Bio::Tools tRNAscanSE
SummaryIncluded librariesPackage variablesSynopsisDescriptionGeneral documentationMethods
Summary
Bio::Tools::tRNAscanSE - A parser for tRNAscan-SE output
Package variables
No package variables defined.
Included modules
Bio::SeqFeature::Generic
Inherit
Bio::Tools::AnalysisResult
Synopsis
   use Bio::Tools::tRNAscanSE;

   my $parser = Bio::Tools::tRNAscanSE->new(-file => 'result.tRNAscanSE');

   # parse the results
   while( my $gene = $parser->next_prediction ) {

       @exon_arr = $gene->get_seqFeatures();

   }
Description
This script will parse tRNAscan-SE output. Just the tabular output of
the tRNA locations in the genome for now.
Methods
_initialize
No description
Code
gene_tagDescriptionCode
source_tagDescriptionCode
exon_tagDescriptionCode
analysis_methodDescriptionCode
next_featureDescriptionCode
next_predictionDescriptionCode
Methods description
gene_tagcode    nextTop
 Title   : gene_tag
 Usage   : $obj->gene_tag($newval)
 Function: Get/Set the value used for the 'gene_tag' of genes
           Default is 'tRNA_gene' as set by the global $GeneTag
 Returns : value of gene_tag (a scalar)
 Args    : on set, new value (a scalar or undef, optional)
source_tagcodeprevnextTop
 Title   : source_tag
 Usage   : $obj->source_tag($newval)
 Function: Get/Set the value used for the 'source_tag' of exons and genes
           Default is 'tRNAscan-SE' as set by the global $SrcTag
 Returns : value of source_tag (a scalar)
 Args    : on set, new value (a scalar or undef, optional)
exon_tagcodeprevnextTop
 Title   : exon_tag
 Usage   : $obj->exon_tag($newval)
 Function: Get/Set the value used for the 'primary_tag' of exons
           Default is 'tRNA_exon' as set by the global $ExonTag
 Returns : value of exon_tag (a scalar)
 Args    : on set, new value (a scalar or undef, optional)
analysis_methodcodeprevnextTop
 Usage     : $genscan->analysis_method();
 Purpose   : Inherited method. Overridden to ensure that the name matches
             /tRNAscan-SE/i.
 Returns   : String
 Argument  : n/a
next_featurecodeprevnextTop
 Title   : next_feature
 Usage   : while($gene = $genscan->next_feature()) {
                  # do something
           }
 Function: Returns the next gene structure prediction of the Genscan result
           file. Call this method repeatedly until FALSE is returned.

           The returned object is actually a SeqFeatureI implementing object.
           This method is required for classes implementing the
           SeqAnalysisParserI interface, and is merely an alias for 
           next_prediction() at present.

 Example :
 Returns : A Bio::SeqFeature::Generic object.
 Args    :
See also : Bio::SeqFeature::Generic
next_predictioncodeprevnextTop
 Title   : next_prediction
 Usage   : while($gene = $genscan->next_prediction()) {
                  # do something
           }
 Function: Returns the next gene structure prediction of the Genscan result
           file. Call this method repeatedly until FALSE is returned.

 Example :
 Returns : A Bio::SeqFeature::Generic object.
 Args    :
See also : Bio::SeqFeature::Generic
Methods code
_initializedescriptionprevnextTop
sub _initialize {
  my($self,@args) = @_;
  $self->SUPER::_initialize(@args);
  my ($genetag,$exontag,$srctag) =  $self->SUPER::_rearrange([qw(GENETAG
								 SRCTAG
								 EXONTAG)],
							      @args);
  $self->gene_tag(defined $genetag ? $genetag : $GeneTag);
  $self->source_tag(defined $srctag ? $srctag : $SrcTag);
  $self->exon_tag(defined $exontag ? $exontag : $ExonTag);
  $self->{'_seen'} = {};
}
gene_tagdescriptionprevnextTop
sub gene_tag {
    my $self = shift;

    return $self->{'gene_tag'} = shift if @_;
    return $self->{'gene_tag'};
}
source_tagdescriptionprevnextTop
sub source_tag {
    my $self = shift;

    return $self->{'_source_tag'} = shift if @_;
    return $self->{'_source_tag'};
}
exon_tagdescriptionprevnextTop
sub exon_tag {
    my $self = shift;

    return $self->{'_exon_tag'} = shift if @_;
    return $self->{'_exon_tag'};
}
analysis_methoddescriptionprevnextTop
sub analysis_method {
 #-------------
    my ($self, $method) = @_;  
    if($method && ($method !~ /tRNAscan-SE/i)) {
	$self->throw("method $method not supported in " . ref($self));
    }
    return $self->SUPER::analysis_method($method);
}
next_featuredescriptionprevnextTop
sub next_feature {
    my ($self,@args) = @_;
    # even though next_prediction doesn't expect any args (and this method
    # does neither), we pass on args in order to be prepared if this changes
    # ever
    return $self->next_prediction(@args);
}
next_predictiondescriptionprevnextTop
sub next_prediction {
    my ($self) = @_;
    my ($genetag,$srctag,$exontag) = ( $self->gene_tag,
				       $self->source_tag,
				       $self->exon_tag);

    while( defined($_ = $self->_readline) ) {
	if( m/^(\S+)\s+       # sequence name
	    (\d+)\s+          # tRNA #
	    (\d+)\s+(\d+)\s+  # tRNA start,end
	    (\w{3})\s+        # tRNA type
	    ([CAGT]{3})\s+    # Codon
	    (\d+)\s+(\d+)\s+  # Intron Begin End
	    (\d+\.\d+)/ox     # Cove Score
	    ) {
	    
	    my ($seqid,$tRNAnum,$start,$end,$type,
		$codon,$intron_start,$intron_end,
		$score) = ($1,$2,$3,$4,$5,$6,$7,$8,$9);
	    
	    my $strand = 1;
	    if( $start > $end ) { 
		($start,$end,$strand) = ($end,$start,-1);
	    }
	    if( $self->{'_seen'}->{"$seqid.$type"}++ ) {
		$type .= "-".$self->{'_seen'}->{"$seqid.$type"};
	    }
	    my $gene = Bio::SeqFeature::Generic->new
		( -seq_id => $seqid,
		  -start  => $start,
		  -end    => $end,
		  -strand => $strand,
		  -score  => $score,
		  -primary_tag => $genetag,
		  -source_tag  => $srctag,
		  -tag     => {
		      'ID'    => "tRNA:$type",
		      'AminoAcid' => $type,
		      'Codon'     => $codon,
		  });
	    if( $intron_start ) {
		if( $intron_start > $intron_end ) {
		    ($intron_start,$intron_end) = ($intron_end,$intron_start);
		}
		$gene->add_SeqFeature(Bio::SeqFeature::Generic->new
				      ( -seq_id=> $seqid,
					-start => $start,
					-end   => $intron_start-1,
					-strand=> $strand,
					-primary_tag => $exontag,
					-source_tag  => $srctag,
					-tag => { 
					    'Parent' => "tRNA:$type" 
					    }));
		$gene->add_SeqFeature(Bio::SeqFeature::Generic->new
				      ( -seq_id=> $seqid,
					-start => $intron_end+1,
					-end   => $end,
					-strand=> $strand,
					-primary_tag => $exontag,
					-source_tag  => $srctag,
					-tag => { 
					    'Parent' => "tRNA:$type" 
					    }));
	    } else {
		$gene->add_SeqFeature(Bio::SeqFeature::Generic->new
				      ( -seq_id=> $seqid,
					-start => $start,
					-end   => $end,
					-strand=> $strand,
					-primary_tag => $exontag,
					-source_tag  => $srctag,
					-tag => { 
					     'Parent' => "tRNA:$type" 
					     }));
	    }
	    return $gene;
	} 
    }
}
General documentation
FEEDBACKTop
Mailing ListsTop
User feedback is an integral part of the evolution of this and other
Bioperl modules. Send your comments and suggestions preferably to
the Bioperl mailing list. Your participation is much appreciated.
  bioperl-l@bioperl.org                  - General discussion
  http://bioperl.org/wiki/Mailing_lists  - About the mailing lists
Reporting BugsTop
Report bugs to the Bioperl bug tracking system to help us keep track
of the bugs and their resolution. Bug reports can be submitted via the
web:
  http://bugzilla.open-bio.org/
AUTHOR - Jason StajichTop
Email jason-at-bioperl.org
APPENDIXTop
The rest of the documentation details each of the object methods.
Internal methods are usually preceded with a _
newTop
 Title   : new
 Usage   : my $obj = new Bio::Tools::tRNAscanSE();
 Function: Builds a new Bio::Tools::tRNAscanSE object 
 Returns : an instance of Bio::Tools::tRNAscanSE
 Args    : -fh/-file for input filename
           -genetag => primary tag used in gene features (default 'tRNA_gene')
           -exontag => primary tag used in exon features (default 'tRNA_exon')
           -srctag  => source tag used in all features (default 'tRNAscan-SE')