1
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Popova L, Carr RA, Carabetta VJ. Recent Contributions of Proteomics to Our Understanding of Reversible N ε-Lysine Acylation in Bacteria. J Proteome Res 2024; 23:2733-2749. [PMID: 38442041 PMCID: PMC11296938 DOI: 10.1021/acs.jproteome.3c00912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Post-translational modifications (PTMs) have been extensively studied in both eukaryotes and prokaryotes. Lysine acetylation, originally thought to be a rare occurrence in bacteria, is now recognized as a prevalent and important PTM in more than 50 species. This expansion in interest in bacterial PTMs became possible with the advancement of mass spectrometry technology and improved reagents such as acyl-modification specific antibodies. In this Review, we discuss how mass spectrometry-based proteomic studies of lysine acetylation and other acyl modifications have contributed to our understanding of bacterial physiology, focusing on recently published studies from 2018 to 2023. We begin with a discussion of approaches used to study bacterial PTMs. Next, we discuss newly characterized acylomes, including acetylomes, succinylomes, and malonylomes, in different bacterial species. In addition, we examine proteomic contributions to our understanding of bacterial virulence and biofilm formation. Finally, we discuss the contributions of mass spectrometry to our understanding of the mechanisms of acetylation, both enzymatic and nonenzymatic. We end with a discussion of the current state of the field and possible future research avenues to explore.
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Affiliation(s)
- Liya Popova
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, New Jersey 08103, United States
| | - Rachel A Carr
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, New Jersey 08103, United States
| | - Valerie J Carabetta
- Department of Biomedical Sciences, Cooper Medical School of Rowan University, Camden, New Jersey 08103, United States
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2
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Dowling P, Swandulla D, Ohlendieck K. Mass Spectrometry-Based Proteomic Technology and Its Application to Study Skeletal Muscle Cell Biology. Cells 2023; 12:2560. [PMID: 37947638 PMCID: PMC10649384 DOI: 10.3390/cells12212560] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 10/27/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
Voluntary striated muscles are characterized by a highly complex and dynamic proteome that efficiently adapts to changed physiological demands or alters considerably during pathophysiological dysfunction. The skeletal muscle proteome has been extensively studied in relation to myogenesis, fiber type specification, muscle transitions, the effects of physical exercise, disuse atrophy, neuromuscular disorders, muscle co-morbidities and sarcopenia of old age. Since muscle tissue accounts for approximately 40% of body mass in humans, alterations in the skeletal muscle proteome have considerable influence on whole-body physiology. This review outlines the main bioanalytical avenues taken in the proteomic characterization of skeletal muscle tissues, including top-down proteomics focusing on the characterization of intact proteoforms and their post-translational modifications, bottom-up proteomics, which is a peptide-centric method concerned with the large-scale detection of proteins in complex mixtures, and subproteomics that examines the protein composition of distinct subcellular fractions. Mass spectrometric studies over the last two decades have decisively improved our general cell biological understanding of protein diversity and the heterogeneous composition of individual myofibers in skeletal muscles. This detailed proteomic knowledge can now be integrated with findings from other omics-type methodologies to establish a systems biological view of skeletal muscle function.
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Affiliation(s)
- Paul Dowling
- Department of Biology, Maynooth University, National University of Ireland, W23 F2H6 Maynooth, Co. Kildare, Ireland;
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, W23 F2H6 Maynooth, Co. Kildare, Ireland
| | - Dieter Swandulla
- Institute of Physiology, Faculty of Medicine, University of Bonn, D53115 Bonn, Germany;
| | - Kay Ohlendieck
- Department of Biology, Maynooth University, National University of Ireland, W23 F2H6 Maynooth, Co. Kildare, Ireland;
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, W23 F2H6 Maynooth, Co. Kildare, Ireland
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3
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Schaffer LV, Shortreed MR, Smith LM. Proteoform Analysis and Construction of Proteoform Families in Proteoform Suite. Methods Mol Biol 2022; 2500:67-81. [PMID: 35657588 PMCID: PMC9694099 DOI: 10.1007/978-1-0716-2325-1_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Proteoform Suite is an interactive software program for the identification and quantification of intact proteoforms from mass spectrometry data. Proteoform Suite identifies proteoforms observed by intact-mass (MS1) analysis. In intact-mass analysis, unfragmented experimental proteoforms are compared to a database of known proteoform sequences and to one another, searching for mass differences corresponding to well-known post-translational modifications or amino acids. Intact-mass analysis enables proteoforms observed in the MS1 data without MS/MS (MS2) fragmentation to be identified. Proteoform Suite further facilitates the construction and visualization of proteoform families, which are the sets of proteoforms derived from individual genes. Bottom-up peptide identifications and top-down (MS2) proteoform identifications can be integrated into the Proteoform Suite analysis to increase the sensitivity and accuracy of the analysis. Proteoform Suite is open source and freely available at https://github.com/smith-chem-wisc/proteoform-suite .
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Affiliation(s)
- Leah V Schaffer
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | | | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
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4
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Sun RX, Wang RM, Luo L, Liu C, Chi H, Zeng WF, He SM. Accurate Proteoform Identification and Quantitation Using pTop 2.0. Methods Mol Biol 2022; 2500:105-129. [PMID: 35657590 DOI: 10.1007/978-1-0716-2325-1_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The remarkable advancement of top-down proteomics in the past decade is driven by the technological development in separation, mass spectrometry (MS) instrumentation, novel fragmentation, and bioinformatics. However, the accurate identification and quantification of proteoforms, all clearly-defined molecular forms of protein products from a single gene, remain a challenging computational task. This is in part due to the complicated mass spectra from intact proteoforms when compared to those from the digested peptides. Herein, pTop 2.0 is developed to fill in the gap between the large-scale complex top-down MS data and the shortage of high-accuracy bioinformatic tools. Compared with pTop 1.0, the first version, pTop 2.0 concentrates mainly on the identification of the proteoforms with unexpected modifications or a terminal truncation. The quantitation based on isotopic labeling is also a new function, which can be carried out by the convenient and user-friendly "one-key operation," integrated together with the qualitative identifications. The accuracy and running speed of pTop 2.0 is significantly improved on the test data sets. This chapter will introduce the main features, step-by-step running operations, and algorithmic developments of pTop 2.0 in order to push the identification and quantitation of intact proteoforms to a higher-accuracy level in top-down proteomics.
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Affiliation(s)
- Rui-Xiang Sun
- National Institute of Biological Sciences, Beijing, China.
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China.
| | - Rui-Min Wang
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Lan Luo
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Chao Liu
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Hao Chi
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Wen-Feng Zeng
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
| | - Si-Min He
- Institute of Computing Technology, Chinese Academy of Sciences, Beijing, China
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5
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Tiambeng TN, Wu Z, Melby JA, Ge Y. Size Exclusion Chromatography Strategies and MASH Explorer for Large Proteoform Characterization. Methods Mol Biol 2022; 2500:15-30. [PMID: 35657584 PMCID: PMC9703982 DOI: 10.1007/978-1-0716-2325-1_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Top-down mass spectrometry (MS)-based analysis of larger proteoforms (>50 kDa) is typically challenging due to an exponential decay in the signal-to-noise ratio with increasing protein molecular weight (MW) and coelution with low-MW proteoforms. Size exclusion chromatography (SEC) fractionates proteins based on their size, separating larger proteoforms from those of smaller size in the proteome. In this protocol, we initially describe the use of SEC to fractionate high-MW proteoforms from low-MW proteoforms. Subsequently, the SEC fractions containing the proteoforms of interest are subjected to reverse-phase liquid chromatography (RPLC) coupled online with high-resolution MS. Finally, proteoforms are characterized using MASH Explorer, a user-friendly software environment for in-depth proteoform characterization.
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Affiliation(s)
- Timothy N. Tiambeng
- Department of Chemistry, University of Wisconsin – Madison, Madison, WI 53706
| | - Zhijie Wu
- Department of Chemistry, University of Wisconsin – Madison, Madison, WI 53706
| | - Jake A. Melby
- Department of Chemistry, University of Wisconsin – Madison, Madison, WI 53706
| | - Ying Ge
- Department of Chemistry, University of Wisconsin – Madison, Madison, WI 53706,Department of Cell and Regenerative Biology, University of Wisconsin – Madison, Madison, WI 53705,Human Proteomic Program, University of Wisconsin – Madison, Madison WI 53705,To whom correspondence may be addressed: Dr. Ying Ge, 8551 WIMR-II, 1111 Highland Ave., Madison, Wisconsin 53705, USA. ; Tel: 608-265-4744
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6
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Kaulich PT, Winkels K, Kaulich TB, Treitz C, Cassidy L, Tholey A. MSTopDiff: A Tool for the Visualization of Mass Shifts in Deconvoluted Top-Down Proteomics Data for the Database-Independent Detection of Protein Modifications. J Proteome Res 2021; 21:20-29. [PMID: 34818005 DOI: 10.1021/acs.jproteome.1c00766] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Top-down proteomics analyzes intact proteoforms with all of their post-translational modifications and genetic and RNA splice variants. In addition, modifications introduced either deliberately or inadvertently during sample preparation, that is, via oxidation, alkylation, or labeling reagents, or through the formation of noncovalent adducts (e.g., detergents) further increase the sample complexity. To facilitate the recognition of protein modifications introduced during top-down analysis, we developed MSTopDiff, a software tool with a graphical user interface written in Python, which allows one to detect protein modifications by calculating and visualizing mass differences in top-down data without the prerequisite of a database search. We demonstrate the successful application of MSTopDiff for the detection of artifacts originating from oxidation, formylation, overlabeling during isobaric labeling, and adduct formation with cations or sodium dodecyl sulfate. MSTopDiff offers several modes of data representation using deconvoluted MS1 or MS2 spectra. In addition to artificial modifications, the tool enables the visualization of biological modifications such as phosphorylation and acetylation. MSTopDiff provides an overview of the artificial and biological modifications in top-down proteomics samples, which makes it a valuable tool in quality control of standard workflows and for parameter evaluation during method development.
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Affiliation(s)
- Philipp T Kaulich
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Konrad Winkels
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Tobias B Kaulich
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Christian Treitz
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Liam Cassidy
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
| | - Andreas Tholey
- Systematic Proteome Research & Bioanalytics, Institute for Experimental Medicine, Christian-Albrechts-Universität zu Kiel, 24105 Kiel, Germany
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7
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Abstract
Proteoform identification is required to fully understand the biological diversity present in a sample. However, these identifications are often ambiguous because of the challenges in analyzing full length proteins by mass spectrometry. A five-level proteoform classification system was recently developed to delineate the ambiguity of proteoform identifications and to allow for comparisons across software platforms and acquisition methods. Widespread adoption of this system requires software tools to provide classification of the proteoform identifications. We describe here an implementation of the five-level classification system in the software program MetaMorpheus, which provides both bottom-up and top-down identifications. Additionally, we developed a stand-alone program called ProteoformClassifier that allows users to classify proteoform results from any search program, provided that the program writes output that includes the information necessary to evaluate proteoform ambiguity. This stand-alone program includes a small test file and database to evaluate if a given program provides sufficient information to evaluate ambiguity. If the program does not, then ProteoformClassifier provides meaningful feedback to assist developers with implementing the classification system. We tested currently available top-down software programs and found that none of them (other than MetaMorpheus) provided sufficient information regarding identification ambiguity to permit classification.
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Affiliation(s)
- Zach Rolfs
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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8
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Lu L, Scalf M, Shortreed MR, Smith LM. Mesh Fragmentation Improves Dissociation Efficiency in Top-down Proteomics. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1319-1325. [PMID: 33754701 PMCID: PMC8783543 DOI: 10.1021/jasms.0c00462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Top-down proteomics is a key mass spectrometry-based technology for comprehensive analysis of proteoforms. Proteoforms exhibit multiple high charge states and isotopic forms in full MS scans. The dissociation behavior of proteoforms in different charge states and subjected to different collision energies is highly variable. The current widely employed data-dependent acquisition (DDA) method selects a narrow m/z range (corresponding to a single proteoform charge state) for dissociation from the most abundant precursors. We describe here Mesh, a novel dissociation strategy, to dissociate multiple charge states of one proteoform with multiple collision energies. We show that the Mesh strategy has the potential to generate fragment ions with improved sequence coverage and improve identification ratios in top-down proteomic analyses of complex samples. The strategy is implemented within an open-source instrument control software program named MetaDrive to perform real time deconvolution and precursor selection.
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Affiliation(s)
- Lei Lu
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Mark Scalf
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Michael R. Shortreed
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Lloyd M. Smith
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
- Corresponding Author Phone: (608) 263-2594. Fax: (608) 265-6780.
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9
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Combinations of histone post-translational modifications. Biochem J 2021; 478:511-532. [DOI: 10.1042/bcj20200170] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 01/13/2021] [Accepted: 01/18/2021] [Indexed: 12/20/2022]
Abstract
Histones are essential proteins that package the eukaryotic genome into its physiological state of nucleosomes, chromatin, and chromosomes. Post-translational modifications (PTMs) of histones are crucial to both the dynamic and persistent regulation of the genome. Histone PTMs store and convey complex signals about the state of the genome. This is often achieved by multiple variable PTM sites, occupied or unoccupied, on the same histone molecule or nucleosome functioning in concert. These mechanisms are supported by the structures of ‘readers’ that transduce the signal from the presence or absence of PTMs in specific cellular contexts. We provide background on PTMs and their complexes, review the known combinatorial function of PTMs, and assess the value and limitations of common approaches to measure combinatorial PTMs. This review serves as both a reference and a path forward to investigate combinatorial PTM functions, discover new synergies, and gather additional evidence supporting that combinations of histone PTMs are the central currency of chromatin-mediated regulation of the genome.
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10
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Schaffer LV, Anderson LC, Butcher DS, Shortreed MR, Miller RM, Pavelec C, Smith LM. Construction of Human Proteoform Families from 21 Tesla Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Top-Down Proteomic Data. J Proteome Res 2020; 20:317-325. [PMID: 33074679 DOI: 10.1021/acs.jproteome.0c00403] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Identification of proteoforms, the different forms of a protein, is important to understand biological processes. A proteoform family is the set of different proteoforms from the same gene. We previously developed the software program Proteoform Suite, which constructs proteoform families and identifies proteoforms by intact-mass analysis. Here, we have applied this approach to top-down proteomic data acquired at the National High Magnetic Field Laboratory 21 tesla Fourier transform ion cyclotron resonance mass spectrometer (data available on the MassIVE platform with identifier MSV000085978). We explored the ability to construct proteoform families and identify proteoforms from the high mass accuracy data that this instrument provides for a complex cell lysate sample from the MCF-7 human breast cancer cell line. There were 2830 observed experimental proteforms, of which 932 were identified, 44 were ambiguous, and 1854 were unidentified. Of the 932 unique identified proteoforms, 766 were identified by top-down MS2 analysis at 1% false discovery rate (FDR) using TDPortal, and 166 were additional intact-mass identifications (∼4.7% calculated global FDR) made using Proteoform Suite. We recently published a proteoform level schema to represent ambiguity in proteoform identifications. We implemented this proteoform level classification in Proteoform Suite for intact-mass identifications, which enables users to determine the ambiguity levels and sources of ambiguity for each intact-mass proteoform identification.
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Affiliation(s)
- Leah V Schaffer
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Lissa C Anderson
- Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - David S Butcher
- Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Michael R Shortreed
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Rachel M Miller
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Caitlin Pavelec
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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11
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Manzano-Román R, Fuentes M. Relevance and proteomics challenge of functional posttranslational modifications in Kinetoplastid parasites. J Proteomics 2020; 220:103762. [PMID: 32244008 DOI: 10.1016/j.jprot.2020.103762] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/06/2020] [Accepted: 03/23/2020] [Indexed: 02/06/2023]
Abstract
Protozoan parasitic infections are health, social and economic issues impacting both humans and animals, with significant morbidity and mortality worldwide. Protozoan parasites have complicated life cycles with both intracellular and extracellular forms. As a consequence, protozoan adapt to changing environments in part through a dynamic enzyme-catalyzed process leading to reversible posttranslational modifications (PTMs). The characterization by proteomics approaches reveals the critical role of the PTMs of the proteins involved in host-pathogen interaction. The complexity of PTMs characterization is increased by the high diversity, stoichiometry, dynamic and also co-existence of several PTMs in the same moieties which crosstalk between them. Here, we review how to understand the complexity and the essential role of PTMs crosstalk in order to provide a new hallmark for vaccines developments, immunotherapies and personalized medicine. In addition, the importance of these motifs in the biology and biological cycle of kinetoplastid parasites is highlighted with key examples showing the potential to act as targets against protozoan diseases.
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Affiliation(s)
- R Manzano-Román
- Proteomics Unit, Cancer Research Centre (IBMCC/CSIC/USAL/IBSAL), 37007, Salamanca, Spain..
| | - M Fuentes
- Proteomics Unit, Cancer Research Centre (IBMCC/CSIC/USAL/IBSAL), 37007, Salamanca, Spain.; Proteomics Unit, Cancer Research Centre (IBMCC/CSIC/USAL/IBSAL), 37007 Salamanca, Spain; Department of Medicine and General Cytometry Service-Nucleus, Cancer Research Centre (IBMCC/CSIC/USAL/IBSAL), 37007, Salamanca, Spain
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12
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Dai Y, Buxton KE, Schaffer LV, Miller RM, Millikin RJ, Scalf M, Frey BL, Shortreed MR, Smith LM. Constructing Human Proteoform Families Using Intact-Mass and Top-Down Proteomics with a Multi-Protease Global Post-Translational Modification Discovery Database. J Proteome Res 2019; 18:3671-3680. [PMID: 31479276 DOI: 10.1021/acs.jproteome.9b00339] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Complex human biomolecular processes are made possible by the diversity of human proteoforms. Constructing proteoform families, groups of proteoforms derived from the same gene, is one way to represent this diversity. Comprehensive, high-confidence identification of human proteoforms remains a central challenge in mass spectrometry-based proteomics. We have previously reported a strategy for proteoform identification using intact-mass measurements, and we have since improved that strategy by mass calibration based on search results, the use of a global post-translational modification discovery database, and the integration of top-down proteomics results with intact-mass analysis. In the present study, we combine these strategies for enhanced proteoform identification in total cell lysate from the Jurkat human T lymphocyte cell line. We collected, processed, and integrated three types of proteomics data (NeuCode-labeled intact-mass, label-free top-down, and multi-protease bottom-up) to maximize the number of confident proteoform identifications. The integrated analysis revealed 5950 unique experimentally observed proteoforms, which were assembled into 848 proteoform families. Twenty percent of the observed proteoforms were confidently identified at a 3.9% false discovery rate, representing 1207 unique proteoforms derived from 484 genes.
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Affiliation(s)
- Yunxiang Dai
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States.,Biophysics Graduate Program , University of Wisconsin , 413 Bock Laboratories, 1525 Linden Drive , Madison , Wisconsin 53706 , United States
| | - Katherine E Buxton
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Leah V Schaffer
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Rachel M Miller
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Robert J Millikin
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Mark Scalf
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Brian L Frey
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Michael R Shortreed
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
| | - Lloyd M Smith
- Department of Chemistry , University of Wisconsin , 1101 University Avenue , Madison , Wisconsin 53706 , United States
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13
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Schaffer LV, Tucholski T, Shortreed MR, Ge Y, Smith LM. Intact-Mass Analysis Facilitating the Identification of Large Human Heart Proteoforms. Anal Chem 2019; 91:10937-10942. [PMID: 31393705 DOI: 10.1021/acs.analchem.9b02343] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Proteoforms, the primary effectors of biological processes, are the different forms of proteins that arise from molecular processing events such as alternative splicing and post-translational modifications. Heart diseases exhibit changes in proteoform levels, motivating the development of a deeper understanding of the heart proteoform landscape. Our recently developed two-dimensional top-down proteomics platform coupling serial size exclusion chromatography (sSEC) to reversed-phase chromatography (RPC) expanded coverage of the human heart proteome and allowed observation of high-molecular weight proteoforms. However, most of these observed proteoforms were not identified due to the difficulty in obtaining quality tandem mass spectrometry (MS2) fragmentation data for large proteoforms from complex biological mixtures on a chromatographic time scale. Herein, we sought to identify human heart proteoforms in this data set using an enhanced version of Proteoform Suite, which identifies proteoforms by intact mass alone. Specifically, we added a new feature to Proteoform Suite to determine candidate identifications for isotopically unresolved proteoforms larger than 50 kDa, enabling subsequent MS2 identification of important high-molecular weight human heart proteoforms such as lamin A (72 kDa) and trifunctional enzyme subunit α (79 kDa). With this new workflow for large proteoform identification, endogenous human cardiac myosin binding protein C (140 kDa) was identified for the first time. This study demonstrates the integration of our sSEC-RPC-MS proteomics platform with intact-mass analysis through Proteoform Suite to create a catalog of human heart proteoforms and facilitate the identification of large proteoforms in complex systems.
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Affiliation(s)
- Leah V Schaffer
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - Trisha Tucholski
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - Michael R Shortreed
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - Ying Ge
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States.,Department of Cell and Regenerative Biology , University of Wisconsin-Madison , Madison , Wisconsin 53705 , United States.,Human Proteomics Program , University of Wisconsin-Madison , Madison , Wisconsin 53705 , United States
| | - Lloyd M Smith
- Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
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14
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Chu SH, Huang M, Kelly RS, Benedetti E, Siddiqui JK, Zeleznik OA, Pereira A, Herrington D, Wheelock CE, Krumsiek J, McGeachie M, Moore SC, Kraft P, Mathé E, Lasky-Su J. Integration of Metabolomic and Other Omics Data in Population-Based Study Designs: An Epidemiological Perspective. Metabolites 2019; 9:E117. [PMID: 31216675 PMCID: PMC6630728 DOI: 10.3390/metabo9060117] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 06/12/2019] [Accepted: 06/14/2019] [Indexed: 12/30/2022] Open
Abstract
It is not controversial that study design considerations and challenges must be addressed when investigating the linkage between single omic measurements and human phenotypes. It follows that such considerations are just as critical, if not more so, in the context of multi-omic studies. In this review, we discuss (1) epidemiologic principles of study design, including selection of biospecimen source(s) and the implications of the timing of sample collection, in the context of a multi-omic investigation, and (2) the strengths and limitations of various techniques of data integration across multi-omic data types that may arise in population-based studies utilizing metabolomic data.
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Affiliation(s)
- Su H Chu
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Mengna Huang
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Rachel S Kelly
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Elisa Benedetti
- Institute for Computational Biomedicine, Englander Institute for Precision Medicine, Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10021, USA.
| | - Jalal K Siddiqui
- Department of Biomedical Informatics, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
| | - Oana A Zeleznik
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Alexandre Pereira
- Department of Genetics and Molecular Medicine, University of Sao Paulo Medical School, Sao Paulo 01246-903, Brazil.
| | - David Herrington
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27101, USA.
| | - Craig E Wheelock
- Division of Physiological Chemistry 2, Department of Medical Biochemistry and Biophysics, Karolinska Institute, 171 77 Stockholm, Sweden.
| | - Jan Krumsiek
- Institute for Computational Biomedicine, Englander Institute for Precision Medicine, Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10021, USA.
| | - Michael McGeachie
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Steven C Moore
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD 20850, USA.
| | - Peter Kraft
- Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA.
| | - Ewy Mathé
- Department of Biomedical Informatics, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
| | - Jessica Lasky-Su
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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15
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Schaffer LV, Millikin RJ, Miller RM, Anderson LC, Fellers RT, Ge Y, Kelleher NL, LeDuc RD, Liu X, Payne SH, Sun L, Thomas PM, Tucholski T, Wang Z, Wu S, Wu Z, Yu D, Shortreed MR, Smith LM. Identification and Quantification of Proteoforms by Mass Spectrometry. Proteomics 2019; 19:e1800361. [PMID: 31050378 PMCID: PMC6602557 DOI: 10.1002/pmic.201800361] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/07/2019] [Indexed: 12/29/2022]
Abstract
A proteoform is a defined form of a protein derived from a given gene with a specific amino acid sequence and localized post-translational modifications. In top-down proteomic analyses, proteoforms are identified and quantified through mass spectrometric analysis of intact proteins. Recent technological developments have enabled comprehensive proteoform analyses in complex samples, and an increasing number of laboratories are adopting top-down proteomic workflows. In this review, some recent advances are outlined and current challenges and future directions for the field are discussed.
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Affiliation(s)
- Leah V Schaffer
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Robert J Millikin
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Rachel M Miller
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Lissa C Anderson
- Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Ryan T Fellers
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Cell and Regenerative Biology and Human Proteomics Program, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Neil L Kelleher
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
- Department of Chemistry and Molecular Biosciences and the Division of Hematology and Oncology, Northwestern University, Evanston, IL, 60208, USA
| | - Richard D LeDuc
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
| | - Xiaowen Liu
- Department of BioHealth Informatics, Indiana University-Purdue University, Indianapolis, IN, 46202, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Samuel H Payne
- Department of Biology, Brigham Young University, Provo, UT, 84602
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Paul M Thomas
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
| | - Trisha Tucholski
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Zhijie Wu
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Michael R Shortreed
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
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16
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Berg P, McConnell EW, Hicks LM, Popescu SC, Popescu GV. Evaluation of linear models and missing value imputation for the analysis of peptide-centric proteomics. BMC Bioinformatics 2019; 20:102. [PMID: 30871482 PMCID: PMC6419331 DOI: 10.1186/s12859-019-2619-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Several methods to handle data generated from bottom-up proteomics via liquid chromatography-mass spectrometry, particularly for peptide-centric quantification dealing with post-translational modification (PTM) analysis like reversible cysteine oxidation are evaluated. The paper proposes a pipeline based on the R programming language to analyze PTMs from peptide-centric label-free quantitative proteomics data. RESULTS Our methodology includes variance stabilization, normalization, and missing data imputation to account for the large dynamic range of PTM measurements. It also corrects biases from an enrichment protocol and reduces the random and systematic errors associated with label-free quantification. The performance of the methodology is tested by performing proteome-wide differential PTM quantitation using linear models analysis (limma). We objectively compare two imputation methods along with significance testing when using multiple-imputation for missing data. CONCLUSION Identifying PTMs in large-scale datasets is a problem with distinct characteristics that require new methods for handling missing data imputation and differential proteome analysis. Linear models in combination with multiple-imputation could significantly outperform a t-test-based decision method.
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Affiliation(s)
- Philip Berg
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS, USA.,Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS, USA
| | - Evan W McConnell
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Leslie M Hicks
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Sorina C Popescu
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Mississippi State, MS, USA
| | - George V Popescu
- Institute for Genomics, Biocomputing and Biotechnology, Mississippi State University, Mississippi State, MS, USA. .,The National Institute for Laser, Plasma & Radiation Physics, Bucharest, Romania.
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17
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Foreman DJ, Dziekonski ET, McLuckey SA. Maximizing Selective Cleavages at Aspartic Acid and Proline Residues for the Identification of Intact Proteins. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:34-44. [PMID: 29713964 PMCID: PMC6207472 DOI: 10.1007/s13361-018-1965-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 04/06/2018] [Accepted: 04/09/2018] [Indexed: 05/03/2023]
Abstract
A new approach for the identification of intact proteins has been developed that relies on the generation of relatively few abundant products from specific cleavage sites. This strategy is intended to complement standard approaches that seek to generate many fragments relatively non-selectively. Specifically, this strategy seeks to maximize selective cleavage at aspartic acid and proline residues via collisional activation of precursor ions formed via electrospray ionization (ESI) under denaturing conditions. A statistical analysis of the SWISS-PROT database was used to predict the number of arginine residues for a given intact protein mass and predict a m/z range where the protein carries a similar charge to the number of arginine residues thereby enhancing cleavage at aspartic acid residues by limiting proton mobility. Cleavage at aspartic acid residues is predicted to be most favorable in the m/z range of 1500-2500, a range higher than that normally generated by ESI at low pH. Gas-phase proton transfer ion/ion reactions are therefore used for precursor ion concentration from relatively high charge states followed by ion isolation and subsequent generation of precursor ions within the optimal m/z range via a second proton transfer reaction step. It is shown that the majority of product ion abundance is concentrated into cleavages C-terminal to aspartic acid residues and N-terminal to proline residues for ions generated by this process. Implementation of a scoring system that weights both ion fragment type and ion fragment area demonstrated identification of standard proteins, ranging in mass from 8.5 to 29.0 kDa. Graphical Abstract ᅟ.
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Affiliation(s)
- David J Foreman
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA
| | | | - Scott A McLuckey
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, IN, 47907-2084, USA.
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18
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Wang H, Leeming MG, Ho J, Donald WA. Origin and Prediction of Highly Specific Bond Cleavage Sites in the Thermal Activation of Intact Protein Ions. Chemistry 2018; 25:823-834. [DOI: 10.1002/chem.201804668] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Huixin Wang
- School of Chemistry University of New South Wales Sydney New South Wales Australia
| | - Michael G. Leeming
- School of Chemistry, Bio21 Institute of Molecular Science and Biotechnology The University of Melbourne Melbourne Victoria Australia
| | - Junming Ho
- School of Chemistry University of New South Wales Sydney New South Wales Australia
| | - William A. Donald
- School of Chemistry University of New South Wales Sydney New South Wales Australia
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19
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Paik YK, Lane L, Kawamura T, Chen YJ, Cho JY, LaBaer J, Yoo JS, Domont G, Corrales F, Omenn GS, Archakov A, Encarnación-Guevara S, Lui S, Salekdeh GH, Cho JY, Kim CY, Overall CM. Launching the C-HPP neXt-CP50 Pilot Project for Functional Characterization of Identified Proteins with No Known Function. J Proteome Res 2018; 17:4042-4050. [PMID: 30269496 PMCID: PMC6693327 DOI: 10.1021/acs.jproteome.8b00383] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
An important goal of the Human Proteome Organization (HUPO) Chromosome-centric Human Proteome Project (C-HPP) is to correctly define the number of canonical proteins encoded by their cognate open reading frames on each chromosome in the human genome. When identified with high confidence of protein evidence (PE), such proteins are termed PE1 proteins in the online database resource, neXtProt. However, proteins that have not been identified unequivocally at the protein level but that have other evidence suggestive of their existence (PE2-4) are termed missing proteins (MPs). The number of MPs has been reduced from 5511 in 2012 to 2186 in 2018 (neXtProt 2018-01-17 release). Although the annotation of the human proteome has made significant progress, the "parts list" alone does not inform function. Indeed, 1937 proteins representing ∼10% of the human proteome have no function either annotated from experimental characterization or predicted by homology to other proteins. Specifically, these 1937 "dark proteins" of the so-called dark proteome are composed of 1260 functionally uncharacterized but identified PE1 proteins, designated as uPE1, plus 677 MPs from categories PE2-PE4, which also have no known or predicted function and are termed uMPs. At the HUPO-2017 Annual Meeting, the C-HPP officially adopted the uPE1 pilot initiative, with 14 participating international teams later committing to demonstrate the feasibility of the functional characterization of large numbers of dark proteins (CP), starting first with 50 uPE1 proteins, in a stepwise chromosome-centric organizational manner. The second aim of the feasibility phase to characterize protein (CP) functions of 50 uPE1 proteins, termed the neXt-CP50 initiative, is to utilize a variety of approaches and workflows according to individual team expertise, interest, and resources so as to enable the C-HPP to recommend experimentally proven workflows to the proteome community within 3 years. The results from this pilot will not only be the cornerstone of a larger characterization initiative but also enhance understanding of the human proteome and integrated cellular networks for the discovery of new mechanisms of pathology, mechanistically informative biomarkers, and rational drug targets.
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Affiliation(s)
- Young-Ki Paik
- Yonsei Proteome Research Center and Department of Integrative Omics, Yonsei University, Sudaemoon-ku, Seoul, Korea
| | - Lydie Lane
- CALIPHO group, Swiss Institute of Bioinformatics & Department of Microbiology and Molecular medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Takeshi Kawamura
- Proteomics Laboratory, Isotope Science Center, The University of Tokyo, Bunkyo-Ku, Tokyo 113-0032 Japan
| | - Yu-Ju Chen
- Institute of Chemistry Academia Sinica, 128 Academia Road Sec. 2, Nankang Taipei 115 Taiwan
| | - Je-Yoel Cho
- Research Institute for Veterinary Science, College of Veterinary Medicine, Seoul University, 1 Gwanak-, Gwanak-gu, 151-742 Seoul, South Korea
| | - Joshua LaBaer
- McAllister Ave. Arizona State University, Tempe, Arizona, 85287-5001, USA
| | - Jong Shin Yoo
- Division of Mass Spectrometry Research, Korea Basic Science Institute, Ochang, Korea
| | - Gilberto Domont
- Federal University of Rio de Janeiro Institute of Chemistry, Rio de Janeiro, RJ Brazil
| | - Fernando Corrales
- Functional Proteomics Laboratory National Center of Biotechnology, CSIC 28049 Madrid, Spain
| | - Gilbert S. Omenn
- Center for Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan 48109-2218, United States
| | | | | | - Siqi Lui
- BGI-Shenzhen, Beishan Industrial Zone, Yantian District, Shenzhen, 518083, China
| | - Ghasem Hosseini Salekdeh
- Department of Molecular Systems Biology, Royan Institute for Stem Cell Biology and Technology, 1665659911, Tehran, Iran
- Department of Molecular Sciences, Macquarie University, Sydney, Australia
| | - Jin-Young Cho
- Yonsei Proteome Research Center and Department of Integrative Omics, Yonsei University, Sudaemoon-ku, Seoul, Korea
| | - Chae-Yeon Kim
- Yonsei Proteome Research Center and Department of Integrative Omics, Yonsei University, Sudaemoon-ku, Seoul, Korea
| | - Christopher M. Overall
- Centre for Blood Research, Departments of Oral Biological & Medical Sciences, and Biochemistry & Molecular Biology, Faculty of Dentistry, University of British Columbia, Vancouver, Canada
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20
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Schaffer LV, Rensvold JW, Shortreed MR, Cesnik AJ, Jochem A, Scalf M, Frey BL, Pagliarini DJ, Smith LM. Identification and Quantification of Murine Mitochondrial Proteoforms Using an Integrated Top-Down and Intact-Mass Strategy. J Proteome Res 2018; 17:3526-3536. [PMID: 30180576 PMCID: PMC6201694 DOI: 10.1021/acs.jproteome.8b00469] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The development of effective strategies for the comprehensive identification and quantification of proteoforms in complex systems is a critical challenge in proteomics. Proteoforms, the specific molecular forms in which proteins are present in biological systems, are the key effectors of biological function. Thus, knowledge of proteoform identities and abundances is essential to unraveling the mechanisms that underlie protein function. We recently reported a strategy that integrates conventional top-down mass spectrometry with intact-mass determinations for enhanced proteoform identifications and the elucidation of proteoform families and applied it to the analysis of yeast cell lysate. In the present work, we extend this strategy to enable quantification of proteoforms, and we examine changes in the abundance of murine mitochondrial proteoforms upon differentiation of mouse myoblasts to myotubes. The integrated top-down and intact-mass strategy provided an increase of ∼37% in the number of identified proteoforms compared to top-down alone, which is in agreement with our previous work in yeast; 1779 unique proteoforms were identified using the integrated strategy compared to 1301 using top-down analysis alone. Quantitative comparison of proteoform differences between the myoblast and myotube cell types showed 129 observed proteoforms exhibiting statistically significant abundance changes (fold change >2 and false discovery rate <5%).
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Affiliation(s)
- Leah V. Schaffer
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | | | - Michael R. Shortreed
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Anthony J. Cesnik
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Adam Jochem
- Morgridge Institute for Research, Madison, WI 53715, USA
| | - Mark Scalf
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Brian L. Frey
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - David J. Pagliarini
- Morgridge Institute for Research, Madison, WI 53715, USA
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Lloyd M. Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, WI 53706, USA
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21
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Kalu Appulage D, Wang EH, Figard BJ, Schug KA. An integrated multipath liquid chromatography-mass spectrometry system for the simultaneous preparation, separation, and detection of proteins and small molecules. J Sep Sci 2018; 41:2702-2709. [PMID: 29676850 DOI: 10.1002/jssc.201800298] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/10/2018] [Accepted: 04/11/2018] [Indexed: 11/08/2022]
Abstract
A multipath liquid chromatography with mass spectrometry instrument was constructed with the help of restricted access media to online segregate small and large molecules. This liquid chromatography system was custom built with five pumps and three two-position six-port valves to control the flow in a multipath system for the simultaneous analysis of small molecules and proteins. On separate chromatographic channels, small molecules trapped and proteins excluded from the online restricted access media were analyzed downstream using high-efficiency columns and a triple quadrupole mass spectrometer. A model sample, which included five proteins and 22 small molecules with different physicochemical properties, was used to evaluate the system. Following injection, the complete multipath separation and detection was performed in 22 min. Protein exclusion by the restricted access media was not quantitative. Four commercial trap columns were evaluated for their exclusion efficiency toward the proteins. Exclusion efficiency varied from <50% to only a maximum of 75% exclusion across the trap columns tested. An attempt was made to optimize the exclusion efficiency using different flow rates, flow rate gradients, and different additives both in the sample and the mobile phases. Protein exclusion was still erratic and generally nonquantitative.
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Affiliation(s)
- Dananjaya Kalu Appulage
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA
| | - Evelyn H Wang
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA
| | | | - Kevin A Schug
- Department of Chemistry and Biochemistry, The University of Texas at Arlington, Arlington, TX, USA
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22
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Cesnik AJ, Shortreed MR, Schaffer LV, Knoener RA, Frey BL, Scalf M, Solntsev SK, Dai Y, Gasch AP, Smith LM. Proteoform Suite: Software for Constructing, Quantifying, and Visualizing Proteoform Families. J Proteome Res 2017; 17:568-578. [PMID: 29195273 DOI: 10.1021/acs.jproteome.7b00685] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We present an open-source, interactive program named Proteoform Suite that uses proteoform mass and intensity measurements from complex biological samples to identify and quantify proteoforms. It constructs families of proteoforms derived from the same gene, assesses proteoform function using gene ontology (GO) analysis, and enables visualization of quantified proteoform families and their changes. It is applied here to reveal systemic proteoform variations in the yeast response to salt stress.
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Affiliation(s)
- Anthony J Cesnik
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Michael R Shortreed
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Leah V Schaffer
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Rachel A Knoener
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Brian L Frey
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Mark Scalf
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Stefan K Solntsev
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Yunxiang Dai
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Audrey P Gasch
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
| | - Lloyd M Smith
- Department of Chemistry, ‡Laboratory of Genetics, and §Genome Center of Wisconsin, University of Wisconsin-Madison , Madison, Wisconsin 53706, United States
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