I downloaded RepeatMasker from the Table Browser:
http://genome.ucsc.edu/cgi-bin/hgTables?command=start
I will try your suggestion
Thank you for your help

On Tue, 03 Jun 2008 17:14:10 -0700
 Herve Pages <[EMAIL PROTECTED]> wrote:
Hi Joseph,

Joseph Dhahbi, P.h.D. wrote:

Hi
I downloaded the drosophila RepeatMasker from UCSC GB as a text file which is in fasta format and looks like this:
dm3_rmsk_NINJA_I range=chr4:2-434 5'pad=0 3'pad=0 strand=+ repeatMasking=none
AATTCGCGTCCGCTTA......
dm3_rmsk_NINJA_LTR range=chr4:435-611 5'pad=0 3'pad=0 strand=+ repeatMasking=none
TGTCGCGGATC....
dm3_rmsk_Baggins1 range=chr4:638-1723 5'pad=0 3'pad=0 strand=- repeatMasking=none
ATACGATGG......

I made the input dictionary and I would like to make the RepeatMasker sequences as the target. When I used ‘read.DNAStringSet’ it recognized only the first sequence of the fasts file. Ho do I merge all of the sequences in and make them as a target.

If your file is really FASTA then read.DNAStringSet() should extract all the records and return a DNAStringSet object where each element corresponds to a record in the original file. So it seems like you've hit a bug in the read.DNAStringSet() function. Can you please provide the URL to the file
you downloaded so we can try to reproduce?

Anyway, what you are trying to achieve can be done in an easier (and more efficient) way. You don't need to download the RepeatMasker sequences for this; just use the BSgenome.Dmelanogaster.UCSC.dm3 package. The RepeatMasker information is already included in it as part of the built-in masks provided
for each chromosome:

  > library(BSgenome.Dmelanogaster.UCSC.dm3)
  > Dmelanogaster
  Fly genome
  |
  | organism: Drosophila melanogaster
  | provider: UCSC
  | provider version: dm3
  | release date: Apr. 2006
  | release name: BDGP Release 5
  |
  | single sequences (see '?seqnames'):
| chr2L chr2R chr3L chr3R chr4 chrX chrU | chrM chr2LHet chr2RHet chr3LHet chr3RHet chrXHet chrYHet
  |   chrUextra
  |
  | multiple sequences (see '?mseqnames'):
  |   upstream1000  upstream2000  upstream5000
  |
| (use the '$' or '[[' operator to access a given sequence)
  > chr2L <- Dmelanogaster$chr2L
  > chr2L
23011544-letter "MaskedDNAString" instance (# for masking) seq: CGACAATGCACGACAGAGGAAGCAGAACAGATATTT...GCATATTTGCAAATTTTGATGAACCCCCCTTTCAAA
  masks:
maskedwidth maskedratio active names 1 200 8.691290e-06 FALSE assembly gaps 2 1966561 8.545976e-02 FALSE RepeatMasker 3 61603 2.677048e-03 FALSE Tandem Repeats Finder [period<=12]
  all masks together:
    maskedwidth maskedratio
        1988181  0.08639929
  all active masks together:
    maskedwidth maskedratio
              0           0

Note that the built-in masks are always inactive by default. To activate
a mask do:

> active(masks(chr2L))[2] <- TRUE # activate the RepeatMasker mask

Now only the parts of chr2L that are NOT repeat regions are visible.
To invert this, use gaps():

  > chr2Lrepeats <- gaps(chr2L)
  > chr2Lrepeats
23011544-letter "MaskedDNAString" instance (# for masking) seq: #GACAATGCACGACAGAGGAAGCAGAACAGATATTT...GCATATTTGCAAATTTT###################
  masks:
    maskedwidth maskedratio active
  1    21044983   0.9145402   TRUE

Then use matchPDict() (or countPDict()) in the usual way.

The GenomeSearching vignette in the BSgenome package has more information about masking (some sections are still incomplete but
will be completed soon).

Hope this helps,
H.


Thank you for your help


Regards,
Joseph

Joseph M. Dhahbi, PhD
Childrens Hospital Oakland Research Institute
5700 Martin Luther King Jr. Way
Oakland, CA 94609
USA
Ph.(510)428-3885 EXT.5743
Cell.(702)335-0795
Fax (510)450-7910
[EMAIL PROTECTED]
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Regards,
Joseph

Joseph M. Dhahbi, PhD
Childrens Hospital Oakland Research Institute
5700 Martin Luther King Jr. Way
Oakland, CA 94609
USA
Ph.(510)428-3885 EXT.5743
Cell.(702)335-0795
Fax (510)450-7910
[EMAIL PROTECTED]
The email message (and any attachments) is for the sole...{{dropped:3}}

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