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Paul Shannon
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@paul-shannon-578
Last seen 10.2 years ago
Hi Patrick,
Thanks very much for these additions. After a couple of weeks
distraction working on other things, I am ready to try them out.
What is the standard approach -- to switch entirely over to R-devel
and the devel version of bioc? Are they likely to be plenty stable
for day-to-day use?
Or would I be wise to maintain a release installation as my default,
and only venture in to the devel installation cautiously, when I need
to use recent additions like those described below?
Thanks,
- Paul
On Jan 19, 2010, at 3:46 PM, Patrick Aboyoun wrote:
> Paul,
> The issue was that the code was depended on using R-devel as well as
the latest versions of BioC packages IRanges, Biostrings, and
BSgenome.
>
> Rather than trying to retrofit something into R 2.10 and BioC 2.5, I
went ahead and added a new vmatchPDict method for BSgenome objects
into
> BioC 2.6 for use with R-devel. I just checked the code in so it wont
be available from bioconductor.org until Thursday morning at the
earliest. If you want it earlier, you will need to get the latest
versions of IRanges, Biostrings, and BSgenome from the trunk of
Bioconductor's software svn. Below is an example of this new
functionality. I am trying to grow the use of RangedData objects as
containers for match output and am looking for any feedback on its
usability. In particular, I am looking for useful methods that are
missing from the packages referenced above so I can fill in the gaps.
>
>
> > suppressMessages(library(BSgenome))
> > library(BSgenome.Celegans.UCSC.ce2)
> > data(HNF4alpha) # a DNAStringSet object
> > vmatchPDict(HNF4alpha[1:10], Celegans)
> RangedData with 14 rows and 2 value columns across 7 spaces
> space ranges | strand index
> <character> <iranges> | <rle> <rle>
> 1 chrI [10714238, 10714250] | + 1
> 2 chrI [10242063, 10242075] | - 1
> 3 chrI [ 995608, 995620] | - 3
> 4 chrIII [ 360758, 360770] | + 1
> 5 chrIII [ 9996856, 9996868] | - 1
> 6 chrIV [16177061, 16177073] | + 3
> 7 chrIV [17014321, 17014333] | - 4
> 8 chrIV [ 6364368, 6364380] | - 10
> 9 chrV [11914362, 11914374] | + 1
> 10 chrV [19656881, 19656893] | + 2
> ...
> <4 more rows>
> > sessionInfo()
> R version 2.11.0 Under development (unstable) (2010-01-18 r50995)
> i386-apple-darwin9.8.0
>
> locale:
> [1] en_US.UTF-8/en_US.UTF-8/C/C/en_US.UTF-8/en_US.UTF-8
>
> attached base packages:
> [1] stats graphics grDevices utils datasets methods base
> other attached packages:
> [1] BSgenome.Celegans.UCSC.ce2_1.3.16 BSgenome_1.15.4
[3] Biostrings_2.15.18 IRanges_1.5.29
> loaded via a namespace (and not attached):
> [1] Biobase_2.7.3 tools_2.11.0
>
>
>
> Patrick
>
>
>
> Paul Shannon wrote:
>> Hi Patrick,
>>
>> Thanks very much!
>> Running your code just now, I get this:
>>
>> Error in function (classes, fdef, mtable) :
>> unable to find an inherited method for function "dups", for
signature "DNAStringSet"
>>
>> traceback () & sessionInfo pasted in below. Is dups perhaps defined
in the devel version of Biostrings?
>>
>> - Paul
>>
>>
>>
>>> traceback ()
>>>
>> 13: stop("unable to find an inherited method for function \"", fdef
at generic,
>> "\", for signature ", cnames)
>> 12: function (classes, fdef, mtable)
>> {
>> methods <- .findInheritedMethods(classes, fdef, mtable)
>> if (length(methods) == 1L)
>> return(methods[[1L]])
>> else if (length(methods) == 0L) {
>> cnames <- paste("\"", sapply(classes, as.character),
>> "\"", sep = "", collapse = ", ")
>> stop("unable to find an inherited method for function
\"",
>> fdef at generic, "\", for signature ", cnames)
>> }
>> else stop("Internal error in finding inherited methods;
didn't return a unique method")
>> }(list("DNAStringSet"), function (x)
>> standardGeneric("dups"), <environment>)
>> 11: dups(pdict)
>> 10: .matchPDict(pdict, subject, algorithm, max.mismatch,
min.mismatch,
>> fixed, verbose) at go.R#27
>> 9: matchPDict(pdict = posPDict, subject = chr) at go.R#27
>> 8: matchPDict(pdict = posPDict, subject = chr) at go.R#27
>> 7: BSParams at FUN(seq, ...)
>> 6: FUN(c("chrI", "chrII", "chrIII", "chrIV", "chrV", "chrX", "chrM"
>> )[[1L]], ...)
>> 5: lapply(X, FUN, ...)
>> 4: sapply(seqnames, processSeqname, ...)
>> 3: sapply(seqnames, processSeqname, ...)
>> 2: bsapply(bsParams, strings = HNF4alpha) at go.R#14
>> 1: run(0)
>>
>>> sessionInfo ()
>>>
>> R version 2.10.0 (2009-10-26)
>> x86_64-apple-darwin9.8.0
>>
>> locale:
>> [1] en_US.utf-8/en_US.utf-8/C/C/en_US.utf-8/en_US.utf-8
>>
>> attached base packages:
>> [1] stats graphics grDevices utils datasets methods
base
>>
>> other attached packages:
>> [1] BSgenome.Celegans.UCSC.ce2_1.3.16 BSgenome_1.14.2
Biostrings_2.14.8 IRanges_1.4.8
>>
>> loaded via a namespace (and not attached):
>> [1] Biobase_2.6.0 tools_2.10.0
>>
>>
>> On Jan 15, 2010, at 3:00 PM, Patrick Aboyoun wrote:
>>
>>
>>> Paul,
>>> I have made a first attempt at solving the first part of your
problem (mapping the motifs to the genome) and plan on making this
easier to perform by adding a vmatchPDict method to the BSgenome
package in BioC 2.6. For now, here is some code that creates a
RangedData object identifying the locations on the genome where the
motifs match. You can then use findOverlaps against a RangedData
object that contains the annotations that are of interest to you.
Feedback is welcome. - Patrick
>>>
>>>
>>> ## load the base libraries
>>> library(Biostrings)
>>> library(BSgenome)
>>>
>>> ## load the genome
>>> library(BSgenome.Celegans.UCSC.ce2)
>>>
>>> ## create the motifs
>>> data(HNF4alpha)
>>>
>>> ## -------------------------------------------------------------
>>> ## method for finding motif locations on genome
>>> ## the motifId column is an element identifier
>>> ## that relates back to the original motif set
>>> matchFUN <- function(strings, chr) {
>>> posPDict <- strings
>>> negPDict <- reverseComplement(strings)
>>> posMatches <- matchPDict(pdict = posPDict, subject = chr)
>>> posCounts <- elementLengths(posMatches)
>>> negMatches <- matchPDict(pdict = negPDict, subject = chr)
>>> negCounts <- elementLengths(negMatches)
>>> strand <-
>>> strand(rep(c("+", "-"), c(sum(posCounts), sum(negCounts))))
>>> motifId <-
>>> c(rep(seq_len(length(posMatches)), posCounts),
>>> rep(seq_len(length(negMatches)), negCounts))
RangedData(c(unlist(posMatches), unlist(negMatches)),
>>> strand = strand, motifId = motifId)
>>> }
>>> bsParams <-
>>> new("BSParams", X = Celegans, FUN = matchFUN, simplify = TRUE)
>>> matches <- bsapply(bsParams, strings = HNF4alpha)
>>> nms <- names(matches)
>>> matches <- do.call(c, unname(matches))
>>> names(matches) <- nms
>>> ## -------------------------------------------------------------
>>>
>>>
>>>> matches
>>>>
>>> RangedData with 183 rows and 2 value columns across 7 spaces
>>> space ranges | strand motifId
>>> <character> <iranges> | <factor> <integer>
>>> 1 chrI [10714238, 10714250] | + 1
>>> 2 chrI [ 1746247, 1746259] | + 33
>>> 3 chrI [11509260, 11509272] | + 39
>>> 4 chrI [ 5249651, 5249663] | + 48
>>> 5 chrI [ 5442409, 5442421] | + 64
>>> 6 chrI [ 7949495, 7949507] | + 64
>>> 7 chrI [ 2788492, 2788504] | + 71
>>> 8 chrI [ 3853105, 3853117] | + 71
>>> 9 chrI [ 6952606, 6952618] | + 71
>>> 10 chrI [10242063, 10242075] | - 1
>>> ...
>>> <173 more rows>
>>>
>>>
>>>
>>> Paul Shannon wrote:
>>>
>>>> Can I get advice from on good ways to find genes -- perhaps with
a high false-positive rate -- whose promoters contain known DNA
binding motifs?
>>>>
>>>> Hu et al, "Profiling the Human Protein-DNA Interactome Reveals
ERK2 as a Transcriptional Repressor of Interferon Signaling"
identifies
>>>>
>>>> 17,718 PDIs [protein-DNA interactions] between 460 DNA motifs
predicted to regulate transcription and 4,191 human proteins of
various functional classes.
>>>>
>>>> I wish to take those 460 motifs -- many of them only 7 bases long
-- and find the genes whose transcription they control.
>>>>
>>>> I suspect the answer lies in some artful use of Biostrings,
BSgenome (which together provide efficient genome search), along with
annotation to find the transcription start site of known genes. But
before I start, I think it prudent to get the advice of those who may
know more than me.
>>>>
>>>> Thanks!
>>>>
>>>> - Paul
>>>> _______________________________________________
>>>> Bioconductor mailing list
>>>> Bioconductor at stat.math.ethz.ch
>>>> https://stat.ethz.ch/mailman/listinfo/bioconductor
>>>> Search the archives:
http://news.gmane.org/gmane.science.biology.informatics.conductor
>>>>
>>
>>
>