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1.
PLoS Genet ; 17(8): e1009770, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34460822

RESUMO

The eye color of birds, generally referring to the color of the iris, results from both pigmentation and structural coloration. Avian iris colors exhibit striking interspecific and intraspecific variations that correspond to unique evolutionary and ecological histories. Here, we identified the genetic basis of pearl (white) iris color in domestic pigeons (Columba livia) to explore the largely unknown genetic mechanism underlying the evolution of avian iris coloration. Using a genome-wide association study (GWAS) approach in 92 pigeons, we mapped the pearl iris trait to a 9 kb region containing the facilitative glucose transporter gene SLC2A11B. A nonsense mutation (W49X) leading to a premature stop codon in SLC2A11B was identified as the causal variant. Transcriptome analysis suggested that SLC2A11B loss of function may downregulate the xanthophore-differentiation gene CSF1R and the key pteridine biosynthesis gene GCH1, thus resulting in the pearl iris phenotype. Coalescence and phylogenetic analyses indicated that the mutation originated approximately 5,400 years ago, coinciding with the onset of pigeon domestication, while positive selection was likely associated with artificial breeding. Within Aves, potentially impaired SLC2A11B was found in six species from six distinct lineages, four of which associated with their signature brown or blue eyes and lack of pteridine. Analysis of vertebrate SLC2A11B orthologs revealed relaxed selection in the avian clade, consistent with the scenario that during and after avian divergence from the reptilian ancestor, the SLC2A11B-involved development of dermal chromatophores likely degenerated in the presence of feather coverage. Our findings provide new insight into the mechanism of avian iris color variations and the evolution of pigmentation in vertebrates.


Assuntos
Columbidae/genética , Cor de Olho/genética , Cor de Olho/fisiologia , Animais , Evolução Biológica , Evolução Molecular , Olho/metabolismo , Perfilação da Expressão Gênica/métodos , Estudo de Associação Genômica Ampla , Genótipo , Proteínas Facilitadoras de Transporte de Glucose/genética , Iris/metabolismo , Mutação , Fenótipo , Filogenia , Pigmentação/genética
2.
PLoS Genet ; 17(8): e1009727, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34407079

RESUMO

Vps13 family proteins are proposed to function in bulk lipid transfer between membranes, but little is known about their regulation. During sporulation of Saccharomyces cerevisiae, Vps13 localizes to the prospore membrane (PSM) via the Spo71-Spo73 adaptor complex. We previously reported that loss of any of these proteins causes PSM extension and subsequent sporulation defects, yet their precise function remains unclear. Here, we performed a genetic screen and identified genes coding for a fragment of phosphatidylinositol (PI) 4-kinase catalytic subunit and PI 4-kinase noncatalytic subunit as multicopy suppressors of spo73Δ. Further genetic and cytological analyses revealed that lowering PI4P levels in the PSM rescues the spo73Δ defects. Furthermore, overexpression of VPS13 and lowering PI4P levels synergistically rescued the defect of a spo71Δ spo73Δ double mutant, suggesting that PI4P might regulate Vps13 function. In addition, we show that an N-terminal fragment of Vps13 has affinity for the endoplasmic reticulum (ER), and ER-plasma membrane (PM) tethers localize along the PSM in a manner dependent on Vps13 and the adaptor complex. These observations suggest that Vps13 and the adaptor complex recruit ER-PM tethers to ER-PSM contact sites. Our analysis revealed that involvement of a phosphoinositide, PI4P, in regulation of Vps13, and also suggest that distinct contact site proteins function cooperatively to promote de novo membrane formation.


Assuntos
1-Fosfatidilinositol 4-Quinase/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Esporos Fúngicos/genética , 1-Fosfatidilinositol 4-Quinase/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Transporte/genética , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Membranas/metabolismo , Membranas Mitocondriais/metabolismo , Transporte Proteico , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
3.
J Sci Food Agric ; 104(9): 5603-5613, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38363126

RESUMO

BACKGROUND: Acidic lipases with high catalytic activities under acidic conditions have important application values in the food, feed and pharmaceutical industries. However, the availability of acidic lipases is still the main obstacle to their industrial applications. Although a novel acidic lipase Rasamsonia emersonii (LIPR) was heterologously expressed in Escherichia coli, the expression level was unsatisfactory. RESULTS: To achieve the high-efficiency expression and secretion of LIPR in Pichia pastoris GS115, the combinatorial optimization strategy was adopted including gene codon preference, signal peptide, molecular chaperone co-expression and disruption of vacuolar sorting receptor VPS10. The activity of the combinatorial optimization engineered strain in a shake flask reached 1480 U mL-1, which was 8.13 times greater than the P. pastoris GS115 parental strain. After high-density fermentation in a 5-L bioreactor, the highest enzyme activity reached as high as 11 820 U mL-1. LIPR showed the highest activity at 40 °C and pH 4.0 in the presence of Ca2+ ion. LIPR exhibited strong tolerance to methanol, indicating its potential application in biodiesel biosynthesis. Moreover, the gastrointestinal digestion simulation results demonstrated that LIPR was tolerant to pepsin and trypsin, but its activity was inhibited by sodium taurodeoxycholate. CONCLUSION: This study provided an effective approach for the high expression of acidic lipase LIPR. LIPR was more appropriate for lipid digestion in the stomach than in intestine according to the gastrointestinal digestion simulation results. © 2024 Society of Chemical Industry.


Assuntos
Digestão , Proteínas Fúngicas , Lipase , Lipase/genética , Lipase/metabolismo , Lipase/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/enzimologia , Concentração de Íons de Hidrogênio , Saccharomycetales/genética , Saccharomycetales/enzimologia , Saccharomycetales/metabolismo , Expressão Gênica , Estabilidade Enzimática , Pichia/genética , Pichia/metabolismo , Humanos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Modelos Biológicos , Fermentação
4.
Opt Express ; 31(13): 20740-20749, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381190

RESUMO

We proposed and demonstrated a highly efficient sub-microscale focusing from a GaN green laser diode (LD) integrated with double-sided asymmetric metasurfaces. The metasurfaces consist of two nanostructures in a GaN substrate: nanogratings on one side and a geometric phase based metalens on the other side. When it was integrated on the edge emission facet of a GaN green LD, linearly polarized emission was firstly converted to the circularly polarized state by the nanogratings functioning as a quarter-wave plate, the phase gradient was then controlled by the metalens on the exit side. In the end, the double-sided asymmetric metasurfaces achieve a sub micro-focusing from linearly polarized states. Experimental results show the full width at half maximum of the focused spot size is about 738 nm at the wavelength 520 nm and the focusing efficiency is about 72.8%. Our results lay a foundation for the multi-functional applications in optical tweezers, laser direct writing, visible light communication, and biological chip.

5.
Environ Sci Technol ; 57(1): 128-138, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36525597

RESUMO

In situ aging can change biochar properties, influencing their ecosystem benefits or risks over time. However, there is a lack of field verification of laboratory methods that attempt simulation of long-term natural aging of biochar. We exploited a decade-scale natural charcoal (a proxy for biochar) aging event to determine which lab-aging methods best mimicked field aging. We oxidized charcoal by ultraviolet A radiation (UVA), H2O2, or monochloramine (NH2Cl), and compared it to 10-year field-aged charcoal. We considered seven selected charcoal properties related to surface chemistry and organic matter release, and found that oxidation with 30% H2O2 most representatively simulated 10-year field aging for six out of seven properties. UVA aging failed to approximate oxidation levels while showing a distinctive dissolved organic carbon (DOC) release pattern. NH2Cl-aged charcoal was the most different, showing an increased persistent free radical (PFR) concentration and lower hydrophilicity. All lab oxidation techniques overpredicted polycyclic aromatic hydrocarbon release. The O/C ratio was well-correlated with DOC release, PFR concentration, surface charge, and charcoal pH, indicating the possibility to accurately predict biochar aging with a reduced suite of physicochemical properties. Overall, our rapid and verified lab-aging methods facilitate research toward derisking and enhancing long-term benefits of biochar application.


Assuntos
Carvão Vegetal , Poluentes do Solo , Carvão Vegetal/química , Solo/química , Ecossistema , Peróxido de Hidrogênio
6.
Phys Chem Chem Phys ; 25(15): 10935-10945, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37016831

RESUMO

This paper describes a tin oxide and copper doped tin oxide gas sensing material synthesized by a biological template method and simple hydrothermal reaction, which were used for the preparation of a gas sensor array. The sensor array is combined with the Sparrow Search Algorithm optimized BP neural network algorithm (SSA-BP) to predict and analyze the concentration of indoor toxic gases, including ammonia, xylene, and formaldehyde. Granular SnO2 was prepared by the biological template method and Cu/SnO2 doped with different copper ion concentrations was prepared by the hydrothermal method. The morphology of the synthesized nanomaterials was characterized by SEM, and the elemental composition and chemical state of the main elements were analyzed by XRD and XPS. The PL emission observed in the visible region is attributed to the defect level gap caused by oxygen. The optimal operating temperature, sensitivity, response/recovery time and the long-term stability of the sensor array have been studied. By combining the sensor array with the neural network algorithm in a simulated indoor environment at four humidity levels, the concentration information of the gas mixtures could be well predicted and the predicted concentration error was less than 0.84 ppm. Therefore, the sensor array prepared in this study combined with the SSA-BP algorithm achieved good results in predicting the concentrations of the three toxic mixtures.

7.
J Nanobiotechnology ; 21(1): 175, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37264420

RESUMO

BACKGROUND: Congenital disorders of glycosylation (CDGs) are genetic diseases caused by gene defects in glycan biosynthesis pathways, and there is an increasing number of patients diagnosed with CDGs. Because CDGs show many different clinical symptoms, their accurate clinical diagnosis is challenging. Recently, we have shown that liposome nanoparticles bearing the ALG1-CDG and PMM2-CDG biomarkers (a tetrasaccharide: Neu5Ac-α2,6-Gal-ß1,4-GlcNAc-ß1,4-GlcNAc) stimulate a moderate immune response, while the generated antibodies show relatively weak affinity maturation. Thus, mature antibodies with class switching to IgG are desired to develop high-affinity antibodies that may be applied in medical applications. RESULTS: In the present study, a liposome-based vaccine platform carrying a chemoenzymatic synthesized phytanyl-linked tetrasaccharide biomarker was optimized. The liposome nanoparticles were constructed by dioleoylphosphatidylcholine (DOPC) to improve the stability and immunogenicity of the vaccine, and adjuvanted with the NKT cell agonist PBS57 to generate high level of IgG antibodies. The results indicated that the reformulated liposomal vaccine stimulated a stronger immune response, and PBS57 successfully induce an antibody class switch to IgG. Further analyses of IgG antibodies elicited by liposome vaccines suggested their specific binding to tetrasaccharide biomarkers, which were mainly IgG2b isotypes. CONCLUSIONS: Immunization with a liposome vaccine carrying a carbohydrate antigen and PBS57 stimulates high titers of CDG biomarker-specific IgG antibodies, thereby showing great potential as a platform to develop rapid diagnostic methods for ALG1-CDG and PMM2-CDG.


Assuntos
Células T Matadoras Naturais , Vacinas , Humanos , Lipossomos , Switching de Imunoglobulina , Células T Matadoras Naturais/metabolismo , Oligossacarídeos , Adjuvantes Imunológicos , Biomarcadores/metabolismo , Imunoglobulina G , Imunidade
8.
Sensors (Basel) ; 23(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37112263

RESUMO

Quartz tuning forks (QTFs) are self-sensing and possess a high quality factor, allowing them to be used as probes for atomic force microscopes (AFMs) for which they offer nano-scale resolution of sample images. Since recent work has revealed that utilizing higher-order modes of QTFs can offer better resolution of AFM images and more information on samples, it is necessary to understand the relationship between the vibration characteristics of the first two symmetric eigenmodes of quartz-based probes. In this paper, a model that combines the mechanical and electrical characteristics of the first two symmetric eigenmodes of a QTF is presented. Firstly, the relationships between the resonant frequency, amplitude, and quality factor between the first two symmetric eigenmodes are theoretically derived. Then, a finite element analysis is conducted to estimate the dynamic behaviors of the analyzed QTF. Finally, experimental tests are executed to verify the validity of the proposed model. The results indicate that the proposed model can accurately describe the dynamic properties of a QTF in the first two symmetric eigenmodes either under electrical or mechanical excitation, which will provide a reference for the description of the relationship between the electrical and mechanical responses of the QTF probe in the first two symmetric eigenmodes as well as the optimization of higher modal responses of the QTF sensor.

9.
Nano Lett ; 22(21): 8670-8678, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36256439

RESUMO

Yellow-green luminescence (YGL) competes with near-bandgap emission (NBE) for carrier recombination channels, thereby reducing device efficiency; yet uncovering the origin of YGL remains a major challenge. In this paper, nearly stress-free and low dislocation density self-assembled GaN microdisks were synthesized by Na-flux method. The YGL of GaN microdisks highly depend on their polar facets. Variable accelerating voltage/power CL, variable temperature PL, and Raman spectroscopy are further performed to clarify the origin of polarity dependence of GaN microdisk YGL behavior, which indicates its independence of dislocations, surface effects, stress, crystalline quality, and gallium vacancies. It was found that the incorporation ability of carbon impurities in the polar (0001) facet is greater than that in the semipolar (101̅1) facets, producing higher content of CN or CNON defects, resulting in a more pronounced YGL in the polar (0001) facet of GaN.

10.
J Sci Food Agric ; 103(1): 339-348, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35871484

RESUMO

BACKGROUND: Rare sugars have become promising 'sugar alternatives' because of their low calories and unique physiological functions. Among the family of rare sugars, d-allulose is one of the sugars attracting interest. Ketose 3-epimerases (KEase), including d-tagatose 3-epimerase (DTEase) and d-allulose 3-epimerase (DAEase), are mainly used for d-allulose production. RESULTS: In this study, a putative xylose isomerase from Caballeronia insecticola was characterized and identified as a novel DAEase. Caballeronia insecticola DAEase displayed prominent enzymatic properties, and 150 g L-1 d-allulose was produced from 500 g L-1 d-fructose in 45 min with a conversion rate of 30% and high productivity of 200 g L-1 h-1 . Furthermore, DAEase was employed in a phosphorylation-dephosphorylation cascade reaction, which significantly increased the conversion rate of d-allulose. Under optimized conditions, the conversion rate of d-allulose was approximately 100% when the concentration of d-fructose was 50 mmol L-1 . CONCLUSION: This research described a very beneficial and facile approach for d-allulose production based on C. insecticola DAEase. © 2022 Society of Chemical Industry.


Assuntos
Frutose , Racemases e Epimerases , Racemases e Epimerases/genética , Concentração de Íons de Hidrogênio , Frutose/química
11.
Yi Chuan ; 45(8): 669-683, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37609818

RESUMO

In human cells, there are more than 146 glycosylphosphatidylinositol-anchored proteins (GPI-APs), including receptors, ligands, adhesion molecules and enzymes. The proteins are associated with membrane microdomains called lipid rafts through GPI, and plays a variety of important biological functions. At present, plenty of studies have been carried out on the biosynthesis of GPI-APs. The biosynthesis of GPI-APs requires at least 20 steps, and more than 40 GPI biosynthetic genes have been identified. However, it remains unclear how expression of GPI-AP related genes is regulated in normal and cancer tissues. In this study, we utilized gene expression data from both the TCGA database and GTEx portal to analysis the gene expression involved in GPI-AP biosynthesis and encoding GPI-APs in normal and cancer tissues. In order to perform a comprehensive analysis, we employed the GlycoMaple, a tool that is specifically designed to analyze glycosylation pathways. The results showed that compared with normal tissues, the expression of genes involved in GPI-AP biosynthesis in cancer tissues such as early glioma, glioblastoma multiforme, pancreatic cancer, testicular germ cell carcinoma, skin primary cutaneous melanoma and skin metastatic cutaneous melanoma, was changed significantly. Particularly, the expression of PIGY in these six cancers was increased. In addition, the expression of CD14, a GPI-AP gene, was increased in these six cancers. The expression of GAS1, GPC2 and GPC4 was increased only in early glioma and glioblastoma multiforme indicating that some GPI-APs such as GAS1 can be used as biomarkers of glioma. This study provides new insights into the expression of GPI-AP related genes in normal and cancer tissues, and lays a solid foundation for the development of GPI-APs as biomarkers.


Assuntos
Glioblastoma , Glioma , Melanoma , Neoplasias Cutâneas , Humanos , Glicosilfosfatidilinositóis/genética , Melanoma Maligno Cutâneo
12.
Cell Commun Signal ; 20(1): 138, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076237

RESUMO

BACKGROUND: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal tumours of the gastrointestinal tract and are characterized by activating mutations of c-KIT or PDGFRa receptor tyrosine kinases (RTKs). Despite the clinical success of tyrosine kinase inhibitors (TKIs), more than half of GIST patients develop resistance due to a second mutation. Cyclin-dependent kinase 7 (CDK7) is the catalytic subunit of CDK-activating kinase (CAK), and it plays an important role in the regulation of cell cycle transitions and gene transcription. THZ1, a CDK7 inhibitor, exhibits a dose-dependent inhibitory effect in various cancers. METHODS: Data from the public GEO database and tissue microarray were used to analyse the gene expression levels of CDKs in GISTs. The impact of CDK7 knockdown and the CDK7 inhibitor THZ1 on GIST progression was investigated in vitro using CCK-8, colony formation, and flow cytometry assays and in vivo using a xenograft mouse model. RNA sequencing was performed to investigate the mechanism of GIST cell viability impairment mediated by THZ1 treatment. RESULTS: Our study demonstrated that CDK7 is relatively overexpressed in high-risk GISTs and predicts a poor outcome. A low concentration of THZ1 exhibited a pronounced antineoplastic effect in GIST cells in vivo and in vitro. Moreover, THZ1 exerted synergistic anticancer effects with imatinib. THZ1 treatment resulted in transcriptional modulation by inhibiting the phosphorylation of Ser2, Ser5, and Ser7 within RNA polymerase II (RNAPII). c-KIT, an oncogene driver of GIST, was transcriptionally repressed by THZ1 treatment or CDK7 knockdown. Transcriptome sequencing analysis showed that OSR1 acts as a downstream target of CDK7 and regulates c-KIT expression. Taken together, our results highlight elevated CDK7 expression as a predictor of poor outcome in GIST and present the combination of CDK7 and RTK inhibitors as a potent therapeutic strategy to improve the efficacy of GIST treatment. Video abstract.


Assuntos
Antineoplásicos , Tumores do Estroma Gastrointestinal , Fenilenodiaminas/farmacologia , Pirimidinas/farmacologia , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/metabolismo , Humanos , Camundongos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Quinase Ativadora de Quinase Dependente de Ciclina
13.
Nanomedicine ; : 102610, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36257504

RESUMO

Cancer therapies are limited by poor drug penetration that impedes effective tumor treatment. This was overcome in the present study by loading the immune reaction inducing nanocarriers of the bacterial outer membrane vesicles (OMVs) and doxorubicin (DOX) into the natural immunity platform OMV via incubation. Drug accumulation at the tumor site was improved by using the targeting peptide 6-Mal- Arg-Gly-Asp (RGD) on the surface of OMVs to increase internalization via binding to cell surface integrin αvß3. OMVs stimulate immune responses by reversing the immune-suppressive tumor microenvironment (TME) via decreasing TAM and Treg, increasing CD8+ T and M1, and promoting DC maturation. The combination of DOX and OMVs compensates for the shortcomings of monotherapy (e.g., chemotherapy and immunotherapy) and amplifies the therapeutic efficacy of cancer treatment, while aiding selection of novel nanocarriers and development of effective therapeutic regimens.

14.
J Biol Chem ; 295(48): 16393-16410, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-32967966

RESUMO

The protein folding and lipid moiety status of glycosylphosphatidylinositol-anchored proteins (GPI-APs) are monitored in the endoplasmic reticulum (ER), with calnexin playing dual roles in the maturation of GPI-APs. In the present study, we investigated the functions of calnexin in the quality control and lipid remodeling of GPI-APs in the ER. By directly binding the N-glycan on proteins, calnexin was observed to efficiently retain GPI-APs in the ER until they were correctly folded. In addition, sufficient ER retention time was crucial for GPI-inositol deacylation, which is mediated by post-GPI attachment protein 1 (PGAP1). Once the calnexin/calreticulin cycle was disrupted, misfolded and inositol-acylated GPI-APs could not be retained in the ER and were exposed on the plasma membrane. In calnexin/calreticulin-deficient cells, endogenous GPI-anchored alkaline phosphatase was expressed on the cell surface, but its activity was significantly decreased. ER stress induced surface expression of misfolded GPI-APs, but proper GPI-inositol deacylation occurred due to the extended time that they were retained in the ER. Our results indicate that calnexin-mediated ER quality control systems for GPI-APs are necessary for both protein folding and GPI-inositol deacylation.


Assuntos
Calnexina/metabolismo , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Oligossacarídeos/metabolismo , Dobramento de Proteína , Calnexina/genética , Membrana Celular/genética , Retículo Endoplasmático/genética , Células HEK293 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Oligossacarídeos/genética , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo
15.
Acta Oncol ; 60(6): 735-743, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33720799

RESUMO

OBJECTIVES: The positron emission tomography (PET) could predict the prognosis of DLBCL patients, but the exact procedure on interim PET (iPET) to determine chemoresistant patients remains elusive. METHODS: We retrospectively analyzed 593 newly diagnosed DLBCL patients uniformly treated with R-CHOP regimen. Among them, 352 patients diagnosed from August 2010 to December 2016 were included in the test cohort and 241 patients diagnosed from January 2017 to December 2019 were included in the validation cohort. The iPET was evaluated with Deauville criteria and ΔSUVmax method. The reduction of maximal SUV between baseline and after 4 cycles of chemotherapy were defined as ΔSUVmax. The survival functions were depicted using the Kaplan-Meier method and compared with the log-rank test. RESULTS: Patients with iPET Deauville 4 had heterogeneous outcome and end of treatment complete response rates (eCRR). Combined Deauville with ΔSUVmax method, we proposed a modified-Deauville model: patients with Deauville 4 and ΔSUVmax > 70%, as well as those with Deauville 1-3, were reclassified into the modified-Deauville negative group, while patients with Deauville 4 and ΔSUVmax ≤ 70%, as well as those with Deauville 5, into the modified-Deauville positive group. In the test cohort, 3-year PFS, OS and eCRR of modified-Deauville negative group were 80.2%, 89.9% and 91.8%, significantly higher than those of positive group (12.5%, 27.3% and 29.2%, p ≤ .001). Similar results were found in the validation cohort, that 3-year PFS, OS and eCRR were 87.8%, 95.4%, 96.3% in modified-Deauville negative group, and 27.4%, 32.5%, 13.5% in positive group. Through modified-Deauville model, patients in iPET positive group had very low eCRR and were resistant to conventional chemotherapy. CONCLUSIONS: The modified-Deauville model could better distinguish DLBCL patients with poor response to chemotherapy. Accordingly, these patients could be recognized early and provided with alternative therapeutic agents, which might improve the clinical outcome of refractory DLBCL patients.


Assuntos
Linfoma Difuso de Grandes Células B , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Fluordesoxiglucose F18 , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico por imagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Tomografia por Emissão de Pósitrons , Prognóstico , Estudos Retrospectivos
16.
Exp Cell Res ; 386(2): 111740, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31756312

RESUMO

Advanced gastric cancer (GC) is aggressive with a high mortality rate. Rhesus family, C glycoprotein (RhCG) participates in tumor progression in many cancers, however its function in GC is still unknown. Here, we showed that RhCG was overexpressed in GC tissues at mRNA (P = 0.036) and protein levels (P < 0.05) compared with normal tissues. High RhCG level was correlated with poor differentiation (P = 0.037), TNM stage (P < 0.001), high HER-2 level (P = 0.018) and worse prognosis (P < 0.001). Cox proportional hazard model indicated that RhCG level was an independent prognostic biomarker. RhCG knockdown significantly decreased pHi and impeded tumor cellular proliferation, migration and invasion and repressed ß-catenin and c-myc expression in GC cells. Moreover, GC cells with high RhCG level had reduced oxaliplatin efficacy suggesting a role for RhCG as a therapeutic target for GC. Our findings revealed a function of RhCG in cancer pathogenesis, invasion and metastasis in human GC. We suggest that RhCG act may as a novel prognostic indicator and a therapeutic target for gastric adenocarcinoma.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Proteínas de Transporte de Cátions/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , Glicoproteínas de Membrana/genética , Receptor ErbB-2/genética , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Proteínas de Transporte de Cátions/antagonistas & inibidores , Proteínas de Transporte de Cátions/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Metástase Linfática , Masculino , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Oxaliplatina/uso terapêutico , Prognóstico , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais , beta Catenina/genética , beta Catenina/metabolismo
17.
Molecules ; 26(18)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34576938

RESUMO

Glycosylphosphatidylinositol (GPI) anchor modification is a posttranslational modification of proteins that has been conserved in eukaryotes. The biosynthesis and transfer of GPI to proteins are carried out in the endoplasmic reticulum. Attachment of GPI to proteins is mediated by the GPI-transamidase (GPI-TA) complex, which recognizes and cleaves the C-terminal GPI attachment signal of precursor proteins. Then, GPI is transferred to the newly exposed C-terminus of the proteins. GPI-TA consists of five subunits: PIGK, GPAA1, PIGT, PIGS, and PIGU, and the absence of any subunit leads to the loss of activity. Here, we analyzed functionally important residues of the five subunits of GPI-TA by comparing conserved sequences among homologous proteins. In addition, we optimized the purification method for analyzing the structure of GPI-TA. Using purified GPI-TA, preliminary single particle images were obtained. Our results provide guidance for the structural and functional analysis of GPI-TA.


Assuntos
Aciltransferases/química , Aciltransferases/genética , Aciltransferases/metabolismo , Aminoácidos/genética , Aciltransferases/isolamento & purificação , Microscopia Crioeletrônica , Detergentes/química , Células HEK293 , Humanos , Mutação , Conformação Proteica , Subunidades Proteicas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
18.
Cell Struct Funct ; 45(1): 77-92, 2020 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-32404555

RESUMO

Endocytic cargos are transported to recycling endosomes (RE) but how these sorting platforms are generated is not well understood. Here we describe our biochemical and live imaging studies of the conserved MON2-DOPEY complex in RE formation. MON2 mainly co-localized with RE marker RAB4B in peripheral dots and perinuclear region. The peripheral RE approached, interacted with, and separated from sorting nexin 3 (SNX3)-positive early endosomes (EE). Membrane-bound DOPEY2 was recruited to RE dependent upon MON2 expression, and showed binding abilities to kinesin and dynein/dynactin motor proteins. MON2-knockout impaired segregation of RE from EE and led to a decreased tubular recycling endosomal network, whereas RE was accumulated at perinuclear regions in DOPEY2-knockout cells. MON2 depletion also impaired intracellular transferrin receptor recycling, as well as retrograde transport of Wntless during its passage through RE before delivery from EE to the Golgi. Together, these data suggest that the MON2 drives separation of RE from EE and is required for efficient transport of endocytic cargo molecules.Key words: membrane trafficking, MON2, recycling endosomes, Wntless.


Assuntos
Endossomos/metabolismo , Complexo de Golgi/metabolismo , Transporte Proteico/fisiologia , ATPases Translocadoras de Prótons/metabolismo , Endocitose/fisiologia , Humanos , Proteínas de Transporte Vesicular/metabolismo , Rede trans-Golgi/metabolismo
19.
Cancer Sci ; 111(4): 1266-1278, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060966

RESUMO

Succinate dehydrogenase (SDH) deficiency is associated with gastrointestinal stromal tumor (GIST) oncogenesis, but the underlying molecular mechanism remains to be further investigated. Here, we show that succinate accumulation induced by SDHB loss of function increased the expression of zinc finger protein 148 (ZNF148, also named ZBP-89) in GIST cells. Meanwhile, ZNF148 is found to be phosphorylated by ERK at Ser306, and this phosphorylation results in ZNF148 binding to Forkhead box M1 (FOXM1). Through the complex formation at the promoter, ZNF148 facilitates Histone H3 acetylation and FOXM1-mediated Snail transcription, which eventually promotes cell invasion and tumor growth. The clinical analysis indicates that SDHB deficiency is associated with elevated ZNF148 levels, and ZNF148-S306 phosphorylation level displays a positive correlation with poor prognosis in GIST patients. These findings illustrate an unidentified molecular mechanism underlying FOXM1-regulated gene transcription related to GIST cell invasion, which highlights the physiological effects of SDHB deficiency on the invasiveness of GIST.


Assuntos
Proteínas de Ligação a DNA/genética , Proteína Forkhead Box M1/genética , Tumores do Estroma Gastrointestinal/genética , Succinato Desidrogenase/genética , Fatores de Transcrição/genética , Acetilação , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Mutação em Linhagem Germinativa , Xenoenxertos , Histonas/genética , Humanos , Masculino , Camundongos , Intervalo Livre de Progressão , Regiões Promotoras Genéticas/genética , Fatores de Transcrição da Família Snail/genética , Succinato Desidrogenase/deficiência , Transcrição Gênica/genética
20.
Yeast ; 37(7-8): 359-371, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32491201

RESUMO

In the budding yeast Saccharomyces cerevisiae, Svl3 and Pam1 proteins work as functional homologues. Loss of their function causes increased levels of chitin deposition in the cell wall and temperature sensitivity, suggesting their involvement in cell wall formation. We found that the N- and C-termini of these proteins have distinctive and critical functions. They contain an N-terminal part that has a probable 2-dehydropantoate 2-reductase domain. In Svl3, this part can be replaced with the yeast 2-dehydropantoate 2-reductase, Pan5, suggesting that Svl3 and its homologues may be able to mediate 2-dehydropantoate 2-reductase function. On the other hand, Svl3 is recruited to the bud tip and bud neck via multiple localization signals in the C-terminal part. One of such signals is the lysine-rich region located in the C-terminal end. The function and localization of Svl3 are significantly disrupted by the loss of this lysine-rich region; however, its localization is not completely abolished by the mutation because another localization signal enables appropriate transport. Svl3 and Pam1 orthologues are found in cells across fungal species. The Svl3 orthologues of Candida glabrata can complement the loss of Svl3 and Pam1 in S. cerevisiae. C. glabrata cells lacking the SVL3 and PAM1 orthologue genes exhibit phenotypes similar to those observed in svl3∆pam1∆ S. cerevisiae cells. Thus, Svl3 homologues may be generally required for the assembly of the cell wall in fungal cells.


Assuntos
Parede Celular/genética , Parede Celular/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oxirredutases do Álcool , Candida glabrata , Quitina/metabolismo , Genes Fúngicos/genética , Mutação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
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