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isobar - R package for iTRAQ and TMT proteomics data

isobar provides methods for preprocessing, normalization, and
report generation for the analysis of proteomics data generated by Mass spectrometers using isobaric peptide tags, such as iTRAQ and TMT. PDF and Excel reports can automatically be generated based on a configuration file. Include modules for validating and integrating data focussing on post-translational protein modifications (isobar-PTM).

Installation

The official Bioconductor version can be found at http://bioconductor.org/packages/release/bioc/html/isobar.html

To install isobar from Bioconductor, call

## try http:// if https:// URLs are not supported
source("https://bioconductor.org/biocLite.R")
biocLite("isobar")

To install the development version of isobar, the easiest way is using the devtools package:

## install.package("devtools") # if you do not have the devtools package
devtools::install_github("fbreitwieser/isobar")

The following packages are suggested for some uses in isobar, and maybe should be installed as well: MSnbase, OrgMassSpecR, biomaRt, Hmisc, gplots and limma.

References

  • Florian P. Breitwieser, André Müller, Loïc Dayon, Thomas Köcher, Alexandre Hainard, Peter Pichler, Ursula Schmidt-Erfurth, Giulio Superti-Furga, Jean-Charles Sanchez, Karl Mechtler, Keiryn L. Bennett, and Jacques Colinge (June 2011). “General statistical modeling of data from protein relative expression isobaric tags.” In: J Proteome Res

10.6, pp. 2758–2766

  • Florian P. Breitwieser and Jacques Colinge (Sept. 2013). “Isobar(PTM): a software tool for the quantitative analysis of post-translationally modified proteins.” eng. In: J Proteomics 90, pp. 77–84

For publications citing isobar please see Google scholar for isobar and isobar PTM.

Many thanks to Alexey Stukalov, Xavier Robin and Florent Gluck who contributed to the development of the package.

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Version

Version

1.18.0

License

LGPL-2

Issues

Pull Requests

Stars

Forks

Maintainer

Florian P Breitwieser

Last Published

February 15th, 2017

Functions in isobar (1.18.0)

correct.peptide.ratios

Correct peptide ratios with protein ratios from a separate experiment.
isobar-plots

IBSpectra plots
shared.ratios.sign

Plot and get significantly shared ratios.
proteinInfo-methods

Methods for Function proteinInfo
reporter.protein-methods

Get reporter protein group identifier for protein group identifier
ProteinGroup-class

ProteinGroup objects
calculate.dNSAF

dNSAF approximate abundance calculations.
getPtmInfo

Get PTM site information for idenfied proteins from public databases.
distr-methods

Functions for distribution calculations
calc.delta.score

Calculate Delta Score from Ion Score
number.ranges

Helper function to transform number lists to ranges
maplot.protein

Ratio intensity plot for individual proteins
observedKnownSites

Observed modification sites.
subsetIBSpectra

Subset IBSpectra objects
Tlsd-class

Class "Tlsd"
Protein and peptide ratio calculation and summarization

Calculating and Summarizing Protein and Peptide Ratios
isobar-import

Loading data into IBSpectra objects using readIBSpectra
Isobar util functions

Isobar util functions
getPhosphoRSProbabilities

Generate input files for PhosphoRS, call it, and get modification site probabilities
sanitize

Helper function for LaTeX export
writeHscoreData

Write identifications into a format suitable for Hscore.
calcPeptidePosition

Recalculate peptide start positions based on protein sequence
ratiosReshapeWide

Reshape output of proteinRatios into wide format
isobar.data

Isobar Data packages
isobar-package

Analysis and quantitation of isobarically tagged MSMS proteomics data
getPeptideModifContext

Get context of modification
TlsParameter-class

Class "TlsParameter"
fit distributions

Fit weighted and unweighted Cauchy and Normal distributions
shared.ratios

Shared ratio calculation
IBSpectra-class

IBSpectra Class for Isobarically Tagged Quantitative MS Proteomics Data
calculate.emPAI

emPAI approximate abundance calculations.
human.protein.names

Info on proteins
calculate-pvalues

Calculate and Adjust Ratio and Sample p-values.
specificities

Peptide specificities
peptide.count

Peptide counts, spectral counts and sequence coverage for ProteinGroup objects.
NoiseModel-class

NoiseModel objects
isobar-preprocessing

IBSpectra preprocessing
spectra.count2

Spectral count for peptides and proteins in ProteinGroup objects.
isobar-analysis

IBSpectra analysis: Protein and peptide ratio calculation
writeIBSpectra

Write IBSpectra file as CSV in a format readable by readIBSpectra.
isobar-reports

Isobar reports
groupMemberPeptides

Peptide info for protein group members
IBSpectra.log

Log functions for IBSpectra objects
proteinNameAndDescription

Get protein gene names and description from protein info of protein group.