motif_tree: Generate 'ggplot2' motif trees with 'ggtree'.

In bjmt/universalmotif: Import, Modify, and Export Motifs with R

Generate ggplot2 motif trees with ggtree.

Description

For more powerful motif tree functions, see the motifStack package. The motif_tree() function compares motifs with compare_motifs() to create a distance matrix, which is used to generate a phylogeny. This can be plotted with ggtree::ggtree(). The purpose of this function is simply to combine the compare_motifs() and ggtree::ggtree() steps into one. For more control over tree creation, it is recommend to do these steps separately. See the "Motif comparisons and P-values" vignette for such a workthrough. This function requires the ape and ggtree packages to be installed separately.

Usage

motif_tree(motifs, layout = "circular", linecol = "family",
  labels = "none", tipsize = "none", legend = TRUE,
  branch.length = "none", db.scores, method = "EUCL", use.type = "PPM",
  min.overlap = 6, min.position.ic = 0, tryRC = TRUE, min.mean.ic = 0,
  relative_entropy = FALSE, progress = FALSE, nthreads = 1,
  score.strat = "a.mean", ...)

Arguments

motifs	list, dist See convert_motifs() for available formats. Alternatively, the resulting comparison matrix from compare_motifs() (run as.dist(results) beforehand; if the comparison was performed with a similarity metric, make sure to convert to distances first).
layout	character(1) One of c('rectangular', 'slanted', 'fan', 'circular', 'radial', 'equal_angle', 'daylight'). See ggtree::ggtree().
linecol	character(1) universalmotif slot to use to colour lines (e.g. 'family'). Not available for dist input (see examples for how to add it manually). See ggtree::ggtree().
labels	character(1) universalmotif slot to use to label tips (e.g. 'name'). For dist input, only 'name' is available. See ggtree::ggtree().
tipsize	character(1) universalmotif slot to use to control tip size (e.g. 'icscore'). Not available for dist input (see examples for how to add it manually). See ggtree::ggtree().
legend	logical(1) Show legend for line colour and tip size. See ggtree::ggtree().
branch.length	character(1) If 'none', draw a cladogram. See ggtree::ggtree().
db.scores	data.frame See compare_motifs().
method	character(1) One of PCC, EUCL, SW, KL, ALLR, BHAT, HELL, SEUCL, MAN, ALLR_LL, WEUCL, WPCC. See details.
use.type	character(1)c('PPM', 'ICM')⁠. The latter allows for taking into account the background frequencies (only if ⁠relative_entropy = TRUE'). See compare_motifs().
min.overlap	numeric(1) Minimum overlap required when aligning the motifs. Setting this to a number higher then the width of the motifs will not allow any overhangs. Can also be a number between 0 and 1, representing the minimum fraction that the motifs must overlap.
min.position.ic	numeric(1) Minimum information content required between individual alignment positions for it to be counted in the final alignment score. It is recommended to use this together with normalise.scores = TRUE, as this will help punish scores resulting from only a fraction of an alignment.
tryRC	logical(1) Try the reverse complement of the motifs as well, report the best score.
min.mean.ic	numeric(1) Minimum mean information content between the two motifs for an alignment to be scored. This helps prevent scoring alignments between low information content regions of two motifs. Note that this can result in some comparisons failing if no alignment passes the mean IC threshold. Use average_ic() to filter out low IC motifs to get around this if you want to avoid getting NAs in your output.
relative_entropy	logical(1) Change the ICM calculation affecting min.position.ic and min.mean.ic. See convert_type().
progress	logical(1) Show message regarding current step.
nthreads	numeric(1) Run compare_motifs() in parallel with nthreads threads. nthreads = 0 uses all available threads.
score.strat	character(1) How to handle column scores calculated from motif alignments. "sum": add up all scores. "a.mean": take the arithmetic mean. "g.mean": take the geometric mean. "median": take the median. "wa.mean", "wg.mean": weighted arithmetic/geometric mean. "fzt": Fisher Z-transform. Weights are the total information content shared between aligned columns.
...	ggtree params. See ggtree::ggtree().

Details

See compare_motifs() for more info on comparison parameters.

Value

ggplot object.

Author(s)

Benjamin Jean-Marie Tremblay, [e-mail]

References

Wickham H (2009). ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag New York. ISBN 978-0-387-98140-6, <URL: http://ggplot2.org>.

Yu G, Smith D, Zhu H, Guan Y, Lam TT (2017). “ggtree: an R package for visualization and annotation of phylogenetic trees with their covariates and other associated data.” Methods in Ecology and Evolution, 8, 28-36. doi: 10.1111/2041-210X.12628.

See Also

motifStack::motifStack(), compare_motifs(), ggtree::ggtree(), ggplot2::ggplot()

Examples

jaspar <- read_jaspar(system.file("extdata", "jaspar.txt",
                                  package = "universalmotif"))
if (requireNamespace("ggtree", quietly = TRUE)) {
jaspar.tree <- motif_tree(jaspar, linecol = "none", labels = "name",
                          layout = "rectangular")
}

## Not run: 
## When inputting a dist object, the linecol and tipsize options are
## not available. To add these manually:

library(MotifDb)
library(ggtree)
library(ggplot2)

motifs <- filter_motifs(MotifDb, organism = "Athaliana")[1:50]
comparison <- compare_motifs(motifs, method = "PCC", score.strat = "a.mean")
comparison <- as.dist(1 - comparison)
mot.names <- attr(comparison, "Labels")
tree <- motif_tree(comparison)

annotations <- data.frame(label = mot.names,
                          icscore = sapply(motifs, function(x) x["icscore"]),
                          family = sapply(motifs, function(x) x["family"]))

tree <- tree %<+% annotations +
          geom_tippoint(aes(size = icscore)) +
          aes(colour = family) +
          theme(legend.position = "right",
                legend.title = element_blank())

## End(Not run)

bjmt/universalmotif documentation built on March 18, 2024, 8:32 a.m.