Very useful information, thanks! So, for completeness, you could do it like this:
for file in Mouse/mmu_piR_*; do grep ">" $file | awk -v OFS="\t" -F: '{print "chr"$2,$3,$4,$1,"1",$5}'; done | sed -e 's/Plus/+/g' -e 's/Minus/-/g' |awk 'NF > 0'| sort -k1,1 -k2,2n > mm8_piRNA.bed
Note that the coordinates in the archive appear to be from NCBIM36 (mm8) and not from mm9 (at least the few ones that I checked individually).
Can you tell more detail? Now I happened to need these coordinates in GRCm37 (mm9).
You can just use liftOver from UCSC to convert mm8 to mm9 coordinates.
http://pirnabank.ibab.ac.in/ seems to be down. Is there any other database link?
Thanks
i figure out how to download it ,go to ncbi nucleotide ,search piRNA and your species
As majority of the answers, pirna is usualy downloaded from pirnabank. All the coordination is quit old, for human is hg18 and for mice is mm8.
http://pirnabank.ibab.ac.in/request.html
However, if you blast these sequences and you will find the coordination is not perfect matched.
Take human piwi-RNA as example:
if you make a blast with UCSC you will find:
Everyone should think about how to deal with this problem.