Analysis of Lipid Experiments (ALEX): A Software Framework for Analysis of High-Resolution Shotgun Lipidomics Data

Global lipidomics analysis across large sample sizes produces high-content datasets that require dedicated software tools supporting lipid identification and quantification, efficient data management and lipidome visualization. Here we present a novel software-based platform for streamlined data processing, management and visualization of shotgun lipidomics data acquired using high-resolution Orbitrap mass spectrometry. The platform features the ALEX framework designed for automated identification and export of lipid species intensity directly from proprietary mass spectral data files, and an auxiliary workflow using database exploration tools for integration of sample information, computation of lipid abundance and lipidome visualization. A key feature of the platform is the organization of lipidomics data in ”database table format” which provides the user with an unsurpassed flexibility for rapid lipidome navigation using selected features within the dataset. To demonstrate the efficacy of the platform, we present a comparative neurolipidomics study of cerebellum, hippocampus and somatosensory barrel cortex (S1BF) from wild-type and knockout mice devoid of the putative lipid phosphate phosphatase PRG-1 (plasticity related gene-1). The presented framework is generic, extendable to processing and integration of other lipidomic data structures, can be interfaced with post-processing protocols supporting statistical testing and multivariate analysis, and can serve as an avenue for disseminating lipidomics data within the scientific community. The ALEX software is available at www.msLipidomics.info.

[1]  Matej Oresic,et al.  Informatics and computational strategies for the study of lipids. , 2008, Molecular bioSystems.

[2]  Stefan R Bornstein,et al.  A novel informatics concept for high-throughput shotgun lipidomics based on the molecular fragmentation query language , 2011, Genome Biology.

[3]  M. A. Surma,et al.  Flexibility of a Eukaryotic Lipidome – Insights from Yeast Lipidomics , 2012, PloS one.

[4]  J. O'brien,et al.  Lipid composition of the normal human brain: gray matter, white matter, and myelin. , 1965, Journal of lipid research.

[5]  Helmut Grubmüller,et al.  Molecular Anatomy of a Trafficking Organelle , 2006, Cell.

[6]  Suzanne Eaton,et al.  Effects of diet and development on the Drosophila lipidome , 2012, Molecular systems biology.

[7]  Christer S. Ejsing,et al.  Segregation of sphingolipids and sterols during formation of secretory vesicles at the trans-Golgi network , 2009, The Journal of cell biology.

[8]  Carmen Birchmeier,et al.  Synaptic PRG-1 Modulates Excitatory Transmission via Lipid Phosphate-Mediated Signaling , 2009, Cell.

[9]  A. Shevchenko,et al.  Top-down lipidomic screens by multivariate analysis of high-resolution survey mass spectra. , 2007, Analytical chemistry.

[10]  Eoin Fahy,et al.  A Mouse Macrophage Lipidome*♦ , 2010, The Journal of Biological Chemistry.

[11]  M. D. Leavell,et al.  Fatty acid analysis tool (FAAT): An FT-ICR MS lipid analysis algorithm. , 2006, Analytical chemistry.

[12]  Martin Hermansson,et al.  Software tools for analysis of mass spectrometric lipidome data. , 2006, Analytical chemistry.

[13]  Gerd Schmitz,et al.  High throughput quantification of cholesterol and cholesteryl ester by electrospray ionization tandem mass spectrometry (ESI-MS/MS). , 2006, Biochimica et biophysica acta.

[14]  G. van Meer,et al.  Cellular lipidomics , 2005, The EMBO journal.

[15]  Christer S. Ejsing,et al.  Accumulation of raft lipids in T‐cell plasma membrane domains engaged in TCR signalling , 2009, The EMBO journal.

[16]  Stefan R Bornstein,et al.  Shotgun lipidomics on a LTQ Orbitrap mass spectrometer by successive switching between acquisition polarity modes. , 2012, Journal of mass spectrometry : JMS.

[17]  Christer S. Ejsing,et al.  Charting molecular composition of phosphatidylcholines by fatty acid scanning and ion trap MS3 fragmentation Published, JLR Papers in Press, August 16, 2003. DOI 10.1194/jlr.D300020-JLR200 , 2003, Journal of Lipid Research.

[18]  G. Hübner,et al.  lipID--a software tool for automated assignment of lipids in mass spectra. , 2009, Journal of mass spectrometry : JMS.

[19]  Ivan Bratko,et al.  Microarray data mining with visual programming , 2005, Bioinform..

[20]  A. Shevchenko,et al.  Lipidomics: coming to grips with lipid diversity , 2010, Nature Reviews Molecular Cell Biology.

[21]  Haowei Song,et al.  Algorithm for processing raw mass spectrometric data to identify and quantitate complex lipid molecular species in mixtures by data-dependent scanning and fragment ion database searching , 2007, Journal of the American Society for Mass Spectrometry.

[22]  D. Selkoe,et al.  Lipidomic profiling in mouse brain reveals differences between ages and genders, with smaller changes associated with α‐synuclein genotype , 2009, Journal of neurochemistry.

[23]  Markus R Wenk,et al.  Comparative Lipidomic Analysis of Mouse and Human Brain with Alzheimer Disease* , 2011, The Journal of Biological Chemistry.

[24]  Juan Antonio Vizcaíno,et al.  Shorthand notation for lipid structures derived from mass spectrometry , 2013, Journal of Lipid Research.

[25]  Christer S. Ejsing,et al.  Global analysis of the yeast lipidome by quantitative shotgun mass spectrometry , 2009, Proceedings of the National Academy of Sciences.

[26]  Takao Shimizu,et al.  A shotgun tandem mass spectrometric analysis of phospholipids with normal-phase and/or reverse-phase liquid chromatography/electrospray ionization mass spectrometry. , 2005, Rapid communications in mass spectrometry : RCM.

[27]  Ole N Jensen,et al.  Quantitative profiling of PE, MMPE, DMPE, and PC lipid species by multiple precursor ion scanning: a tool for monitoring PE metabolism. , 2011, Biochimica et biophysica acta.

[28]  W. Lehmann,et al.  Determination of cholesterol at the low picomole level by nano-electrospray ionization tandem mass spectrometry. , 1999, Journal of lipid research.

[29]  Hans-Georg Kräusslich,et al.  The HIV lipidome: a raft with an unusual composition. , 2006, Proceedings of the National Academy of Sciences of the United States of America.

[30]  Kai Simons,et al.  Automated identification and quantification of glycerophospholipid molecular species by multiple precursor ion scanning. , 2006, Analytical chemistry.

[31]  Theodoros N. Arvanitis,et al.  Dynamic range and mass accuracy of wide-scan direct infusion nanoelectrospray fourier transform ion cyclotron resonance mass spectrometry-based metabolomics increased by the spectral stitching method. , 2007, Analytical chemistry.

[32]  Kai Simons,et al.  Membrane lipidome of an epithelial cell line , 2011, Proceedings of the National Academy of Sciences.

[33]  Christer S. Ejsing,et al.  Lipid profiling by multiple precursor and neutral loss scanning driven by the data-dependent acquisition. , 2006, Analytical chemistry.

[34]  C. Glass,et al.  A comprehensive classification system for lipids. , 2005, Journal of lipid research.

[35]  Christer S. Ejsing,et al.  Orm family proteins mediate sphingolipid homeostasis , 2010, Nature.

[36]  Xianlin Han,et al.  Multi-dimensional mass spectrometry-based shotgun lipidomics and novel strategies for lipidomic analyses. , 2012, Mass spectrometry reviews.