DTA (version 2.18.0)

DTA.estimate: Estimation of synthesis and decay rates

Description

DTA.estimate uses an experiment, given by a phenotype matrix, data matrix and the number of uridines for each gene to estimate synthesis and decay rate of the genes.

Usage

DTA.estimate(phenomat = NULL,datamat = NULL,tnumber = NULL,reliable = NULL,ccl = NULL,mRNAs = NULL,mediancenter = TRUE,usefractions = "LandT",LtoTratio = NULL,ratiomethod = "tls",largest = 5,weighted = TRUE,relevant = NULL,upper = 700,lower = 500,error = TRUE,samplesize = 1000,confidence.range = c(0.025,0.975),bicor = TRUE,check = TRUE,condition = "",save.plots = FALSE,resolution = 1,notinR = FALSE,RStudio = FALSE,folder = NULL,fileformat = "jpeg",totaloverwt = 1,simulation = FALSE,sim.object = NULL)

Arguments

phenomat

A phenotype matrix, containing the design of the experiment as produced by DTA.phenomat. Columns are name, fraction (U=unlabebeld, L=labeled, T=total), time and nr (=replicate number). Rows represent individual experiments.

datamat

A matrix, containing the measurements from U, L and T, according to the design given in phenomat. Matrix should only contain the rows of phenomat as columns.

tnumber

Integer vector, containing the numbers of uridine residues for each transcript. Elements should have the rownames of datamat.

ccl

The cell cycle length of the cells (optional). Is not modeled, if not set.

mRNAs

Estimated number of mRNAs in a cell (optional).

reliable

Vector of 'reliable' genes, which are used for parameter estimation.

mediancenter

Should the quotient Labeled/Total resp. Unlabeled/Total be rescaled to a common median over it's replicates before building the genewise median.

usefractions

From which fractions should the decay rate be calculated: "LandT", "UandT" or "both".

LtoTratio

Coefficient to rescale Labeled/Total. Is estimated from the data, if not specified. See ratiomethod. Altering this parameter leads to a altered median half-life. For details, see supplemental material of Sun et al. (see references).

ratiomethod

Choose the regression method to be used, possible methods are: "tls", "bias" and "lm". For details, see supplemental material of Sun et al. (see references). Method to estimate the parameter LtoTratio, which determines the median half-life of the sample.

largest

Percentage of largest residues from the first regression not to be used in the second regression step. For details, see supplemental material of Sun et al. (see references).

weighted

Should the regression be weighted with 1/(Total^2 + median(Total))?

relevant

Choose the arrays to be used for halflives calculation, vector due to nr (=replicate number) in phenomat. If not set, all arrays are used.

check

If check = TRUE, control messages and plots will be generated.

error

If TRUE, the measurement error is assessed by means of an error model and resampling to gain confidence regions.

samplesize

Error model samplesize for resampling.

confidence.range

Confidence region for error model as quantiles. Interval should be between 0 and 1.

bicor

Should the labeling bias be corrected?

condition

String, to be added to the plotnames if saved.

upper

Upper bound for labeling bias estimation. For details, see supplemental material of Sun et al. (see references).

lower

Lower bound for labeling bias estimation. For details, see supplemental material of Sun et al. (see references).

save.plots

If save.plots = TRUE, control plots will be saved. Please check folder writability.

resolution

Resolution scaling factor for plotting. (Scaled with 72dpi.)

notinR

If TRUE, plots are not plotted in R.

RStudio

For RStudio users. Suppresses the opening of a new device, as RStudio allows only one.

folder

Path to the folder, where to save the plots. Needs to be writable.

fileformat

Fileformat for plots to be saved. See plotit function (LSD package). Save the plot as "jpeg", "png", "bmp", "tiff", "ps" or "pdf".

totaloverwt

Only needed when mRNAs is set. Should give the factor by which the total mRNA of the condition outreaches that of the reference (comparative DTA data).

simulation

True, if data was generated by DTA.generate.

sim.object

Simulation object created by DTA.generate.

Value

DTA.estimate returns a list, where each entry contains the estimation results for all replicates of one labeling time. Each result contains the following entries

triples

Mapping of each fraction and experiment to its corresponding column in the data matrix.

plabel

The labeling efficiency. For details, see supplemental material of Sun et al. (see references).

LtoTratio

Estimated ratio of labeled to total fraction.

UtoTratio

Estimated ratio of unlabeled to total fraction.

LtoUratio

Estimated ratio of labeled to unlabeled fraction.

correcteddatamat

Labeling bias corrected data matrix.

drmat

Decay rates for each replicate. The last column gives the median decay rates.

dr

Median decay rates. The last column of drmat.

dr.confidence

Confidence regions of decay rates.

hlmat

Half-lives for each replicate. The last column gives the median half-lifes.

hl

Median half-lives. The last column of hlmat.

hl.confidence

Confidence regions of half-lives.

TEmat

Total expression for each replicate. The last column gives the median total expression values.

TE

Median total expression values. The last column of TEmat.

TE.confidence

Confidence regions of total expression values.

LEmat

Labeled expression for each replicate. The last column gives the median labeled expression values.

LE

Median labeled expression values. The last column of LEmat.

LE.confidence

Confidence regions of labeled expression values.

UEmat

Unlabeled expression for each replicate. The last column gives the median unlabeled expression values. (Only if unlabeled values exist in the experiment)

UE

Median unlabeled expression values. The last column of UEmat. (Only if unlabeled values exist in the experiment)

UE.confidence

Confidence regions of unlabeled expression values.

srmat

Synthesis rates for each replicate. The last column gives the median synthesis rates.

sr

Median synthesis rates. The last column of srmat.

sr.confidence

Confidence regions of synthesis rates.

LtoTmat

Labeled to total ratio for each replicate. The last column gives the median labeled to total ratios.

LtoT

Median labeled to total ratios. The last column of LtoTmat.

LtoT.confidence

Confidence regions of labeled to total ratios.

UtoTmat

Unlabeled to total ratio for each replicate. The last column gives the median unlabeled to total ratios.

UtoT

Median unlabeled to total ratios. The last column of UtoTmat.

UtoT.confidence

Confidence regions of unlabeled to total ratios.

Rsrmat

Rescaled synthesis rates for each replicate, if parameter mRNAs is specified. The last column gives the median synthesis rates.

Rsr

Rescaled median synthesis rates. The last column of Rsrmat.

globaldrmat

Decay rate for each replicate. Reciprocally weighted by the total expression. Last element contains (weighted) median decay rate.

globaldr

(Weighted) median decay rate.

References

C. Miller, B. Schwalb, K. Maier, D. Schulz, S. Duemcke, B. Zacher, A. Mayer, J. Sydow, L. Marcinowski, L. Doelken, D. E. Martin, A. Tresch, and P. Cramer. Dynamic transcriptome analysis measures rates of mRNA synthesis and decay in yeast. Mol Syst Biol, 7:458, 2011. M. Sun, B. Schwalb, D. Schulz, N. Pirkl, L. Lariviere, K. Maier, A. Tresch, P. Cramer. Mutual feedback between mRNA synthesis and degradation buffers transcript levels in a eukaryote. Under review. B. Schwalb, B. Zacher, S. Duemcke, D. Martin, P. Cramer, A. Tresch. Measurement of genome-wide RNA synthesis and decay rates with Dynamic Transcriptome Analysis (DTA/cDTA). Bioinformatics.

See Also

heatscatter, plotit, tls

Examples

dataPath = system.file("data", package="DTA")
load(file.path(dataPath, "Miller2011.RData"))

### for control plots set 'check = TRUE' ###

res = DTA.estimate(Sc.phenomat,Sc.datamat,Sc.tnumber,ccl = 150,mRNAs = 60000,reliable = Sc.reliable,check = FALSE)