Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Comparative proteomics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources

Proteomic analysis of mouse liver for the evaluation of effects of Scutellariae radix by liquid chromatography with tandem mass spectrometry.

Scutellariae radix or Scutellaria baicalensis is a medicinal plant that contains major flavonoids such as baicalein, baicalin, wogonin and wogonosides. The present work describes the development of an approach using proteomic analysis of mouse liver to study the effects of prolonged exposure to substances present in chemically standardized Scutellariae radix extracts. Histopathological examination of the mouse liver was compared with the proteome data. The botanical extracts were prepared using pressurized liquid extraction (PLE). A method without isotope labeling was developed, using proteolytic digestion with one- and two-dimensional liquid chromatography with tandem mass spectrometry, and was used to characterize the extent of differential protein expression in mouse liver in response to external factors such as extracts from Scutellariae radix. From the histopathological examination and proteome data, significant changes in the mouse livers were not observed for the low-dose group. The Scutellariae radix extracts at high dose were observed to cause damage at the bile duct and expression change of a number of proteins including some involved in catabolism of triglyceride-rich particles, carbohydrate metabolism, regulators of cell signaling processes, and enzymes involved in biotransformation. Thus, proteomic analysis of liver samples from mice treated with botanical extracts is a promising approach to provide information on any potential toxicity effects of the extracts. The present method also provides another means for comparing proteomes in biological samples such as liver lysates from mice subjected to different treatments.

Animals↗

Proteomic dissection of plant development.

Plant development is controlled by complex endogenous genetic programs and responses to environmental cues. Proteome analyses have recently been introduced to plant biology to identify proteins instrumental in these developmental processes. To date most plant proteome studies have been employed to generate reference maps of the most abundant soluble proteins of plant organs at a defined developmental stage. However, proteomics is now also utilized for genetic studies comparing the proteomes of different plant genotypes, for physiological studies analyzing the influences of exogenous signals on a particular plant organ, and developmental studies investigating proteome changes during development. Technical advances are now beginning to allow a proteomic dissection of individual cell types, thus greatly increasing the information revealed by proteome analyses.

Plant Development↗

A proteomic approach for dissecting H-Ras signaling networks in NIH/3T3 mouse embryonic fibroblast cells.

To elucidate an understanding into H-Ras protein network, we have established various oncogene H-Ras-expressing NIH/3T3 mouse embryonic fibroblast cell clones, which are expressing G12V H-Ras, G12R H-Ras, and G12V/T35S H-Ras proteins under the tight control of expression by an antibiotic doxycycline. Here we provide a catalog of proteome profiles in total cell lysate derived from the oncogenic and partial loss of function H-Ras-expressing NIH/3T3 cells. In this biological context, we compared total proteome changes by the combined methods of 2-DE, quantitative image analysis and MALDI-TOF-MS analysis both commonly in oncogenic and partial loss of function H-Ras expression system. Thus, we tried to dissect H-Ras signaling pathway, especially a downstream effector molecule, Raf in NIH/3T3 cells using proteomics tools. In this study, we centralized upon the proteome profile changes as common targets for oncogenic H-Ras and a partial loss of function H-Ras in the H-Ras-expressing cells. Thirteen protein spots were selected as what the staining intensities on the gels for 2-DE images from both kinds of cells were consistently changed in their protein expression level. Differentially regulated expression was further confirmed for some subsets of candidates by semiquantitative RT-PCR and Western blot analysis using specific antibodies. Taken together, our results obtained and present here show that the comparative analysis of proteome from oncogenic and partial loss of function H-Ras-expressing cells has yielded interpretable data to elucidate the protein network directly and/or indirectly.

Animals↗

Spatial proteomic mapping of the human and mouse retina using IBEX.

We generated a comparative spatial proteomic atlas of the human and mouse retina using a highly multiplexed immunohistochemistry technique called iterative bleaching extends multiplexity (IBEX). We refined the IBEX workflow by integrating an antibody dissociation option alongside chemical bleaching. This dual strategy enabled removal of the entire antibody complex, permitting the flexible use of antibodies from the same host species across iterative cycles. We coupled this workflow with super-resolution imaging via deconvolution and applied it to the retina of healthy humans and WT mice and the Crb1rd8 mouse model. We successfully imaged over 25 protein markers on human and mouse tissue sections, generating spatial atlases of the major retinal cell populations. Cross-species protein expression was compared to scRNA-seq datasets to identify protein and transcript disparities. Super-resolution IBEX delineated the ultrastructural features of the outer limiting membrane (OLM), identifying CD44 as a core structural component tightly colocalized with a highly organized F-actin belt within Müller glial endfeet. Using the Crb1rd8 mouse model, disruption of this complex was spatially associated with rosette formation and OLM structural failure. In summary, spatial proteomic atlases of the human and mouse retina were used to reveal insights into the arrangement of major retinal cell populations and OLM structure.

Animals↗

A proteomic approach for unraveling the oncogenic H-Ras protein networks in NIH/3T3 mouse embryonic fibroblast cells.

To elucidate the oncogenic H-Ras network, we have established various stable and inducible oncogenic H-Ras-expressing NIH/3T3 mouse embryonic fibroblast cell clones, which express G12V H-Ras and G12R H-Ras proteins under the influence of a strong cytomegalovirus promoter and under the tight control of expression by an antibiotic, doxycycline, respectively. Here we provide a catalogue of proteome profiles in total cell lysates derived from oncogenic H-Ras-expressing NIH/3T3 cells. In this biological context, we compared total proteome changes by the combined methods of 2-DE, quantitative image analysis and MALDI-TOF MS analysis using both a stable expression system as well as an inducible expression system. There were a large number of common targets for oncogenic H-Ras, which were identified in both cell lines and consisted of 64 proteins (36 up-regulated and 28 down-regulated). Differentially regulated expression was further confirmed for some subsets of candidates by Western blot analysis using specific antibodies. Taken together, the results presented here show that comparative analysis of the proteome from the oncogenic H-Ras-expressing cells yielded interpretable data to elucidate protein networks directly and/or indirectly.

Animals↗

Changes in liver protein abundance in inbred alcohol-preferring rats due to chronic alcohol exposure, as measured through a proteomics approach.

This study compares the total liver proteome of inbred alcohol-preferring line (iP) rats exposed to alcohol with iP rats without alcohol experience. Rat liver proteins were extracted using a three-step procedure. Each of the three solutions solubilizes a different set of proteins. The extracted proteins were separated by 2-DE. Scanned gels of two sample groups, alcohol-exposed iP and alcohol-naïve iP, were compared, revealing many protein spots with significantly higher or lower densities. These spots were cut from the gel, destained, and subjected to trypsin digestion and subsequent identification by LC-MS/MS. Twenty-four individual rats, 12 alcohol-naïve, and 12 alcohol-exposed, were used in this study. Two groups, each containing six naïve and six exposed animals, were created for statistical comparison. For the first group, 64 spots were observed to have statistically significant intensity differences upon alcohol exposure across all three extracts while 118 such spots were found in the second group. There were 113 unique proteins in both groups together. The majority of these proteins were enzymes. Significant changes are observed for three major metabolic pathways: glycolysis, gluconeogenesis, and fatty acid beta-oxidation. In addition, enzymes involved in protein synthesis and antioxidant activity show significant changes in abundance in response to alcohol exposure.

Alcoholism↗

Comparative evaluation of mass spectrometry platforms used in large-scale proteomics investigations.

Researchers have several options when designing proteomics experiments. Primary among these are choices of experimental method, instrumentation and spectral interpretation software. To evaluate these choices on a proteome scale, we compared triplicate measurements of the yeast proteome by liquid chromatography tandem mass spectrometry (LC-MS/MS) using linear ion trap (LTQ) and hybrid quadrupole time-of-flight (QqTOF; QSTAR) mass spectrometers. Acquired MS/MS spectra were interpreted with Mascot and SEQUEST algorithms with and without the requirement that all returned peptides be tryptic. Using a composite target decoy database strategy, we selected scoring criteria yielding 1% estimated false positive identifications at maximum sensitivity for all data sets, allowing reasonable comparisons between them. These comparisons indicate that Mascot and SEQUEST yield similar results for LTQ-acquired spectra but less so for QSTAR spectra. Furthermore, low reproducibility between replicate data acquisitions made on one or both instrument platforms can be exploited to increase sensitivity and confidence in large-scale protein identifications.

Algorithms↗

Identification of tumor antigens in renal cell carcinoma by serological proteome analysis.

We have investigated the suitability of proteomics for identification of tumor-associated antigens. First, we compared the proteomes of nontumorous kidney and renal cell carcinoma (RCC) by two-dimensional gel electrophoresis (2-DE) and silver staining. Protein patterns were markedly different (approximately 800 spots in RCCs versus approximately 1400 spots in kidney). 2-DE immunoblotting revealed five RCC-specific spots, reproducibly reactive with RCC-patient but not healthy donor control sera. Two of these antigens were isolated by preparative 2-DE, and identified by Edman sequencing of tryptic peptides. The first antigen, smooth muscle protein 22-alpha (SM22-alpha), is an actin-binding protein of unknown function predominantly expressed in smooth muscle cells. In situ hybridization revealed that SM22-alpha is not expressed in the malignant cells but in mesenchymal cells of the tumor stroma. The second antigen represents carbonic anhydrase I (CAI), an isoform usually not expressed in kidney. Interestingly, a different isoform (CAXII) has previously been identified by serological expression cloning as an antigen overexpressed in some RCCs. In additional assays, antibodies to recombinant CAI or SM22-alpha were detected in sera from 3/11 or 5/11 RCC patients, respectively, whereas sera from 13 healthy individuals did not react. In conclusion, serological proteome analysis may be a new tool for the identification of tumor-associated antigens.

Amino Acid Sequence↗

Identification of differentially expressed proteins of gamma-ray irradiated rat intestinal epithelial IEC-6 cells by two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionisation-time of flight mass spectrometry.

To identify proteins involved in the processes of cellular and molecular response to radiation damage repair in intestinal epithelial IEC-6 cells, we comparatively analyzed the proteome of irradiated IEC-6 cells with that of normal cells. A series of methods were used, including two-dimensional gel electrophoresis (Z-DE), PDQuest software analysis of 2-DE gels, peptide mass fingerprinting based on matrix-assisted laser desorption/ionisation-time of flight-mass spectrometry (MALDI-TOF-MS), and Swiss-Prot database searching, to separate and identify differentially expressed proteins. Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR) were used to validate the differentially expressed proteins. Image analysis revealed that averages of 608 +/- 39 and 595 +/- 31 protein spots were detected in normal and irradiated IEC-6 cells, respectively. Sixteen differential protein spots were isolated from gels, and measured with MALDI-TOF-MS. A total of 14 spots yielded good spectra, and 11 spots matched with known proteins after database searching. These proteins were mainly involved in anti-oxidation, metabolism, and protein post-translational processes. Western blotting confirmed that stress-70 protein was down-regulated by gamma-irradiation. Up-regulation of ERP29 was confirmed by RT-PCR, indicating that it is involved in ionizing radiation. The clues provided by the comparative proteome strategy utilized here will shed light on molecular mechanisms of radiation damage repair in intestinal epithelial cells.

Animals↗

Comparative analysis of protein domain organization.

We have developed a set of graph theory-based tools, which we call Comparative Analysis of Protein Domain Organization (CADO), to survey and compare protein domain organizations of different organisms. In the language of CADO, the organization of protein domains in a given organism is shown as a domain graph in which protein domains are represented as vertices, and domain combinations, defined as instances of two domains found in one protein, are represented as edges. CADO provides a new way to analyze and compare whole proteomes, including identifying the consensus and difference of domain organization between organisms. CADO was used to analyze and compare >50 bacterial, archaeal, and eukaryotic genomes. Examples and overviews presented here include the analysis of the modularity of domain graphs and the functional study of domains based on the graph topology. We also report on the results of comparing domain graphs of two organisms, Pyrococcus horikoshii (an extremophile) and Haemophilus influenzae (a parasite with reduced genome) with other organisms. Our comparison provides new insights into the genome organization of these organisms. Finally, we report on the specific domain combinations characterizing the three kingdoms of life, and the kingdom "signature" domain organizations derived from those specific domain combinations.

Animals↗

Application of two-dimensional gel electrophoresis to interrogate alterations in the proteome of gentically modified crops. 3. Assessing unintended effects.

The current procedures to assess the safety of food and feed derived from modern biotechnology include the investigation of possible unintended effects. To improve the probability of detecting unintended effects, profiling techniques such as proteomics are currently tested as complementary analytical tools to the existing safety assessment. An optimized two-dimensional gel electrophoresis (2DE) method was used as a proteomics approach to investigate insertional and pleiotropic effects on the proteome due to genetic engineering. Twelve transgenic Arabidopsis thaliana lines were analyzed by 2DE, and their seed proteomes were compared to that of their parental line as well as to 12 Arabidopsis ecotype lines. The genetic modification of the Arabidopsis lines, using three different genes and three different promoters, did not cause unintended changes to the analyzed seed proteome. Differences in spot quantity between transgenic and nontransgenic lines fell in the range of values found in the 12 Arabidopsis ecotype lines or were related to the introduced gene.

Arabidopsis↗

The use of proteomics for the assessment of clinical samples in research.

Proteomics, the analysis of expressed proteins, has been an important developing area of research for the past two decades [Anderson, NG, Anderson, NL. Twenty years of two-dimensional electrophoresis: past, present and future. Electrophoresis 1996;17:443-453]. Advances in technology have led to a rapid increase in applications to a wide range of samples; from initial experiments using cell lines, more complex tissues and biological fluids are now being assessed to establish changes in protein expression. A primary aim of clinical proteomics is the identification of biomarkers for diagnosis and therapeutic intervention of disease, by comparing the proteomic profiles of control and disease, and differing physiological states. This expansion into clinical samples has not been without difficulties owing to the complexity and dynamic range in plasma and human tissues including tissue biopsies. The most widely used techniques for analysis of clinical samples are surface-enhanced laser desorption/ionisation mass spectrometry (SELDI-MS) and 2-dimensional gel electrophoresis (2-DE) coupled to matrix-assisted laser desorption ionisation [Person, MD, Monks, TJ, Lau, SS. An integrated approach to identifying chemically induced posttranslational modifications using comparative MALDI-MS and targeted HPLC-ESI-MS/MS. Chem. Res. Toxicol. 2003;16:598-608]-mass spectroscopy (MALDI-MS). This review aims to summarise the findings of studies that have used proteomic research methods to analyse samples from clinical studies and to assess the impact that proteomic techniques have had in assessing clinical samples.

Biomarkers↗

COPASAAR--a database for proteomic analysis of single amino acid repeats.

BACKGROUND: Single amino acid repeats make up a significant proportion in all of the proteomes that have currently been determined. They have been shown to be functionally and medically significant, and are associated with cancers and neuro-degenerative diseases such as Huntington's Chorea, where a poly-glutamine repeat is responsible for causing the disease. The COPASAAR database is a new tool to facilitate the rapid analysis of single amino acid repeats at a proteome level. The database aims to simplify the comparison of repeat distributions between proteomes in order to provide a better understanding of their function and evolution. RESULTS: A comparative analysis of all proteomes in the database (currently 244) shows that single amino acid repeats account for about 12-14% of the proteome of any given species. They are more common in eukaryotes (14%) than in either archaea or bacteria (both 13%). Individual analyses of proteomes show that long single amino acid repeats (6+ residues) are much more common in the Eukaryotes and that longer repeats are usually made up of hydrophilic amino acids such as glutamine, glutamic acid, asparagine, aspartic acid and serine. CONCLUSION: COPASAAR is a useful tool for comparative proteomics that provides rapid access to amino acid repeat data that can be readily data-mined. The COPASAAR database can be queried at the kingdom, proteome or individual protein level. As the amount of available proteome data increases this will be increasingly important in order to automate proteome comparison. The insights gained from these studies will give a better insight into the evolution of protein sequence and function.

Algorithms↗

Proteomic analysis of anaplastic lymphoma cell lines: identification of potential tumour markers.

Anaplastic large-cell lymphomas (ALCL) are high grade lymphomas of T or null phenotype often associated with the t(2;5) translocation leading to the expression of a chimeric protein consisting of the N-terminal portion of nucleophosmin (NPM) and the intracellular domain of the anaplastic lymphoma kinase (ALK). Although ALCL are recognized as distinct clinical, biological and cytogenetic entities, heterogeneities persist in this group of tumours, which exhibit a broad spectrum of morphological features. Particularly, the common type tumour consisting in large cells contrast with the small cell variant that is sometimes associated with a leukemic phase. The ALK-negative ALCL is often associated with a poor prognosis. Here, we investigated the proteome of these subtypes of tumours using patient-derived cell lines. We compared the proteome of the cytosolic fraction of NPM-ALK-positive versus NPM-ALK-negative cells on one hand, and the proteome of common cell type versus small cell variant on the other hand. The identification of a set of proteins differentially expressed in the subtypes of ALCL points to new diagnosis/prognosis markers. This study also provides interesting information on the molecular mechanisms responsible for the different subtypes of ALCL.

Anaplastic Lymphoma Kinase↗

Comparison of two proteomics techniques used to identify proteins regulated by gibberellin in rice.

Proteomics has become an essential methodology for large-scale analysis of proteins in various fields of plant biology. We compared two proteomics techniques, two-dimensional liquid chromatography (2D-LC) and fluorescence two-dimensional difference gel electrophoresis (2D-DIGE), for their ability to identify proteins regulated by gibberellin (GA) in rice. Two-week-old rice seedlings were treated with or without 5 microM GA3 for 48 h and proteins extracted from the basal region of the leaf sheath. After separation of the proteins by the two techniques, the amino acid sequences of GA3-responsive proteins were analyzed using a protein sequencer and mass spectrometry. 2D-LC and 2D-DIGE were able to resolve 1248 protein fractions and 1500 proteins, respectively. Out of these, 2D-LC identified 9 proteins that were up-regulated and 9 that were down-regulated by GA treatment; 2D-DIGE identified 4 up-regulated and 4 down-regulated proteins. The two techniques detected overlapping sets of proteins. For example, cytosolic glyceraldehyde-3-phosphate dehydrogenase and photosystem II oxygen-evolving complex protein were identified as GA3-regulated proteins by both methods. In addition, these two methods uncovered GA3-regulated unknown proteins which had not been reported previously, and novel proteins which are not detected in 2D-PAGE followed by Coomassie brilliant blue staining. These results suggest that these two methods are among some of the very useful tools for detecting proteins that may function in various physiological and developmental processes in plants.

Chromatography, Liquid↗

Analyzing proteomes and protein function using graphical comparative analysis of tandem mass spectrometry results.

Although generating large amounts of proteomic data using tandem mass spectrometry has become routine, there is currently no single set of comprehensive tools for the rigorous analysis of tandem mass spectrometry results given the large variety of possible experimental aims. Currently available applications are typically designed for displaying proteins and posttranslational modifications from the point of view of the mass spectrometrist and are not versatile enough to allow investigators to develop biological models of protein function, protein structure, or cell state. In addition, storage and dissemination of mass spectrometry-based proteomic data are problems facing the scientific community. To address these issues, we have developed a relational database model that efficiently stores and manages large amounts of tandem mass spectrometry results. We have developed an integrated suite of multifunctional analysis software for interpreting, comparing, and displaying these results. Our system, Bioinformatic Graphical Comparative Analysis Tools (BIGCAT), allows sophisticated analysis of tandem mass spectrometry results in a biologically intuitive format and provides a solution to many data storage and dissemination issues.

Amino Acid Sequence↗

Expanding the subproteome of the inner mitochondria using protein separation technologies: one- and two-dimensional liquid chromatography and two-dimensional gel electrophoresis.

Currently no single proteomics technology has sufficient analytical power to allow for the detection of an entire proteome of an organelle, cell, or tissue. One approach that can be used to expand proteome coverage is the use of multiple separation technologies especially if there is minimal overlap in the proteins observed by the different methods. Using the inner mitochondrial membrane subproteome as a model proteome, we compared for the first time the ability of three protein separation methods (two-dimensional liquid chromatography using the ProteomeLab PF 2D Protein Fractionation System from Beckman Coulter, one-dimensional reversed phase high performance liquid chromatography, and two-dimensional gel electrophoresis) to determine the relative overlap in protein separation for these technologies. Data from these different methods indicated that a strikingly low number of proteins overlapped with less than 24% of proteins common between any two technologies and only 7% common among all three methods. Utilizing the three technologies allowed the creation of a composite database totaling 348 non-redundant proteins. 82% of these proteins had not been observed previously in proteomics studies of this subproteome, whereas 44% had not been identified in proteomics studies of intact mitochondria. Each protein separation method was found to successfully resolve a unique subset of proteins with the liquid chromatography methods being more suited for the analysis of transmembrane domain proteins and novel protein discovery. We also demonstrated that both the one- and two-dimensional LC allowed for the separation of the alpha-subunit of F1F0 ATP synthase that differed due to a change in pI or hydrophobicity.

Animals↗

[Comparison of the proteome of the sporutated oocysts of Eimeria tenella diclazuril sensitive strain with diclazuril resistant strain].

Two-dimensional electrophoresis (2-DE) was employed to compare the proteome of Diclazuril-resistance Eimeria tenella with that of sensitive strains for identifying unique proteins of these stains. 5 protein spots were found to express differentially. Four spots which remarkably were measured by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). The data obtained from peptide mass fingerprinting were used in NCBInr database search, two protein spots in gel were identified as Eimeria tenella sporulated oocyst TA4 antigen protein, Heat shock 70kD protein, two protein spots were functional proteins of Eukaryote. These proteins are potentially basic work for finding molecular mechanism about drug-resistance of Eimeria tenella and new marker in the detection of resistance of Eimeria tenella.

Animals↗