#' @title MSA Reliability Assessment with GUIDANCE
#' @name guidance
#' @description Calculate MSA reliability scores with GUIDANCE (Penn et al. 2010).
#' @param sequences An object of class \code{\link{DNAbin}} or \code{\link{AAbin}} containing unaligned sequences of DNA or amino acids.
#' @param bootstrap An integer giving the number of alternative MSAs to be computed.
#' @param method A character string containing further arguments passed to MAFFT; default is \code{"auto"}.
#' @param msa.exec A character string giving the path to the executable of the
#' alignment program (e.g. \code{/usr/local/bin/mafft}); possible programs are
#' \code{MAFFT}, \code{MUSCLE}, \code{ClustalW}, \code{ClustalO} or \code{PRANK}
#' For details see \code{\link{clustal}}, \code{\link{mafft}}, \code{\link{prank}}
#' @param ncore An integer specifying the number of cores; default = 1 (i.e. serial execution); \code{"auto"} can be used for automated usage of all detected cores.
#' @param zip.file A character string giving the dir of zip-compressed file to be produced, which contains the alternative MSAs. If left empty (default), the alternative MSA will not be stored and cannot be assessed by the user.
#' @return An object of class \code{\linkS4class{guidanceDNA}} or \code{\linkS4class{guidanceAA}}.
#' @details Calculates column confidence (and other scores) by comparing
#' alternative MSAs generated by alternative guide trees derived from
#' bootstrapped MSAs (Felsenstein 1985). The basic comparison between the bootstrapped MSAs
#' and a reference MSA is if column residue pairs are identically aligned in
#' all alternative MSAs compared with the base MSA (see \code{msa_set_score}).
#' @details For an example workflow see Vignette
#' @references Felsenstein, J. 1985. Confidence limits on phylogenies: an
#' approach using the bootstrap. \emph{Evolution} \strong{39}:783--791.
#' @references Penn et al. 2010. An
#' alignment confidence score capturing robustness to guide tree uncertainty.
#' \emph{Molecular Biology and Evolution} \strong{27}:1759--1767.
#' @seealso \code{\link{msa_set_score}}, \code{\link{guidance2}}, \code{\link{HoT}}
#' @import ips
#' @importFrom doSNOW registerDoSNOW
#' @import foreach
#' @importFrom parallel detectCores makeCluster
#' @import pbmcapply
#' @import plyr
#' @importFrom phangorn as.phyDat dist.ml
#' @examples
#' \dontrun{
#' # run GUIDANCE on example data using MAFFT
#' fpath <- system.file("extdata", "BB30015.fasta", package="rGUIDANCE") # random example from BALiBASE
#' fas <- ape::read.FASTA(fpath)
#' g <- guidance(sequences = fas, msa.exec= "/usr/local/bin/mafft")
#' scores <- scores(g, score = "column")
#' plot(scores$column$score, xlab = "Site",
#' ylab = "Column score",
#' main = "GUIDANCE", type = "l")
#' }
#'
#' @author Franz-Sebastian Krah
#'
#' @export
guidance <- function(sequences,
bootstrap = 100,
method = "auto",
msa.exec = "/usr/local/bin/mafft",
ncore = 1,
zip.file){
##############################################
## SOME CHECKS
##############################################
if (!inherits(sequences, c("DNAbin", "AAbin")))
stop("sequences not of class DNAbin or AAbin (ape)")
nseq <- ifelse(is.matrix(sequences), nrow(sequences), length(sequences))
if (nseq < 8)
warning("GUIDANCE is not suitable for alignments of very few sequences.\n
As a rule of thumb, use guidance2 or HoT for < 8 sequences")
if (nseq > 199)
warning("alignments with more than 200 sequences may run into computional problems")
## look up MSA program specified
msa.program <- str_extract(msa.exec, "mafft|muscle|clustalo|clustalw|prank")
if (!msa.program %in% c("mafft", "muscle", "clustalw", "lustalo", "prank"))
stop("Currently only MAFFT, MUSCLE, ClustalW or ClustalO")
## Check for MSA program
out <- system(paste(msa.exec, "--v"), ignore.stdout = TRUE, ignore.stderr = TRUE)
if (out == 127)
stop("please provide msa.exec path or install MSA program in root \n
i.e. in Unix: '/usr/local/bin/mafft'")
## generate some parameters if not specified
## -----------------------------------------
## number of cores
if (ncore == "auto"){
ncore <- detectCores(all.tests = FALSE, logical = TRUE)
}
##############################################
## PART I
##############################################
## BASE and ALTERNATIVE MSAs
##############################################
## Make base alignment
## -------------------
cat("Generating the base alignment \n")
if (msa.program == "mafft") {
base_msa <- mafft(x = sequences,
exec = msa.exec, method = method,
thread = -1)
}
if (msa.program == "clustalo") {
base_msa <- clustalomega(x = sequences,
exec = msa.exec,
MoreArgs = "")
}
if (msa.program == "clustalw") {
base_msa <- clustal(x = sequences,
exec = msa.exec,
pw.gapopen = 10, pw.gapext = 0.1,
gapopen = 10, gapext = 0.2,
MoreArgs = "")
}
if (msa.program == "muscle") {
base_msa <- muscle(x = sequences,
exec = msa.exec,
MoreArgs = "")
}
if (msa.program == "prank") {
base_msa <- prank(x = sequences,
path = msa.exec,
gaprate = 0.025,
gapext = 0.75)
}
## Compute NJ guide trees
## ----------------------
cat("Generating NJ guide trees\n")
pb <- txtProgressBar(max = bootstrap, style = 3)
progress <- function(n) setTxtProgressBar(pb, n)
opts <- list(progress = progress)
cl <- makeCluster(ncore)
registerDoSNOW(cl)
nj_guidetrees <- foreach(i = 1:bootstrap,
.options.snow = opts,
.packages = "phangorn",
.export = 'msaBP_nj_tree') %dopar% {
msaBP_nj_tree(msa = base_msa, outgroup = "auto")
}
stopCluster(cl)
close(pb)
## Alignment of MSA BP times with new NJ guide trees
## -------------------------------------------------
cat("Alignment of sequences using NJ guide trees\n")
## Construct alignment function
## ----------------------------
## loop
progress <- function(n) setTxtProgressBar(pb, n)
opts <- list(progress = progress)
cl <- makeCluster(ncore)
registerDoSNOW(cl)
if (msa.program == "mafft") {
alt_msa <- foreach(i = 1:bootstrap,
.options.snow = opts) %dopar% {
mafft(x = sequences, gt = nj_guidetrees[[i]],
exec = msa.exec, method = method,
maxiterate = 0, op = 1.53, ep = 0,
thread = 1)
}
}
if (msa.program == "clustalo") {
alt_msa <- foreach(i = 1:bootstrap,
.options.snow = opts,
.export = c("sequences", "nj_guidetrees", "msa.exec")) %dopar% {
clustalomega(x = sequences, guide.tree = nj_guidetrees[[i]],
exec = msa.exec, MoreArgs = "")
}
}
if (msa.program == "clustalw") {
alt_msa <- foreach(i = 1:bootstrap,
.options.snow = opts,
.export = c("sequences", "nj_guidetrees", "msa.exec")) %dopar% {
clustal(x = sequences, guide.tree = nj_guidetrees[[i]],
exec = msa.exec,
pw.gapopen = 10, pw.gapext = 0.1,
gapopen = 10, gapext = 0.2,
MoreArgs = "")
}
}
if (msa.program == "muscle") {
alt_msa <- foreach(i = 1:bootstrap,
.options.snow = opts,
.export = c("sequences", "nj_guidetrees", "msa.exec")) %dopar% {
muscle(x = sequences, guide.tree = nj_guidetrees[[i]],
exec = msa.exec, MoreArgs = "")
}
}
if (msa.program == "prank") {
alt_msa <- foreach(i = 1:bootstrap,
.options.snow = opts,
.export = c("sequences", "nj_guidetrees", "msa.exec")) %dopar% {
prank(x = sequences, guidetree = nj_guidetrees[[i]],
path = msa.exec,
gaprate = 0.025,
gapext = 0.75)
}
}
stopCluster(cl)
close(pb)
## Delete leftover files from MAFFT
file.remove(list.files(pattern = "tree.mafft", full.names = TRUE))
##############################################
## PART II
##############################################
## Computation of GUIDANCE scores
##############################################
cat("\nCalculating GUIDANCE scores \n")
## Run msa_set_score
score <- msa_set_score(ref = base_msa,
alt = alt_msa)
## Store alternative MSAs in a zip file (optional)
## -----------------------------------------------
if (!missing(zip.file)){
for (i in seq_along(alt_msa)){
write.FASTA(alt_msa[[i]], file =paste0(zip.file, "alt_msa_", i, ".fas"))
}
files <- list.files(zip.file, full.names = TRUE)
files <- files[grep("alt_msa", files)]
zip(zipfile = paste0(zip.file, "guidance_alt_msas_", Sys.Date(), ".zip"), files = files)
file.remove(files)
}
## Delete temporary files
# this deletion approach has proven best to delete everything
files <- list.files(tempdir(), full.names = TRUE)
files <- files[-grep("rs-graphics", files)]
unlink(files, force = TRUE, recursive = TRUE)
## Return guidance class
## -------------------------
if (inherits(sequences, "AAbin")){
guidanceAA(base_msa, score, "guidance", msa.program)
} else {
guidanceDNA(base_msa, score, "guidance", msa.program)
}
}
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