Package 'DiscoRhythm'

Title: Interactive Workflow for Discovering Rhythmicity in Biological Data
Description: Set of functions for estimation of cyclical characteristics, such as period, phase, amplitude, and statistical significance in large temporal datasets. Supporting functions are available for quality control, dimensionality reduction, spectral analysis, and analysis of experimental replicates. Contains a R Shiny web interface to execute all workflow steps.
Authors: Matthew Carlucci [aut, cre], Algimantas Kriščiūnas [aut], Haohan Li [aut], Povilas Gibas [aut], Karolis Koncevičius [aut], Art Petronis [aut], Gabriel Oh [aut]
Maintainer: Matthew Carlucci <[email protected]>
License: GPL-3
Version: 1.23.0
Built: 2024-10-30 05:28:22 UTC
Source: https://github.com/bioc/DiscoRhythm

Help Index


Launch the DiscoRhythm Shiny Application

Description

This launches the web interface to DiscoRhythm containing all analysis tools. The vignette contains details on usage.

Usage

discoApp(ncores = 1, port = 3838, local = TRUE)

Arguments

ncores

numeric, number of cores to use for parallelized tasks. Currently, only used in oscillation detection function discoODAs.

port

numeric, port to run the shiny application on. Sets shiny.port option.

local

logical, set to FALSE for public server mode to reduce file size limits.

Value

Nothing is returned by this function.

Examples

## Not run: 
 discoApp()

## End(Not run)

Core DiscoRhythm Workflow

Description

Execute the DiscoRhythm workflow with one command to obtain the results of oscillation detection (discoODAs) and optionally generate an html report with data visualizations from an Rmarkdown template. See the DiscoRhythm vignette for more details on the analysis procedures.

Usage

discoBatch(
  indata,
  report = NULL,
  outdata = TRUE,
  ncores = 1,
  timeType = "circular",
  main_per = 24,
  cor_threshold = 3,
  cor_method = "pearson",
  cor_threshType = "sd",
  pca_threshold = 3,
  pca_scale = TRUE,
  pca_pcToCut = paste0("PC", seq_len(4)),
  aov_method = "None",
  aov_pcut = 0.05,
  aov_Fcut = 0,
  avg_method = "Median",
  osc_method = NULL,
  osc_period = 24
)

Arguments

indata

SummarizedExperiment or data.frame, see the vignette for the specific formats expected for each of these input types. discoParseMeta.

report

character, if !is.null(report) an html report with

outdata

logical, whether to return the final discoODAs (note if run with is.null(report) discoBatch will return nothing).

ncores

numeric, number of cores to use for parallelized tasks. Currently, only used in oscillation detection function discoODAs.

timeType

character, nature of the sample times provided (one of "circular" or "linear").

main_per

numeric, the length of the main hypothesized period (e.g. 24hr for circadian experiments). Used in discoPeriodDetection.

cor_threshold

numeric, threshold used in inter-sample correlation analysis for outlier detection. Either in units of correlation coefficient or standard deviations from the mean (see cor_threshType).

cor_method

character, which correlation method to use for outlier removal (see cor for more details).

cor_threshType

character, one of "sd" or "value" indicating whether cor_threshold should be set by absolute correlation coefficient or by standard deviations from the mean of all samples.

pca_threshold

numeric, the number of standard deviations to set as the threshold for outlier detection in PCA outlier removal.

pca_scale

logical, whether to scale the data prior to PCA.

pca_pcToCut

character, names of which PCs to use for outlier detection (e.g. "PC1","PC2" etc.).

aov_method

character, method to use for ANOVA. One of: "Equal Variance", "Welch", or "None".

aov_pcut

numeric, p-value cutoff used to select rows with statistically significant signal-to-noise.

aov_Fcut

numeric, F-statistic cutoff used to select rows with high signal-to-noise based on magnitude.

avg_method

character, method for averaging technical replicates. One of: "Median","Mean","Random", or "None".

osc_method

character, vector of oscillation detection algorithms to apply to the data. Methods that are detmined to be innappropraite for the experimental design (using the discoODAexclusionMatrix) will be ignored. If is.null(osc_method) all suitable methods will be executed.

osc_period

numeric, a fixed period to use for oscillation detection using all methods.

Value

returns the results of discoODAs

See Also

discoODAs, discoRepAnalysis, discoPeriodDetection, discoPCAoutliers, discoInterCorOurliers

Examples

indata <- discoGetSimu()

# Batch execute (on demo data) to generate a DiscoRhythm_report.html report.
# Returns the results of discoODAs
discoODAres <- discoBatch(indata,
report="DiscoRhythm_report.html",
osc_method="CS")

Import Data for DiscoRhythm Analysis

Description

Performs various checks and cleaning operations on the input data.

Usage

discoCheckInput(se, n_min_sample = 3)

Arguments

se

SummarizedExperiment, the main data object used by DiscoRhythm expected to contain se$ID, se$ReplicateID, se$Time sample metadata and non-null rownames. See the vignette for more details.

n_min_sample

numeric value specifying minimal number of samples needed to perform analysis.

Details

Rows containing NA's or all constant values are removed. If matrix values are character it will be attempted to convert them to numeric. If input is not a matrix it will be converted using as.matrix(). User will be warned if row IDs contain duplicate entries.

Value

SummarizedExperiment checked for errors and modified as needed

Examples

se <- discoGetSimu(TRUE)
se_clean <- discoCheckInput(se)

Summarize the experimental design

Description

Using sample times and biological sample Ids, constructs a summary table of the number of total samples at each timepoint and additionally summarizes the number of replicates for each biological sample.

Usage

discoDesignSummary(Metadata)

Arguments

Metadata

data.frame of sample data, usually generated by using discoParseMeta on the column names of the Maindata data.frame. If is.null(Metadata) and Maindata is provided as input, Metadata will be generated from Maindata.

Value

A table where the first row summarizes the number of datapoints for each timepoint and other cells indicate the number of technical replicates for a given biological sample.

See Also

discoParseMeta

Examples

# import example data
Metadata <- SummarizedExperiment::colData(discoGetSimu(TRUE))
# Summarize the experiment design
discoDesignSummary(Metadata)

Data formatting for DiscoRhythm

Description

Functions to import a data.frame (from the format expected by the web application discoApp()) as a SummarizedExperiment object or to export a SummarizedExperiment for use with the web application.

Usage

discoDFtoSE(Maindata, Metadata = NULL, shinySession = NULL)

discoSEtoDF(se)

Arguments

Maindata

data.frame with the first column containing row IDs and all subsequent columns containing experimental values. Columns should follow the expected naming format described in the vignette.

Metadata

data.frame of sample data, usually generated by using discoParseMeta on the column names of the Maindata data.frame. If is.null(Metadata) and Maindata is provided as input, Metadata will be generated from Maindata.

shinySession

shiny session object for use only by the DiscoRhythm shiny app discoApp() to update the axis labels using the time value prefix.

se

SummarizedExperiment, the main data object used by DiscoRhythm expected to contain se$ID, se$ReplicateID, se$Time sample metadata and non-null rownames. See the vignette for more details.

Value

discoDFtoSE returns a SummarizedExperiment object with colData containing sample metadata.

discoSEtoDF returns a DiscoRhythm format data.frame.

Examples

df <- discoGetSimu()
se <- discoDFtoSE(df)

df <- discoSEtoDF(se)

Read in the DiscoRhythm Simulated dataset

Description

A convenience function to get the simulated circadian transcriptomic system data file used in DiscoRhythm for various demonstrations and tests.

Usage

discoGetSimu(as_se = FALSE)

Arguments

as_se

logical, indicates if example data should be returned as a SummarizedExperiment or data.frame.

Value

The simulated demo dataset used in the DiscoRhythm web application as a data.frame or SummarizedExperiment.

Examples

indata <- discoGetSimu()

Algorithm Exclusion Matrix

Description

A small matrix indicating which algorithms should be excluded given certain experimental designs and data types.

Usage

discoODAexclusionMatrix

Format

An object of class matrix (inherits from array) with 4 rows and 7 columns.

Examples

# Code used to generate discoODAexclusionMatrix

itemNames <- c(
 "missing_value",
  "with_bio_replicate",
  "non_integer_interval",
  "uneven_interval",
  "circular_t",
  "invalidPeriod",
  "invalidJTKperiod"
)

# Creating requirements matrix, first assuming all methods are valid
# Then appying exclusion criteria of MetaCycle plus CS criteria
mat <- matrix(TRUE, nrow = 4, ncol = length(itemNames))
rownames(mat) <- c("CS", "JTK", "LS", "ARS")
colnames(mat) <- itemNames

# Exclusion criteria from MetaCycle v1.1, i.e. can algorithm handle XXX
mat[c("ARS", "JTK"), c("non_integer_interval", "uneven_interval")] <- FALSE
mat["ARS", "with_bio_replicate"] <- FALSE
mat["ARS", "missing_value"] <- FALSE
mat["JTK", "invalidJTKperiod"] <- FALSE

# Additional exclusion criteria
mat["ARS", "circular_t"] <- FALSE
mat[c("CS", "JTK", "ARS", "LS"), "invalidPeriod"] <- FALSE

discoODAexclusionMatrix <- mat

Mapping Identifiers to Full Names

Description

A small named vector mapping oscillation detection algorithm names to a convenient identifier.

Usage

discoODAid2name

Format

A named vector, length 4

names(discoODAid2name)

Identifier

as.vector(discoODAid2name)

Full names


Execute Oscillation Detection Using DiscoRhythm

Description

Runs specified oscillation detection algorithms (ODAs) sequentially to obtain oscillation characteristics for each row of the input data.

Usage

discoGetODAs(se, method = NULL, period, circular_t = FALSE)

discoODAs(
  se,
  period = 24,
  method = c("CS", "JTK", "LS", "ARS"),
  circular_t = FALSE,
  ncores = 1
)

Arguments

se

SummarizedExperiment, the main data object used by DiscoRhythm expected to contain se$ID, se$ReplicateID, se$Time sample metadata and non-null rownames. See the vignette for more details.

method

character, short names of ODAs to use. If length>1 all input method names will be evaluated.

period

numeric, the hypothesized period to test for.

circular_t

logical, is time circular on some base-cycle (ex. time of day). See the DiscoRhythm vignette for details.

ncores

numeric, number of cores to parallelize with (applicable to JTK, ARSER and LS only). If 1, will execute in serial.

Details

There are currently 4 available algorithms for rhythm detection:

  • CS = Cosinor (Cornelissen,G. 2014): a.k.a “Harmonic Regression” fits a sinusoid with a free phase parameter.

  • LS = Lomb-Scargle (Glynn, 2006): an approach using spectral power density.

  • ARS = ARSER (Yang, 2010): removes linear trends and performs the Cosinor test.

  • JTK = JTK Cycle (Hughes, 2010): non-parametric test of rhythmicity robust to outliers.

LS, ARS, and JTK results come directly from MetaCycle meta2d() output using the specified fixed period. ARSmle is set to "nomle" and no method integration is used (see meta2d documentation for details).

CS is implemented directly in DiscoRhythm's lmCSmat() as the single-component cosinor described in Cornelissen,G. (2014).

All q-values are calculated by performing p.adjust() on the resulting p-values with method="fdr".

Technical replicates are expected to be merged (likely by discoRepAnalysis) prior to usage of discoODAs.

The discoGetODAs function is called by discoODAs to determine if the selected methods may be used. If any methods are not valid, a warning will be thrown and only valid methods will be computed. discoGetODAs is not typically used directly, however, it may be called by the user to determine if the provided SummarizedExperiment is suitable for use with the specified methods.

Value

A named list of results where each element is a data.frame for the corresponding method with rownames corresponding to the feature identifiers and columns containing estimates for:

  • acrophase

  • amplitude

  • p-value

  • q-value

Additional columns relevant to each method will be present.

References

Yang R. and Su Z. (2010). Analyzing circadian expression data by harmonic regression based on autoregressive spectral estimation. Bioinformatics, 26(12), i168–i174.

Hughes M. E., Hogenesch J. B. and Kornacker K. (2010). JTK_CYCLE: an efficient nonparametric algorithm for detecting rhythmic components in genome-scale data sets. Journal of Biological Rhythms, 25(5), 372–380.

Glynn E. F., Chen J. and Mushegian A. R. (2006). Detecting periodic patterns in unevenly spaced gene expression time series using Lomb-Scargle periodograms. Bioinformatics, 22(3), 310–316.

Cornelissen,G. (2014) Cosinor-based rhythmometry. Theor. Biol. Med. Model., 11, 16.

See Also

lmCSmat meta2d

Examples

# Return valid ODAs for example dataset
discoGetODAs(discoGetSimu(as_se=TRUE),period=24)

# Import the simulated example dataset
se <- discoCheckInput(discoGetSimu(TRUE))

# Use discoRepAnalysis to average technical replicates
se_merged <- discoRepAnalysis(se,aov_pcut=1)$se

# Execute the Cosinor and JTK methods with a 24hr period
discoODAres <- discoODAs(se_merged,method=c("CS","JTK"))

# Get the index of rhythmic features detected by both methods at qvalue<0.05
idx <- which(discoODAres$CS$qvalue<0.05 & discoODAres$JTK$qvalue<0.05)

# Get the identifiers for common rhythmic features
rownames(se_merged)[idx]

Generate Experiment Metadata

Description

Parses the sample metadata from a vector of sample names (often column names of a Maindata format data.frame).

Usage

discoParseMeta(samplenames, shinySession = NULL)

Arguments

samplenames

character, a list of sample names following the DiscoRhythm naming convention (<prefix><Time>_<UniqueID>_<ReplicateID>).

shinySession

shiny session object for use only by the DiscoRhythm shiny app discoApp() to update the axis labels using the time value prefix.

Details

The regular expression used to obtain metadata is "^([[:alpha:]]*)(\-?[0-9]+[\.]?[0-9]*)\_? ([[:alnum:]\.]*)\_?([[:alnum:]\.]*)$"

Where each () will be used to construct the final metadata data.frame

Value

a data.frame containing 3 columns of metadata. ID = unique sample identity. Time = sample colleciton time. ReplicateID = Identifier where Time + ReplicateID indicates a biological sample ID.

Examples

discoParseMeta(c("CT24_AD_1","CT24_AS_1","CT24_AE_2","CT24_AW_2",
"CT26_AB_1","CT26_AC_1","CT26_BB_2","CT26_BC_2"))

Perform PCA

Description

Calculates PCA results from prcomp with error handling and outputs suitable for the DiscoRhythm workflow.

Usage

discoPCA(se, scale = TRUE, npcs = 10)

Arguments

se

SummarizedExperiment, the main data object used by DiscoRhythm expected to contain se$ID, se$ReplicateID, se$Time sample metadata and non-null rownames. See the vignette for more details.

scale

logical, whether or not to scale the data prior to PCA, see prcomp for more details.

npcs

numeric, maximum number of principal components to return.

Value

output from prcomp with an added table summary

Examples

se <- discoGetSimu(TRUE)
pca <- discoPCA(se)

Detect dataset-wide fits to multiple periodicities

Description

Detect dataset-wide fits to multiple periodicities

Usage

discoPeriodDetection(
  se,
  timeType = c("linear", "circular"),
  main_per = 24,
  test_periods = NULL
)

Arguments

se

SummarizedExperiment, the main data object used by DiscoRhythm expected to contain se$ID, se$ReplicateID, se$Time sample metadata and non-null rownames. See the vignette for more details.

timeType

character, time is either reported as "linear" or "circular" on some base-cycle (ex. time of day). This determines the periods that will be tested for.

main_per

numeric, if timeType=="circular" main_per indicates the period of the base-cycle where sampling times are derived.

test_periods

numeric, a vector of the periods to test. if timeType=="linear" and length(test_periods)==2 it will be assumed to be a range of periods to test over.

Value

A data.frame of Rsquared values for each period, for each row of Maindata.

Examples

se <- discoGetSimu(TRUE)

# Detect periods
rsqs <- discoPeriodDetection(se)

Quality Control for DiscoRhythm

Description

Functions for executing outlier detection and row filtering procedures prior to rhythmicity analysis.

Usage

discoPCAoutliers(se, threshold = 3, scale = TRUE, pcToCut = seq_len(4))

discoInterCorOutliers(
  se,
  cor_method = c("pearson", "kendall", "spearman"),
  threshold = 3,
  thresh_type = c("sd", "value")
)

discoRepAnalysis(
  se,
  aov_method = c("Equal Variance", "Welch", "None"),
  aov_pcut = 0.05,
  aov_Fcut = 0,
  avg_method = c("Median", "Mean", "Random", "None")
)

Arguments

se

SummarizedExperiment, the main data object used by DiscoRhythm expected to contain se$ID, se$ReplicateID, se$Time sample metadata and non-null rownames. See the vignette for more details.

threshold

numeric, a threshold determining which samples are outliers (for discoInterCorOutliers, in units of thresh_type, for discoPCAoutliers in units of standard deviations).

scale

logical, whether or not to scale the data prior to PCA, see prcomp for more details.

pcToCut

numeric, which PCs to use for outlier detection. It is recomended to select the first X PCs based on which PCs explain a significant amount of variance in the data.

cor_method

character, method of pairwise correlation (see cor's "method" argument for all options).

thresh_type

character indicating threshold type (either standard deviations below the mean, or an absolution correlation value). One of: "sd" or "value".

aov_method

character, method to use for ANOVA. One of: "Equal Variance", "Welch", or "None".

aov_pcut

numeric, p-value cutoff used to select rows with statistically significant signal-to-noise.

aov_Fcut

numeric, F-statistic cutoff used to select rows with high signal-to-noise based on magnitude.

avg_method

character, method for averaging technical replicates. One of: "Median","Mean","Random", or "None".

Value

list containing PCA results and the detected outliers

A list of 3 objects: 1) outliers - named logical indicating if the sample is an outlier 2) meanCor - mean of all pairwise correlations for a given sample 3) corMat - Matrix of all pairwise correlation values

Examples

se <- discoGetSimu(TRUE)
PCAres <- discoPCAoutliers(se)

CorRes <- discoInterCorOutliers(se)

ANOVAres <- discoRepAnalysis(se)