Package 'spikeLI'

Title: Affymetrix Spike-in Langmuir Isotherm Data Analysis Tool
Description: SpikeLI is a package that performs the analysis of the Affymetrix spike-in data using the Langmuir Isotherm. The aim of this package is to show the advantages of a physical-chemistry based analysis of the Affymetrix microarray data compared to the traditional methods. The spike-in (or Latin square) data for the HGU95 and HGU133 chipsets have been downloaded from the Affymetrix web site. The model used in the spikeLI package is described in details in E. Carlon and T. Heim, Physica A 362, 433 (2006).
Authors: Delphine Baillon, Paul Leclercq <[email protected]>, Sarah Ternisien, Thomas Heim, Enrico Carlon <[email protected]>
Maintainer: Enrico Carlon <[email protected]>
License: GPL-2
Version: 2.65.0
Built: 2024-07-25 04:42:54 UTC
Source: https://github.com/bioc/spikeLI

Help Index


Analysis of Affymetrix spike-in data (HGU95 and HGU133 Latin square) using the Langmuir Isotherm.

Description

spikeLI performs a series of analysis of Affymetrix spike-in data using inputs from physical-chemistry. It illustrates the advantages of such approach in determining expression levels and in identifying outliers compared to other methods. The analysis so far is restricted to spike-in genes. It will be extended to a generic CEL file. spikeLI does not require affy (and it is independent of any other bioconductor packages) as it reads spike-in data from a data frame variable hgu which is contained in the package.

Details

Package: spikeLI
Type: Package
Version: 1.0
Date: 2006-05-05
License: GNU Public License

The package contains three basic functions: - Ivsc plot intensities as function of spike-in concentration for a fixed probe. - IvsDG plot intensities as function of affinity for a given probe set at fixed concentration. - collapse plot of intensities both as a function of concentration and affinities.

Author(s)

Delphine Baillon, Paul Leclercq, Sarah Ternisien, Thomas Heim and Enrico Carlon

Maintainer: Enrico Carlon <[email protected]>

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

collapse, Ivsc, IvsDG, hgu, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH , SPIKE_IN95


Data collapse of all concentrations into a single graph

Description

This function takes as input one or more (up to four) probe sets of the Latin square spike-in data and produces collapse plots. A collapse plot contains data of different concentrations into a single graph. The user can compare in how far the data follows the predicted Langmuir behavior which is also given in the plot. Two models are compared: the basic Langmuir Isotherm and the Langmuir Isotherm with hybridization in solution.

Usage

collapse(probe_set, param = "NULL", probes = "NULL", output = "NULL", filename = "NULL")

Arguments

probe_set

This has to take the value of a probe set

param

In input one or more probe sets can be given

probes

A vector containing the probes

output

"PS" output on a postscript file

filename

the file in which collapses are given

Author(s)

Delphine Baillon, Paul Leclercq, Sarah Ternisien, Thomas Heim and Enrico Carlon

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, hgu, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

## You may display the matched intensities of a Probe-Set according to the Delta-G value
     collapse("1091_at")

## You may restrict the value to the Perfect match or mis-matches
     collapse("1091_at","PM")

## You may restrict the values risplayed for only a number of probes
     collapse("1091_at",probes=c(1,9))

## You may output the graphs to a postscript file
     collapse("1091_at",output="PS",filename="outfile.ps")

## You may display up to 4 probe-sets in the same window
     collapse(c("1091_at","37777_at",SPIKE_INA[1:2]))

## You can also use the values of the probe-sets contained in one of the Vectors of Human, Bacteria, 
## or Artificial Probe-sets
     collapse(SPIKE_INH)

Concentration 95

Description

This datasets contains the values of the latine square matrix for the hgu133 Affymetrix Microarrays

Usage

data(conc133)

Format

The format is: num [1:14] 0 0.125 0.25 0.5 1 2 4 8 16 32 ...

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

data(conc133)

Concentration 95

Description

This datasets contains the values of the latine square matrix for the hgu95 Affymetrix Microarrays

Usage

data(conc95)

Format

The format is: num [1:14] 0 0.25 0.5 1 2 4 8 16 32 64 ...

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

data(conc95)

Selected Probe Set data

Description

This selected probe sets information contains the sequence of the selected probe sets, as well as the match and mismatch onformation and Delta G value required for the langmuir analysis

Usage

data(hgu)

Format

A data frame with 11452 observations on the following 9 variables.

Probe.Set.Name

Name of probe set

conc

a numeric vector

Ipm

a numeric vector

Imm

a numeric vector

Seq

DNA Sequence of the probe

DGpm

DG value of perfect match of the probe

DGmm

Delta G value of the mismatch of the probe

DGRNA

Delta G value of the RNA

FILE

a factor with levels HGU133 HGU95

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

data(hgu)
## maybe str(hgu) ; plot(hgu) ...

Plot of intensity vs. concentration for given probes

Description

The function Ivsc plots intensity as a function of a concentration for a given probe in the spike-in Latin square experiments. It also peforms a non-linear data fit (using the package nls in the R-package stats) of the experimental data using the Langmuir Isotherm: I = I0 + Ac/(K+c) Solid and dashed lines are best fits according to this formula. Imax in the plot are given by Imax=I0+A, ie the asymptotic intensity in the limit of c to infinity.

Usage

Ivsc(probe_set, probe = "NULL", outfile = "NULL")

Arguments

probe_set

Probe set number of the probe set analyzed

probe

Integer giving the probe number (if not give the probe 1 is selected)

outfile

output the plotted data to a postscript file

Warning

Some probes have an irregular behavior and the non-linear square fit does not converge.

Author(s)

Delphine Baillon, Paul Leclercq, Sarah Ternisien, Thomas Heim and Enrico Carlon

Maintainer: Enrico Carlon <[email protected]>

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

collapse, IvsDG, hgu, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

Ivsc("37777_at",4)

Plot Intensity as function of the affinity for a given probe set at fixed concentration.

Description

IvsDG plots intensity vs affinity (or free energy) for a probe set at a given concentration. The outcome is compared with the prediction from the Langmuir isotherm at that concentration. Two graphs are shown: on the left intensity vs. probe number for PM (blue) and MM (red); on the right the same value plotted as function of the affinities. The black line is the Langmuir Isotherm at the given concentration. The two green lines correspond to concentrations fourfold higher and lower compared to the given one.

Usage

IvsDG(probe_set, conc, outfile = "NULL")

Arguments

probe_set

Probe set number of the probe set analyzed

conc

Concentration value

outfile

"PS" output on a postscript file

Author(s)

Delphine Baillon, Paul Leclercq, Sarah Ternisien, Thomas Heim and Enrico Carlon

Maintainer: Enrico Carlon <[email protected]>

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, collapse, hgu, SPIKE_IN, SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

data(hgu)
     IvsDG("1024_at",64)

Spike-in Probe-Set Names

Description

This dataset contains the names of the Probe-Sets contained in the HGU dataset

Usage

data(SPIKE_IN)

Format

A string containing the name of the genes

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, collapse, hgu, SPIKE_INA , SPIKE_INB, SPIKE_INH, SPIKE_IN95

Examples

## you can first check if the data matches the predicted hybridisation value according to the langmuir 
## value, from the intensity versus the concentration value
Ivsc(SPIKE_IN[3])

## you can then plot the value of the Intensity of the probe with the predicted value of the hybridisation
## according to the Delta G, value
IvsDG(SPIKE_IN[5],64)

## The collapse function will finally plot all the values of the probe set according to 
## the langmuir absorption theory

collapse(SPIKE_IN[2])

## By comparing the matched value and the mismatches, you will be able to identify errors which 
## could have done while sampling the data, or if the error happens repeatedly this will show errors 
## which will have happened while sequencing old data.

set of spike-in genes contained in the HGU95 dataset

Description

This dataset contains a set of gene names contained in the HGU95 dataset

Usage

data(SPIKE_IN95)

Format

The set of spike-in gene names contained in the HGU dataset

Source

This data is experimental data extracted from the publicly available HGU dataset

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, hgu , SPIKE_INA, SPIKE_INB, SPIKE_INH

Examples

## you can first check if the data matches the predicted hybridisation value according to the langmuir 
## value, from the intensity versus the concentration value
Ivsc(SPIKE_IN95[1])

## you can then plot the value of the Intensity of the probe with the predicted value of the hybridisation
## according to the Delta G, value
IvsDG(SPIKE_IN95[4],128)

## The collapse function will finally plot all the values of the probe set according to 
## the langmuir absorption theory

collapse(SPIKE_IN95[2])

## By comparing the matched value and the mismatches, you will be able to identify errors which 
## could have done while sampling the data, or if the error happens repeatedly this will show errors 
## which will have happened while sequencing old data.

Artificial Spike-in probesets

Description

This dataset contains the names of the probesets contained in the hgu dataset

Usage

data(SPIKE_INA)

Format

This dataset contains a set of String containing the names of the Artificial genes contained in the HGU dataset

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, hgu , SPIKE_INB, SPIKE_INH

Examples

## you can first check if the data matches the predicted hybridisation value according to the langmuir 
## value, from the intensity versus the concentration value
Ivsc(SPIKE_INA[1])

## you can then plot the value of the Intensity of the probe with the predicted value of the hybridisation
## according to the Delta G, value
IvsDG(SPIKE_INA[4],128)

## The collapse function will finally plot all the values of the probe set according to 
## the langmuir absorption theory

collapse(SPIKE_INA[2])

## By comparing the matched value and the mismatches, you will be able to identify errors which 
## could have done while sampling the data, or if the error happens repeatedly this will show errors 
## which will have happened while sequencing old data.

Bacteria Spike-in probeset names

Description

This dataset contains the names of the Bacteria probe-sets contained in the HGU dataset

Usage

data(SPIKE_INB)

Format

names of the Bacteria probe-sets contained in the HGU dataset

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, hgu , SPIKE_INA, SPIKE_INH

Examples

## you can first check if the data matches the predicted hybridisation value according to the langmuir 
## value, from the intensity versus the concentration value
Ivsc(SPIKE_INB[3])

## you can then plot the value of the Intensity of the probe with the predicted value of the hybridisation
## according to the Delta G, value
IvsDG(SPIKE_INB[4],64)

## The collapse function will finally plot all the values of the probe set according to 
## the langmuir absorption theory

collapse(SPIKE_INB[2])

## By comparing the matched value and the mismatches, you will be able to identify errors which 
## could have done while sampling the data, or if the error happens repeatedly this will show errors 
## which will have happened while sequencing old data.

Human Spike-in probe-set names

Description

This dataset contains the names of the Human probe-sets contained in the HGU dataset

Usage

data(SPIKE_INH)

Format

names of the human probe-sets contained in the HGU dataset

References

E. Carlon and T. Heim, Physica A 362, 433 (2006).

See Also

Ivsc, IvsDG, collapse, SPIKE_IN, hgu , SPIKE_INA, SPIKE_INB

Examples

## you can first check if the data matches the predicted hybridisation value according to the langmuir 
## value, from the intensity versus the concentration value
Ivsc(SPIKE_INH[3])

## you can then plot the value of the Intensity of the probe with the predicted value of the hybridisation
## according to the Delta G, value
IvsDG(SPIKE_INH[5],256)

## The collapse function will finally plot all the values of the probe set according to 
## the langmuir absorption theory

collapse(SPIKE_INH[2])

## By comparing the matched value and the mismatches, you will be able to identify errors which 
## could have done while sampling the data, or if the error happens repeatedly this will show errors 
## which will have happened while sequencing old data.