for cellular subpopulation analysis, which was higher than the area under the curve for the Vancouver Scar Scale (0.583). The alteration of keloid epidermal subpopulation frequency is related to recurrence, which will provide an optional predictive marker for keloid recurrence and a potential target subset for investigating the generation of keloid.


Assuntos
Células Epidérmicas/patologia , Citometria de Fluxo/métodos , Queloide/patologia , Células Epidérmicas/classificação , Células Epidérmicas/imunologia , Feminino , Humanos , Imunofenotipagem , Integrina alfa6/análise , Integrina beta1/análise , Queloide/imunologia , Masculino , Recidiva , Receptor 7 Toll-Like/análise
20.
Aging (Albany NY) ; 13(8): 12067-12085, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793420

RESUMO

MicroRNAs (miRNAs) are known to drive the pathogenesis of colorectal cancer (CRC) via the regulation of cancer stem cells (CSCs). We studied the miRNA expression profile of primary CSCs isolated from patients with CRC (pCRCSCs). Compared to pCRCSC-derived differentiated cells, 98 differentially expressed miRNAs were identified in pCRCSCs. Target genes encoding pCRCSC-related miRNAs were identified using a combination of miRNA target databases and miRNA-mRNA regulatory networks from the same patient. The pCRCSC-related miRNA target genes were associated with pathways contributing to malignant phenotypes, including I-kappa B kinase/NF-kappa B signaling, signal transduction by p53 class mediator, Ras signaling, and cGMP-PKG signaling. The pCRCSC-related miRNA expression signature was independently associated with poor overall survival in both the training and validation cohorts. We have thus identified several pCRCSC-related miRNAs with oncogenic potential that could serve as prognostic biomarkers for CRC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/mortalidade , MicroRNAs/metabolismo , Modelos Genéticos , Células-Tronco Neoplásicas/metabolismo , Idoso , Animais , Colectomia , Colo/patologia , Colo/cirurgia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cultura Primária de Células , Prognóstico , RNA Mensageiro/genética , Medição de Risco/métodos , Transdução de Sinais/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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