An efficient in-gel digestion method on a small amounts of protein sample
Ontology highlight
ABSTRACT:
ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)
SUBMITTER: Keiko Kuwata
PROVIDER: PXD024071 | JPOST Repository | Thu Feb 09 00:00:00 GMT 2023
REPOSITORIES: jPOST
Dataset's files
Items per page: 5 1 - 5 of 20 |
Similar Datasets
Project description:The success of shotgun proteomic analysis depends largely on how samples are prepared. Current approaches such as gel-, solution- or filter-based, although being extensively employed in the field, are time-consuming and less effective with respect to the repetitive sample processing, recovery, and overall yield. As an alternative, suspension trapping (S-Trap) filter is commercially available very recently in the format of single or 96-well filter plate. In contrast to conventional filter aided sample preparation (FASP) approach, which utilizes a molecular weight cutoff (MWCO) membrane as the filter and requires hours of processing before digestion-ready proteins can be obtained, S-Trap employs a three-dimensional porous material as filter media, and traps particulate protein suspension with subsequent depletion of interfering substances and in-filter digestion. Due to the large (sub-micron) pore size, each centrifugation cycle of S-Trap filter only takes around 1 minute, which significantly reduces the total processing time from approximately 3 hours by FASP to less than 15 minutes, suggesting an ultrafast sample preparation approach for shotgun proteomics. Here, for the first time, we comprehensively evaluate the performance of individual S-Trap filter and 96-well filter plate in the context of global protein identification and quantitation using whole cell lysate and clinically relevant sputum samples.
2019-03-28 | PXD010237 | Pride
Project description:Proteomic analysis by combining PAGE separation, gel slicing and slice-by-slice LC-MS/MS has been frequently reported in recent years. Since the MS analysis would provide identities and quantities of the proteins along the whole lane, visualization by dye staining could be skipped to save time and labor and also in some reports assumed to improve MS identification and sensitivity. In this work, we examined the effect of CBB R-250 staining on the performance of the method and the results showed actually better results were obtained with CBB staining than without. A primary examination was firstly performed with gel bands of purified proteins, in which eight protein bands were excised, each from both the CBB-stained and unstained gel parts, and then analyzed by in-gel digestion and quantitative LC-MS/MS. Almost all the proteins were detected with higher sequence coverages and quantities from the stained gel bands than from the unstained. Then a proteomic sample of rat heart soluble proteins was examined for the complete workflow. The sample was firstly separated by nondenaturing PAGE and the gel was divided to two halves, with one CBB-stained and the other unstained. Laboratory-made tools were used to simultaneously cut duplicate lanes from each gel half and then slice each lane into about 39 pieces of the same size (1.1 mm 椋?1.1 mm 椋?1 mm thick). All the gel square pieces were analyzed in standardized procedures of in-gel digestion, peptide extraction and label-free quantitative LC-MS/MS. The results showed an average of 1434 proteins were detected in CBB-stained lanes, 40% higher than the 1013 in unstained lanes. When proteins detected in both conditions were compared, most of them were detected in higher quantities and in more gel squares with CBB staining. The comparison was also performed for SDS-PAGE and similarly advantageous results were obtained from the CBB-stained lanes, in both the detected numbers of proteins and peptides and the detected quantities and square numbers of individual proteins. The data also showed the proteins with lower molecular masses (e.g. < 30 kDa) were more benefited by the staining, probably because the dye binding helped to retain the proteins in gel matrix. In short, though dye staining is no longer a requisite when PAGE separation is followed by whole-gel LC-MS/MS analysis, CBB staining is still recommended for the better detection in proteomic analysis. All the raw and search files of the LC-MS/MS analysis, for (8*4=) 32 gel squares of HMW and LMW markers and (39*4+41*4=) 320 squares of rat heart soluble proteins (totally 704 files), as well as the gel patterns (2 files) and the summaries of the protein-level search results (3 files), are deposited in this project.
2019-02-16 | PXD011689 | Pride
Project description:A human plasma sample was subjected to non-denaturing micro 2-DE and a gel area (5 mm X 18 mm) which includes high-density lipoprotein (HDL) was cut into 1 mm X 1 mm squares, then the proteins in the 90 gel pieces were analyzed by in-gel trypsin digestion and nano-LC-MS/MS. Grid-cutting of the gel was employed to; 1) ensure the total analysis of the proteins in the area, 2) standardize the conditions of analysis by LC-MS/MS, 3) reconstruct the protein distribution patterns from the label-free quantification data. Totally 154 proteins (excluding keratins) were assigned in the 90 gel pieces and the quantity distribution of each was reconstructed as a color density pattern (a native protein map). The map of apolipoprotein (Apo) A-I showed a wide apparent mass distribution characteristic to HDL and was compared with the maps of the other 153 proteins. Eleven proteins showed maps of wide distribution that overlapped with the map of Apo A-I, and all have been reported to be the components of HDL. Further, seven minor proteins associated with HDL were detected at the gel positions of high Apo A-I quantity. These results for the first time visualized the localization of HDL apolipoproteins on a non-denaturing 2-DE gel and strongly suggested their interactions.
2014-04-07 | PXD000852 | Pride
Project description:Clinical biomarkers identified by shotgun proteomics require proteins in body fluids or tissues to be enzymatically digested before being separated and sequenced by Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS). How well peptide signals can be resolved and detected is largely dependent on the quality of sample preparation. Conventional approaches such as in-gel, in-solution, and filter-based digestion, despite their extensive implementation by the community, become less appealing due to their unsatisfying protein/peptide recovery rate, lengthy sample processing, and/or less cost-effectiveness. Suspension Trapping has recently been demonstrated as an ultrafast approach for proteomics analysis. Here, for the first time, we extend its application to human salivary proteome analyses. In particular, we present a simple self-assembled glass fiber filter device, which can be packed with minimal difficulty, is extremely cost-effective and maintains the same performances as commercial filters. As a proof-of-principle, we analyzed the whole saliva from 8 healthy individuals as well as a cohort of 10 subjects of oral squamous cell carcinoma (OSCC) patients and non-OSCC subjects. Label-free quantification revealed surprisingly low inter-individual variability, and identified several known markers. Our study provides the first evidence of an easy-to-use and nearly cost-free device for clinical proteomics as well as for general proteome sample preparation.
2019-03-12 | PXD012436 | Pride
Project description:Using cell sorting technique, we collected Arabidopsis root hair protoplasts (transgenic line harboring root hair specific gene promoter ::GFP, here named GFP) and nonGFP protoplasts( whole root except root hair). Then, we extracted total proteins and RNA for proteome and RNASeq. RNAseq data have already been deposited into NCBI (accession numbers SRR364677 and SRR364678). Total proteins were separated by 1D SDS-PAGE, followed by gel slicing, in gel digested and run ESI-LC-MS/MS on LTQ Orbitrap Velos. We set two biological repeats and each sample was scanned two times (two technique repeats). We then combined all ms/ms raw data from all fractions and technique repeats from one biological sample into one file to indentify proteins by searching Arabidopsis protein database with software Proteome Discoverer (with two searching engines mascot and sequester). Protocol: Protoplasts from EXP7 and non-GFP protoplastswere stored at -80°C, thawed on ice for 5 min, vortexed several times and suspended in 5 x volume of pre-cooled acetone (-20°C) containing 10% (v/v) trichloroacetic acid (TCA) and 0.07% (v/v) 2-mercaptoethanol. Proteins were then precipitated for 2 h at −20°C after thorough mixing. Proteins were collected by centrifuging at 35,000 g (JA-20 108 rotor, Beckman J2-HS) at 4°C for 30 min. The supernatant was removed and the protein pellets were washed three times with cold acetone containing 0.07% (v/v) 2-mercaptoethanol and 1 mMphenylmethanesulfonylfluoride. Protein pellets were dried by lyophilization and stored at -80°C, or immediately extracted using Laemmli buffer (63 mM TrisHCl pH 6.8, 10% glycerol, 2% SDS, 0.0025% bromophenol blue). Protein concentration was determined using Pierce protein assay kit (Pierce, Rockford). Proteins from each sample were separated using a Bis-Tris precast gradient gel (4−16%, Bio-Rad) according to the manufacturer’s instructions. After electrophoresis, the gel was Coomassie-stained using the Colloidal Blue Staining Kit (Invitrogen). The protocol used for in-gel trypsin digestion of proteins in gels was adapted from the method described in Shevchenko et al. (1996). Briefly, protein bands were manually excised and each band was cut into small pieces (~0.5 mm). The gel pieces were washed three times with a solution containing 50% methanol and 5% acetic acid for 2 h, twice with a solution containing 25 mM NH4HCO3 in 50% acetonitrile for 10 min each, and then the gel pieces were dried in a vacuum centrifuge. Reduction of proteins in gel pieces was performed with DTT and alkylation with iodoacetamide, and the gel pieces were washed and dried in a vacuum centrifuge. A trypsin solution in 25 mM NH4HCO3 containing 75 to 100 ng of sequencing grade modified trypsin (Promega) in 25-40 µl was added and incubated with gel pieces for 12-16 h at 37°C. To recover the tryptic peptides, a solution of 30 µl containing 5% formic acid and 50% acetonitril was added to the gel pieces, agitated in a vortex for 30-60 min and withdrawn into a new tube. The recovery was repeated once with 15 µl solution and the resulting two recovers were combined and dried in a vacuum centrifuge. The dried pellet was re-dissolved in 10-20 µl of 0.1% formic acid for LC-MS/MS analysis.
2013-05-28 | PXD000195 | Pride
Project description:Twenty microliter aliquots of BALF samples were dissolved in SDS-sample buffer and applied onto a 4-12% Nupage gel with MOPs running buffer. The run stopped after the samples migrated approximately ¼ distance into the gel. Each lane of the gel was sliced into smaller pieces, and subjected to destaining, reducing/alkylation, and in-gel trypsin digestion. The extracted peptides were applied for LC-MS/MS analysis using either a Thermo Orbitrap Fusion or a Thermo Orbitrap Fusion Lumos operated with an in-line Thermo nLC 1200 and an EASY-Spray ion source. Pepetides were separated using a 2 cm Pepmap 100 C18 trap column and a 25 cm Easy-spray Pepmap 100 C18 analytical column. MS/MS data acquisitions were operated at a 120,000 resolution (m/z 200) with a scan range of 350-1950 m/z and CID fragmentation.
2023-10-24 | PXD045119 | Pride
Project description:To identify Arabidopsis Wdr8 interactors, immunoprecipitation associated LC-MS/MS analysis was carried out. Crude proteins extracted from Wdr8-GFP expressing transgenic plants was subjected to the immuno-precipitation assay using GFP antibody magnetic beads (µMACS GFP isolation kit, Miltenyi Biotec). Co-purified proteins were separated by 10% SDS-PAGE gel and stained with SYPRO Ruby (BioRad laboratories). The stained protein bands were excised into several fraction pieces according to protein sizes, and in-gel protein digestion by trypsin was carried out. Purified protein peptides were subjected to LC-MS/MS analysis (LTQ-Orbitrap XL-HTC-PAL system). Collected MS/MS peak spectra was analyzed by the MASCOT server to identify peptide sequence.
2022-02-17 | PXD026063 | Pride
Project description:Crosslinking and immunoprecipitation (CLIP) is increasingly used to map transcriptome-wide binding sites of RNA-binding proteins (RBPs). We developed a method for CLIP data analysis and applied it to compare 254 nm CLIP with PAR-CLIP, which involves crosslinking of photoreactive nucleotides with 365 nm UV light. We found small differences in the accuracy of these methods in identifying binding sites of HuR, a protein that binds low-complexity sequences and Argonaute 2, which has a complex binding specificity. We show that crosslink-induced mutations lead to single-nucleotide resolution for both PAR-CLIP and CLIP. Our results confirm the expectation from original CLIP publications that RNA-binding proteins do not protect sufficiently their sites under the denaturing conditions used during the CLIP procedure, and we show that extensive digestion with sequence-specific ribonucleases strongly biases the set of recovered binding sites. We finally show that this bias can be substantially reduced by milder nuclease digestion conditions. We performed duplicate experiments for each variant of the CLIP protocol (CLIP, PAR-CLIP), each protein (HuR, Ago2), and enzymatic digestion (complete T1 digestion, mild MNase digestion). In addition, we performed a single PAR-CLIP experiment with mild T1 digestion.
2011-05-15 | E-GEOD-28859 | biostudies-arrayexpress
Project description:The lysosome is the main degradative organelle in eukaryotic cells. It is involved in diverse cellular functions from intracellular digestion to metabolic signaling. Despite various efforts to enrich for lysosomes and analyze their proteome with mass spectrometry based proteomics approaches, no systematic evaluation of sample preparation parameters for the analysis of lysosome enriched fractions has been performed. Using samples enriched for lysosomes with paramagnetic nanoparticles, we conducted a systematic evaluation of the protocol for the analysis of the lysosomal proteome. We compared centrifugation and protein precipitation for the concentration of lysosome enriched fractions and tested four different digestion methods in combination with each of these approaches. This included filter aided sample preparation (FASP), in-gel digestion, and in solution digestion using either RapiGest or Urea. Furthermore, we evaluated three formats for sample desalting, four gradient lengths for LC-MSMS analysis of unfractionated samples, as well as fractionation by strong anion exchange tip columns into three or six fractions. Using the combined data, we generated a draft map of lysosomal proteome for mouse embryonic fibroblasts as well as a spectral library for the analysis of lysosomes by data independent acquisition (DIA) and evaluated different LC gradient lengths for DIA.
2020-02-17 | PXD014576 | Pride