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1.
Nat Chem Biol ; 20(5): 615-623, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38167916

RESUMEN

Cellular context is crucial for understanding the complex and dynamic kinase functions in health and disease. Systematic dissection of kinase-mediated cellular processes requires rapid and precise stimulation ('pulse') of a kinase of interest, as well as global and in-depth characterization ('chase') of the perturbed proteome under living conditions. Here we developed an optogenetic 'pulse-chase' strategy, termed decaging kinase coupled proteomics (DeKinomics), for proteome-wide profiling of kinase-driven phosphorylation at second-timescale in living cells. We took advantage of the 'gain-of-function' feature of DeKinomics to identify direct kinase substrates and further portrayed the global phosphorylation of understudied receptor tyrosine kinases under native cellular settings. DeKinomics offered a general activation-based strategy to study kinase functions with high specificity and temporal resolution under living conditions.


Asunto(s)
Proteómica , Humanos , Fosforilación , Proteómica/métodos , Proteoma/metabolismo , Optogenética/métodos , Células HEK293
2.
J Proteome Res ; 21(11): 2727-2735, 2022 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-36280823

RESUMEN

Tyrosine phosphorylation (pTyr)-dependent signaling pathways play a vital role in various biological processes, which are spatiotemporally assembled and dynamically regulated on a minute scale by pTyr in living cells. Studying these pTyr-mediated signaling complexes is therefore challenging due to the highly dynamic nature of the protein complexes and the low abundance of pTyr. In this study, we adopted minute-resolution APEX2-based proximity labeling (PL) in living cells and Src SH2 superbinder-based pTyr peptide enrichment for simultaneously profiling these protein complexes and associated pTyr sites from the same affinity-purified sample. Upon different time courses of EGF stimulation of the living cells stably expressing APEX2-FLAG-GRB2, we constructed two-dimensional time-course curves for both interactome and tyrosine phosphoproteome. Well-annotated pTyr signaling complexes in EGFR signaling and located at the endosome were quantified with tightly correlated time-course curves for both interacting proteins and pTyr sites. Importantly, the correlated time-course curves for EGFR and endosomal HGS were well validated by targeted-parallel reaction monitoring (PRM)-MS analysis. Taking advantage of the high sensitivity of the PRM assay, the low-abundant pTyr peptide EGFR pY1110, which cannot be identified in the data-dependent acquisition (DDA) analysis, could be well quantified. Collectively, this two-dimensional proximity proteomic strategy is promising for comprehensively characterizing pTyr-mediated protein complexes with high sensitivity in living cells.


Asunto(s)
Fenómenos Biológicos , Proteómica , Fosfotirosina/metabolismo , Proteómica/métodos , Dominios Homologos src , Fosforilación , Tirosina/metabolismo , Péptidos/metabolismo , Receptores ErbB/metabolismo
3.
Anal Chem ; 94(18): 6799-6808, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35471023

RESUMEN

Protein complexes mediated by various post-translational modifications (PTMs) play important roles in almost every aspect of biological processes. PTM-mediated protein complexes often have weak and transient binding properties, which limit their unbiased profiling especially in complex biological samples. Here, we developed a plug-and-play chemical proteomic approach for high-throughput analyis of PTM-mediated protein complexes. Taking advantage of the glutathione-S-transferase (GST) tag, which is the gold standard for protein purification and has wide access to a variety of proteins of interest (POIs), a glutathione (GSH) group- and photo-cross-linking group-containing trifunctional chemical probe was developed to tag POIs and assembled onto a streptavidin-coated 96-well plate for affinity purification, photo-cross-linking, and proteomics sample preparation in a fully integrated manner. Compared with the previously developed photo-pTyr-scaffold strategy, by assembling the tyrosine phosphorylation (pTyr) binding domain through covalent NHS chemistry, the new plug-and-play strategy using a noncovalent GST-GSH interaction has comparable enrichment efficiency for EGF stimulation-dependent pTyr protein complexes. To further prove its feasibility, we additionally assembled four pTyr-binding domains in the 96-well plate and selectively identified their pTyr-dependent interacting proteins. Importantly, we systematically optimized and applied the plug-and-play approach for exploring protein methylation-mediated protein complexes, which are difficult to be characterized due to their weak binding affinity and the lack of efficient enrichment strategies. We explored a comprehensive protein methylation-mediated interaction network assembled by five protein methylation binding domains including the chromo domain of MPP8, tandem tudor domain of KDM4A, full-length CBX1, PHD domain of RAG2, and tandem tudor domain of TP53BP1 and validated the chromo domain- and tudor domain-mediated interaction with histone H3. Collectively, this plug-and-play approach provides a convenient and generic strategy for exploring PTM-dependent protein complexes for any POIs with the GST tag.


Asunto(s)
Procesamiento Proteico-Postraduccional , Proteómica , Glutatión/metabolismo , Histonas/química , Metilación , Proteómica/métodos
4.
Opt Express ; 30(14): 24481-24496, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-36237002

RESUMEN

To meet the need for rapid, high-precision, and non-contact measurement of the radius of curvature (ROC) for large quantities of spherical optics, a radius measurement method based on transverse dual differential confocal (TDDC) detection is proposed in this study. First, a template S0 with a known ROC, R0, is axially scanned on its confocal position to obtain the fitted linear function lTDDC(z) using TDDC. Second, the template S0 is replaced by Sn, which is one of the test sample in large quantities, then the single point TDDC intensity ITDDC(Δzn) is captured without scan, which will be applied to obtain the defocus Δzn according to the linear function lTDDC(z). Finally, the ROC Rn under test is calculated using Δzn and R0. Simulation and experiments show that the measurement accuracy can achieve 8.0 ppm, and the measurement efficiency is 60 times higher than that of the traditional differential confocal scanning measurement. Measurement based on TDDC only requires scanning once and replacing Sn N times to realize the fast, high-precision, non-contact ROC detection of N pieces of spherical optics, which enables the high-efficiency and high-precision measurement of large quantities of spherical optics.

5.
Ophthalmic Res ; 65(3): 293-299, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-32353847

RESUMEN

PURPOSE: The aim of this study was to compare the prevalence of diabetic retinopathy (DR) and diabetic macular edema (DME), as well as their risk factors in patients with early-onset diabetes (EOD, ≤40 years) and late-onset diabetes (LOD, >40 years). METHODS: Patients were recruited from a community-based study, Fushun Diabetic Retinopathy Cohort Study (FS-DIRECT), conducted between July 2012 and May 2013 in China. The presence and severity of DR and DME were determined by a modified Early Treatment Diabetic Retinopathy Study (ETDRS) retinopathy scale of six-field fundus photographs. RESULTS: A total of 1,932 patients (796 male, 41.2%) with gradable fundus photography were included. The prevalence of any DR and DME was 67.0% (95% confidence interval [CI]: 60.3-73.7%) and 39.3% (95% CI: 32.1-46.5%) in the EOD patients, respectively, which were both significantly higher than that in the LOD patients (DR: 41.9%, 39.6-44.2%, p < 0.001; DME: 14.4%, 12.7-16.1%, p < 0.001). Insulin use was associated with both the presence of DR and DME in both EOD and LOD patients. Besides insulin use, a high level of income (odds ratio [OR], 95% CI: 0.05, 0.01-0.51) was negatively associated with DR, and higher high-density lipoprotein (OR, 95% CI: 4.14, 1.44-11.91) was associated with DME among EOD patients. CONCLUSION: In this sample of patients with type 2 diabetes, both prevalence of DR and DME were apparently higher in patients who developed diabetes ≤40 years of age than those who developed it later.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Insulinas , Edema Macular , Estudios de Cohortes , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Retinopatía Diabética/complicaciones , Retinopatía Diabética/diagnóstico , Retinopatía Diabética/epidemiología , Humanos , Edema Macular/diagnóstico , Edema Macular/epidemiología , Edema Macular/etiología , Masculino , Prevalencia , Factores de Riesgo
6.
J Proteome Res ; 20(7): 3709-3719, 2021 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-34134489

RESUMEN

The epidermal growth factor receptor (EGFR) signal modulates cell proliferation, migration, and survival. Aberrant activation of EGFR constitutes the major cause of various cancers. Receptor ubiquitination and degradation mediated by CBL proteins play negative regulatory roles and control the intensity and duration of the signaling. With the construction of stable cell lines inducibly expressing FLAG-tagged CBL or CBLB, we identified 102 and 82 stable interacting proteins of CBL and CBLB, respectively, through the affinity purification followed by mass spectrometry (AP-MS) approach. Time-resolved profiling at six different time points combined with functional annotations of the temporal interactomes provides insights into the dynamic assembly of signal proteins upon EGFR signaling activation. Comparison between the interactomes of CBL and CBLB indicates their redundant but also complementary functions. Importantly, we validated the stable association of EPS15L1 and ITSN2 and temporal association of TNK2 to both CBL and CBLB through biochemical assays. Collectively, these results offer a useful resource for CBL and CBLB interactomes and highlight their prominent and diverse roles in the EGFR signaling network.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Factor de Crecimiento Epidérmico , Proteínas Proto-Oncogénicas c-cbl , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras del Transporte Vesicular , Línea Celular , Factor de Crecimiento Epidérmico/metabolismo , Humanos , Proteínas Tirosina Quinasas , Proteínas Proto-Oncogénicas c-cbl/genética , Proteínas Proto-Oncogénicas c-cbl/metabolismo , Transducción de Señal , Ubiquitinación
7.
Anal Chem ; 93(5): 3026-3034, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33522225

RESUMEN

Affinity purification coupled to mass spectrometry (AP-MS) is a popular approach for deciphering the architecture of protein interaction networks. Protein lysates (100 µg) are typically required for multistep sample processing in large volumes, which often causes sample loss and reduces the MS analysis sensitivity. Herein, we reported a fully integrated spintip-based AP-MS technology, termed FISAP, for multiplexed and sensitive interactome profiling. The FISAP device can be easily employed for routine use by introducing AP beads into a C18 StageTip. Taking advantage of the switchable functionalization of the C18 matrix by sodium dodecyl sulfate, all the sample preparation steps encompassing peptide or antibody-based AP, reduction, alkylation, tryptic digestion, tandem mass tag (TMT) labeling, and desalting can be performed in a single tip with a benchtop centrifuge in 4 h. Using a biotinylated tyrosine phosphorylated (pTyr) peptide as an affinity ligand, we mapped the pTyr-dependent interactome of the pY191 motif on the immune receptor CD28 cytoplasmic domain. When processing 50 µg of protein lysates, FISAP showed a comparable interactome identification performance but better quantification performance and lower background interference compared to the traditional tube-based method. Furthermore, a cost-effective on-column TMT labeling protocol was established and integrated into the FISAP pipeline with increased sensitivity. Compared to the tube-based method, the usage of a synthetic peptide probe and a TMT reagent was both reduced by 20 times. As low as 1 µg of protein lysates could be applied for interactome profiling. Finally, we expanded the applicability of the FISAP technology to epitope tag-based AP-MS for profiling the ILK/PINCH/Parvin complex using 100 times less protein lysate than a previous report. Collectively, FISAP is an easy-to-use and sensitive technology for quantitatively profiling protein complexes when the starting material and affinity reagent are the limitation, especially for applications in biomedical research and chemical biology.


Asunto(s)
Proteínas , Proteómica , Espectrometría de Masas , Manejo de Especímenes , Tecnología
8.
Ophthalmic Res ; 64(5): 857-862, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32759608

RESUMEN

OBJECTIVES: This study aimed to assess the association between the corneal biomechanical parameters and visual field (VF) loss in patients with asymmetric primary open-angle glaucoma (POAG). METHODS: A total of 89 POAG patients (50 males, 56.2%) with asymmetric VF loss, aged 65.2 ± 13.3 years, were enrolled in this study. Asymmetric VF loss was defined as an interocular difference of the global index mean deviation (MD) >2 dB. Intraocular pressure (IOP), central corneal thickness (CCT), and corneal biomechanical parameters such as maximum amplitude at the apex of highest concavity (def ampl HC) were measured. The worse eye was defined as the eye with a smaller MD. RESULTS: The worse eyes had lower MD (-11.9 ± 6.7 dB vs. -5.3 ± 5.0 dB; p < 0.001) and higher IOP (14.6 ± 3.3 vs.13.9 ± 2.6 mm Hg, p = 0.04) than the better eyes. There was no significant difference between the 2 groups for CCT. The interocular difference of MD (IDMD) was negatively correlated with the interocular difference of IOP (r = -0.22, p = 0.04), while positively correlated with the interocular difference of def ampl HC (r = 0.27, p = 0.01). In patients with moderate asymmetric VF loss (IDMD ≥6 dB), def ampl HC of the worse eyes group (1.07 ± 0.12 mm) was significantly lower than the better eyes group (1.10 ± 0.11 mm, p = 0.02). CONCLUSION: Asymmetric POAG was associated with asymmetry in IOP and corneal biomechanical parameters but not in CCT. Lower deflection amplitude and higher IOP were found in eyes with more severe VF damage in POAG patients.


Asunto(s)
Glaucoma de Ángulo Abierto , Anciano , Córnea , Femenino , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Tonometría Ocular , Trastornos de la Visión , Pruebas del Campo Visual , Campos Visuales
9.
Anal Chem ; 92(13): 8893-8900, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32490667

RESUMEN

With recent advances in LC-MS systems, current MS-based proteomics has an increasing need for automated, high-throughput sample preparation with neglectable sample loss. In this study, we developed a microfluidic system for fully automated proteomics sample preparation. All of the required proteomics sample preparation steps for both protein digestion and peptide fractionation are fully integrated into a disposable plastic chip device (named AutoProteome Chip). The AutoProteome Chip packed with mixed-mode ion exchange beads and C18 membrane in tandem could be fabricated with very low cost and high stability in organic reagents. Benefiting from its low backpressure, the AutoProteome Chip could be precisely driven by gas pressure, which could be easily multiplexed. As low as 2 ng of standard protein BSA could be trapped into the AutoProteome chip and processed within 2 h. Fully automated processing of 10 µg of protein extracts of HEK 293T cells achieved more than 97% of digestion efficiency with missed cleavage less than 2 and comparable performance with conventional approaches. More than 4700 proteins could be readily identified within 80 min of LC-MS analysis with good label-free quantification performance (Pearson correlation coefficient >0.99). Furthermore, deep proteome profiling by integrated high-pH RP fractionation in the same AutoProteome Chip resulted in more than 7500 proteins being identified from only 20 µg of protein extracts of HEK 293T cells and comparable reprodicibility as single-shot analysis. The AutoProteome Chip system provided a valuable prototype for developing a fully automated proteome analysis workflow and for proteomic applications with high demand for processing throughput, reproducibility, and sensitivity.


Asunto(s)
Péptidos/análisis , Proteómica/métodos , Animales , Bovinos , Cromatografía Líquida de Alta Presión , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno , Dispositivos Laboratorio en un Chip , Proteómica/instrumentación , Albúmina Sérica Bovina/análisis , Albúmina Sérica Bovina/metabolismo , Espectrometría de Masas en Tándem
10.
Anal Chem ; 92(13): 8933-8942, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32539344

RESUMEN

Phosphotyrosine (pTyr) signaling complexes are important resources of biomarkers and drug targets which often need to be profiled with enough throughput. Current profiling approaches are not feasible to meet this need due to either biased profiling by antibody-based detection or low throughput by traditional affinity purification-mass spectrometry approach (AP-MS), as exemplified by our previously developed photo-pTyr-scaffold approach. To address these limitations, we developed a 96-well microplate-based sample preparation and fast data independent proteomic analysis workflow. By assembling the photo-pTyr-scaffold probe into a 96-well microplate, we achieved steric hindrance-free photoaffinity capture of pTyr signaling complexes, selective enrichment under denaturing conditions, and efficient in-well digestion in a fully integrated manner. EGFR signaling complex proteins could be efficiently captured and identified by using 300 times less cell lysate and 100 times less photo-pTyr-scaffold probe as compared with our previous approach operated in an Eppendorf tube. Furthermore, the lifetime of the photo-pTyr-scaffold probe in a 96-well microplate was significantly extended from 1 week up to 1 month. More importantly, by combining with high-flow nano LC separation and data independent acquisition on the Q Exactive HF-X mass spectrometer, LC-MS time could be significantly reduced to only 35 min per sample without increasing sample loading amount and compromising identification and quantification performance. This new high-throughput proteomic approach allowed us to rapidly and reproducibly profile dynamic pTyr signaling complexes with EGF stimulation at five time points and EGFR inhibitor treatment at five different concentrations. We are therefore optimized for its generic application in biomarkers discovery and drug screening in a high-throughput fashion.


Asunto(s)
Fosfotirosina/análisis , Proteómica/métodos , Cromatografía Líquida de Alta Presión , Factor de Crecimiento Epidérmico/farmacología , Receptores ErbB/metabolismo , Células HeLa , Humanos , Espectrometría de Masas , Fosfotirosina/metabolismo , Análisis por Matrices de Proteínas , Proteoma/efectos de los fármacos , Proteoma/metabolismo , Transducción de Señal
11.
Anal Chem ; 91(15): 10026-10032, 2019 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-31282657

RESUMEN

Low-abundance phosphotyrosine (pTyr)-mediated signaling protein complexes play critical roles in cancer signaling. The precise and comprehensive profiling of these pTyr-mediated protein complexes remains challenging because of their dynamic nature and weak binding affinity. Taking advantage of the SH2 domains modified with trifunctional chemical probes and genetic mutations (termed Photo-pTyr-scaffold), we developed a Photo-pTyr-scaffold-based forward-phase protein array that can be used to specifically capture complexes by developing an engineered SH2 domain, photoaffinity cross-linking, and antibody-based measuring weak pTyr-mediated protein complexes from complex biological samples in a 96-well microplate format. This platform demonstrated good precision for quantitation (R2 = 0.99) and high sensitivity by which only 5 µg of whole cell lysates is needed. We successfully applied the technology for profiling the dynamic EGF-stimulation-dependent EGFR signaling protein complexes across four different time courses (i.e., 0, 2, 5, 10, and 30 min) in a high-throughput manner. We further evaluated the modulation of EGFR-GRB2-SHC1 protein complexes by FDA-approved EGFR kinase inhibitor erlotinib, demonstrating the feasibility of this approach for high-throughput drug screening. The Photo-pTyr-scaffold-based forward-phase protein array could be generically applicable for exploring the dynamic pTyr signaling complexes in various biological systems and screening for related drugs in a high-throughput manner.


Asunto(s)
Fosfotirosina/metabolismo , Análisis por Matrices de Proteínas/métodos , Rayos Ultravioleta , Línea Celular Tumoral , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Clorhidrato de Erlotinib/química , Clorhidrato de Erlotinib/metabolismo , Clorhidrato de Erlotinib/farmacología , Proteína Adaptadora GRB2/química , Proteína Adaptadora GRB2/metabolismo , Ensayos Analíticos de Alto Rendimiento , Humanos , Fosfotirosina/química , Unión Proteica , Transducción de Señal/efectos de los fármacos , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/química , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src/metabolismo , Dominios Homologos src
12.
Anal Chem ; 90(21): 12574-12583, 2018 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-30280895

RESUMEN

Proteins often assemble into multiprotein complexes for carrying out their biological functions. Affinity purification combined with mass spectrometry (AP-MS) is a method of choice for unbiasedly charting protein complexes. Typically, genetically tagged bait protein and associated proteins are immunoprecipitated from cell lysate and subjected to in-gel or on-bead digestion for MS analysis. However, the sample preparation procedures are often time-consuming and skipping reduction and alkylation steps results in incomplete digestion. Here, by seamlessly combining AP with the simple and integrated spintip-based proteomics technology (SISPROT), we developed an integrated AP-MS workflow for simultaneously processing more than 10 AP samples from cells cultured in six-well plates in 2 h. Moreover, we developed a quantitation-based data analysis workflow for differentiating potential interacting proteins from nonspecific interferences. The AP-SISPROT ensures high digestion efficiency especially for large transmembrane proteins such as EGFR and high quantification precision for profiling temporal interaction network of key EGFR signaling protein GRB2 across four time points of EGF treatment. More importantly, the integration feature allows minimum sample lose and helps the development of an ideal AP-MS workflow for studying endogenous protein complexes by the CRISPR Cas9 technology for the first time. By generating endogenously expressed bait protein fused with affinity tag, protein complexes associated with endogenous Integrin-linked kinase (ILK) was identified with much higher selectivity as compared with overexpressed and tagged ILK. The AP-SISPROT technology and its combination with CRISPR Cas9 technology should be generally applicable for studying protein complexes in a more efficient and physiologically relevant manner.


Asunto(s)
Cromatografía de Afinidad/métodos , Espectrometría de Masas/métodos , Complejos Multiproteicos/análisis , Proteoma/análisis , Proteómica/métodos , Sistemas CRISPR-Cas , Células HEK293 , Células HeLa , Humanos , Complejos Multiproteicos/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo
13.
Anal Chem ; 88(9): 4864-71, 2016 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-27062885

RESUMEN

Great efforts have been taken for developing high-sensitive mass spectrometry (MS)-based proteomic technologies, among which sample preparation is one of the major focus. Here, a simple and integrated spintip-based proteomics technology (SISPROT) consisting of strong cation exchange beads and C18 disk in one pipet tip was developed. Both proteomics sample preparation steps, including protein preconcentration, reduction, alkylation, and digestion, and reversed phase (RP)-based desalting and high-pH RP-based peptide fractionation can be achieved in a fully integrated manner for the first time. This easy-to-use technology achieved high sensitivity with negligible sample loss. Proteomic analysis of 2000 HEK 293 cells readily identified 1270 proteins within 1.4 h of MS time, while 7826 proteins were identified when 100000 cells were processed and analyzed within only 22 h of MS time. More importantly, the SISPROT can be easily multiplexed on a standard centrifuge with good reproducibility (Pearson correlation coefficient > 0.98) for both single-shot analysis and deep proteome profiling with five-step high-pH RP fractionation. The SISPROT was exemplified by the triplicate analysis of 100000 stem cells from human exfoliated deciduous teeth (SHED). This led to the identification of 9078 proteins containing 3771 annotated membrane proteins, which was the largest proteome data set for dental stem cells reported to date. We expect that the SISPROT will be well suited for deep proteome profiling for fewer than 100000 cells and applied for translational studies where multiplexed technology with good label-free quantification precision is required.


Asunto(s)
Proteoma/análisis , Células Madre/química , Células HEK293 , Humanos , Espectrometría de Masas , Células Madre/patología , Exfoliación Dental/patología , Diente Primario/patología
14.
Adv Exp Med Biol ; 919: 345-382, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27975226

RESUMEN

Posttranslational modifications (PTMs) are important biochemical processes for regulating various signaling pathways and determining specific cell fate. Mass spectrometry (MS)-based proteomics has been developed extensively in the past decade and is becoming the standard approach for systematic characterization of different PTMs on a global scale. In this chapter, we will explain the biological importance of various PTMs, summarize key innovations in PTMs enrichment strategies, high-performance liquid chromatography (HPLC)-based fractionation approaches, mass spectrometry detection methods, and lastly bioinformatic tools for PTMs related data analysis. With great effort in recent years by the proteomics community, highly efficient enriching methods and comprehensive resources have been developed. This chapter will specifically focus on five major types of PTMs; phosphorylation, glycosylation, ubiquitination/sumosylation, acetylation, and methylation.


Asunto(s)
Biología Computacional/métodos , Minería de Datos/métodos , Bases de Datos de Proteínas , Espectrometría de Masas/métodos , Procesamiento Proteico-Postraduccional , Proteínas/análisis , Proteoma , Proteómica/métodos , Acetilación , Algoritmos , Animales , Glicosilación , Ensayos Analíticos de Alto Rendimiento , Humanos , Metilación , Fosforilación , Reproducibilidad de los Resultados , Programas Informáticos , Ubiquitinación
15.
Se Pu ; 42(7): 693-701, 2024 Jul.
Artículo en Zh | MEDLINE | ID: mdl-38966977

RESUMEN

Tyrosine phosphorylation, a common post-translational modification process for proteins, is involved in a variety of biological processes. However, the abundance of tyrosine-phosphorylated proteins is very low, making their identification by mass spectrometry (MS) is difficult; thus, milligrams of the starting material are often required for their enrichment. For example, tyrosine phosphorylation plays an important role in T cell signal transduction. However, the number of primary T cells derived from biological tissue samples is very small, and these cells are difficult to culture and expand; thus, the study of T cell signal transduction is usually carried out on immortalized cell lines, which can be greatly expanded. However, the data from immortalized cell lines cannot fully mimic the signal transduction processes observed in the real physiological state, and they usually lead to conclusions that are quite different from those of primary T cells. Therefore, a highly sensitive proteomic method was developed for studying tyrosine phosphorylation modification signals in primary T cells. To address the issue of the limited T cells numbers, a comprehensive protocol was first optimized for the isolation, activation, and expansion of primary T cells from mouse spleen. CD3+ primary T cells were successfully sorted; more than 91% of the T cells collected were well activated on day 2, and the number of T cells expanded to over 7-fold on day 4. Next, to address the low abundance of tyrosine-phosphorylated proteins, we used SH2-superbinder affinity enrichment and immobilized Ti4+affinity chromatography (Ti4+-IMAC) to enrich the tyrosine-phosphorylated polypeptides of primary T cells that were co-stimulated with anti-CD3 and anti-CD28. These polypeptides were resolved using nanoscale liquid chromatography-tandem mass spectrometry (nanoLC-MS/MS). Finally, 282 tyrosine phosphorylation sites were successfully identified in 1 mg of protein, including many tyrosine phosphorylation sites on the immunoreceptor tyrosine-based activation motif (ITAM) in the intracellular region of the T cell receptor membrane protein CD3, as well as the phosphotyrosine sites of ZAP70, LAT, VAV1, and other proteins related to signal transduction under costimulatory conditions. In summary, to solve the technical problems of the limited number of primary cells, low abundance of tyrosine-phosphorylated proteins, and difficulty of detection by MS, we developed a comprehensive proteomic method for the in-depth analysis of tyrosine phosphorylation modification signals in primary T cells. This protocol may be applied to map signal transduction networks that are closely related to physiological states.


Asunto(s)
Fosfoproteínas , Proteoma , Linfocitos T , Tirosina , Animales , Ratones , Fosforilación , Fosfoproteínas/análisis , Proteoma/análisis , Proteómica/métodos , Transducción de Señal
16.
Mol Genet Genomic Med ; 12(4): e2439, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38613222

RESUMEN

OBJECTIVE: To characterize the phenotype spectrum, diagnosis, and response to growth-promoting therapy in patients with ACAN variants causing familial short stature. METHODS: Three families with ACAN variants causing short stature were reported. Similar cases in the literature were summarized, and the genotype and phenotype were analyzed. RESULTS: Three novel heterozygous variants, c.757+1G>A, (splicing), c.6229delG, p.(Asp2078Tfs*1), and c.6679C>T, p.(Gln2227*) in the ACAN gene were identified. A total of 314 individuals with heterozygous variants from 105 families and 8 individuals with homozygous variants from 4 families were confirmed to have ACAN variants from literature and our 3 cases. Including our 3 cases, the variants reported comprised 33 frameshift, 39 missense, 23 nonsense, 5 splicing, 4 deletion, and 1 translocation variants. Variation points are scattered throughout the gene, while exons 12, 15, and 10 were most common (25/105, 11/105, and 10/105, respectively). Some identical variants existing in different families could be hot variants, c.532A>T, p.(Asn178Tyr), c.1411C>T, p.(Gln471*), c.1608C>A, p.(Tyr536*), c.2026+1G>A, (splicing), and c.7276G>T, p.(Glu2426*). Short stature, early-onset osteoarthritis, brachydactyly, midfacial hypoplasia, and early growth cessation were the common phenotypic features. The 48 children who received rhGH (and GnRHa) treatment had a significant height improvement compared with before (-2.18 ± 1.06 SD vs. -2.69 ± 0.95 SD, p < 0.001). The heights of children who received rhGH (and GnRHa) treatment were significantly improved compared with those of untreated adults (-2.20 ± 1.10 SD vs. -3.24 ± 1.14 SD, p < 0.001). CONCLUSION: Our study achieves a new understanding of the phenotypic spectrum, diagnosis, and management of individuals with ACAN variants. No clear genotype-phenotype relationship of patients with ACAN variants was found. Gene sequencing is necessary to diagnose ACAN variants that cause short stature. In general, appropriate rhGH and/or GnRHa therapy can improve the adult height of affected pediatric patients caused by ACAN variants.


Asunto(s)
Enanismo , Hormona de Crecimiento Humana , Adulto , Niño , Humanos , Agrecanos , Genotipo , Heterocigoto , Homocigoto , Pacientes , Fenotipo
17.
Light Sci Appl ; 12(1): 129, 2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37248287

RESUMEN

Raman and Brillouin scattering are sensitive approaches to detect chemical composition and mechanical elasticity pathology of cells in cancer development and their medical treatment researches. The application is, however, suffering from the lack of ability to synchronously acquire the scattering signals following three-dimensional (3D) cell morphology with reasonable spatial resolution and signal-to-noise ratio. Herein, we propose a divided-aperture laser differential confocal 3D Geometry-Raman-Brillouin microscopic detection technology, by which reflection, Raman, and Brillouin scattering signals are simultaneously in situ collected in real time with an axial focusing accuracy up to 1 nm, in the height range of 200 µm. The divided aperture improves the anti-noise capability of the system, and the noise influence depth of Raman detection reduces by 35.4%, and the Brillouin extinction ratio increases by 22 dB. A high-precision multichannel microspectroscopic system containing these functions is developed, which is utilized to study gastric cancer tissue. As a result, a 25% reduction of collagen concentration, 42% increase of DNA substances, 17% and 9% decrease in viscosity and elasticity are finely resolved from the 3D mappings. These findings indicate that our system can be a powerful tool to study cancer development new therapies at the sub-cell level.

18.
Int J Ophthalmol ; 16(2): 260-266, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36816225

RESUMEN

AIM: To estimate and compare the incidence and characteristics of rhegmatogenous retinal detachments (RRDs) in the Wenzhou area in 2015 to 2019. METHODS: All newly developed RRD cases among residents of the Wenzhou area, from January 2015 to December 2019, were retrospectively retrieved from hospital records. Annual population data were extracted from the Wenzhou Statistical Yearbook. RESULTS: There were 3629 eligible cases. The average incidence of RRD was 7.79 cases per 100 000 population (95% confidence interval, 7.24-8.34), and the incidences were 7.99 and 7.56 for males and females, respectively. The annual incidence increased gradually from 7.26 cases per 100 000 in 2015 to 10.00 cases per 100 000 in 2019, with an overall increase of 37.74%. The highest rate of increase occurred in the age group from 60 to 69 years. Of 2750 eyes with axial length (AL) data, 1675 (60.91%) had an AL greater than 24 mm. CONCLUSION: A trend to increasing RRD incidence is observed in the Wenzhou area over the past 5-year period.

19.
Front Oncol ; 12: 868726, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35720012

RESUMEN

Objective: Cancer-associated mesenchymal stem cells (MSCs) regulate the progression of cancers through exosome-delivered components, while few studies are conducted on hepatocellular carcinoma (HCC). This study aimed to evaluate the effect of exosomes from HCC-associated MSCs (HCC-MSCs) on HCC cellular functions and the potential regulatory mechanism. Methods: HCC cells (Huh7 and PLC) were cultured normally or co-cultured with HCC-MSCs, HCC-MSCs plus GW4869, or HCC-MSC-derived exosomes; then mRNA sequencing and RT-qPCR validation were conducted. Subsequently, candidate genes were sorted out and modified in HCC cells. Next, TMBIM6-modified HCC-MSCs were used to treat HCC cells. Results: Both HCC-MSCs and their derived exosomes promoted proliferation, invasion, sphere formation ability but suppressed apoptosis in HCC cells (all p < 0.05); however, the effect of HCC-MSCs on these cellular functions was repressed by exosome inhibitor (GW4869). Subsequently, TMBIM6, EEF2, and PRDX1 were sorted out by mRNA sequencing and RT-qPCR validation as candidate genes implicated in the regulation of HCC cellular functions by HCC-MSC-derived exosomes. Among them, TMBIM6 had a potent effect (all p < 0.05), while EEF2 and PRDX1 had less effect on regulating HCC cell viability and invasion. Next, direct silencing TMBIM6 repressed viability, sphere formation, invasion, epithelial-mesenchymal transition (EMT), and PI3K/AKT pathway but promoted apoptosis in HCC cells; however, overexpressing TMBIM6 showed the opposite effect. Furthermore, incubating with exosomes from TMBIM6-modified HCC-MSCs presented a similar effect as direct TMBIM6 modification in HCC cells. Conclusion: HCC-MSC-derived exosomes transmit TMBIM6 to promote malignant behavior via PI3K/AKT pathway in HCC.

20.
Int J Ophthalmol ; 15(9): 1496-1501, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36124201

RESUMEN

AIM: To evaluate the role of internal limiting membrane (ILM) peeling in preventing secondary epiretinal membrane (ERM) formation in pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR). METHODS: This retrospective study analyzed the medical records of patients who underwent PPV for PDR and were followed up for minimum 3mo. ILM peeling was performed based on the intraoperative surgeons' judgments. ERM was assessed by optical coherence tomography photography. The relationship between ILM peeling and postoperative ERM was analyzed. RESULTS: In total, 212 eyes from 197 patients were included in this study. The incidence of secondary ERM in the ILM non-peeling group was significantly higher than that in the ILM peeling group (37.0% vs 14.0%; P<0.001). Multivariate logistical regression revealed that ILM peeling was highly associated with the prevention of secondary ERM development [odds ratio 0.38; 95% confidence interval 0.17-0.86; P<0.05]. CONCLUSION: ILM peeling during PPV for PDRs can effectively reduce the incidence of secondary ERM development and is worth consideration by vitreoretinal surgeons.

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