Description
This track displays tRNA genes predicted by using
tRNAscan-SE v.1.23.
tRNAscan-SE is an integrated program that uses tRNAscan (Fichant) and an A/B box motif detection
algorithm (Pavesi) as pre-filters to obtain an initial list of tRNA candidates.
The program then filters these candidates with a covariance model-based
search program
COVE (Eddy) to obtain a highly specific set of primary sequence
and secondary structure predictions that represent 99-100% of true tRNAs
with a false positive rate of fewer than 1 per 15 gigabases.
Detailed tRNA annotations for eukaryotes, bacteria, and archaea are available at
Genomic tRNA Database (GtRNAdb).
What does the tRNAscan-SE score mean? Anything with a score above 20 bits is likely to be
derived from a tRNA, although this does not indicate whether the tRNA gene still encodes a
functional tRNA molecule (i.e. tRNA-derived SINES probably do not function in the ribosome in translation).
Vertebrate tRNAs with scores of >60.0 (bits) are likely to encode functional tRNA genes, and
those with scores below ~45 have sequence or structural features that indicate they probably are
no longer involved in translation. tRNAs with scores between 45-60 bits are in the "grey" zone, and may
or may not have all the required features to be functional. In these cases, tRNAs should be inspected
carefully for loss of specific primary or secondary structure features (usually in alignments with other
genes of the same isotype), in order to make a better educated guess. These rough score range guides
are not exact, nor are they based on specific biochemical studies of atypical tRNA features,
so please treat them accordingly.
Please note that tRNA genes marked as "Pseudo" are low scoring predictions that are mostly pseudogenes or
tRNA-derived elements. These genes do not usually fold into a typical cloverleaf tRNA secondary
structure and the provided images of the predicted secondary structures may appear rotated.
Credits
Both tRNAscan-SE and GtRNAdb are maintained by the
Lowe Lab at UCSC.
Cove-predicted tRNA secondary structures were rendered by NAVIEW (c) 1988 Robert E. Bruccoleri.
References
When making use of these data, please cite the following articles:
Chan PP, Lowe TM.
GtRNAdb: a database of transfer RNA genes detected in genomic sequence.
Nucleic Acids Res. 2009 Jan;37(Database issue):D93-7.
PMID: 18984615; PMC: PMC2686519
Eddy SR, Durbin R.
RNA sequence analysis using covariance models.
Nucleic Acids Res. 1994 Jun 11;22(11):2079-88.
PMID: 8029015; PMC: PMC308124
Fichant GA, Burks C.
Identifying potential tRNA genes in genomic DNA sequences.
J Mol Biol. 1991 Aug 5;220(3):659-71.
PMID: 1870126
Lowe TM, Eddy SR.
tRNAscan-SE: a program for improved detection of transfer RNA genes in genomic sequence.
Nucleic Acids Res. 1997 Mar 1;25(5):955-64.
PMID: 9023104; PMC: PMC146525
Pavesi A, Conterio F, Bolchi A, Dieci G, Ottonello S.
Identification of new eukaryotic tRNA genes in genomic DNA databases by a multistep weight matrix
analysis of transcriptional control regions.
Nucleic Acids Res. 1994 Apr 11;22(7):1247-56.
PMID: 8165140; PMC: PMC523650
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