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Here are some examples that you might want to try out. The
executables of course should be installed before hand somewhere in
your path. Or you can call them as ../bin/genewise etc if you haven't
installed them.
If you get warnings like
Warning Error
Could not open codon.table
then you haven't set the WISECONFIGDIR enviroment variable.
You can set it now by going
setenv WISECONFIGDIR ../wisecfg
Print out the wise2 documentation (docs/wise2.ps) and read
the 'Introduction for the impatient user'
Here are some examples:
a) Comparing a protein sequence to a genomic clone
genewise road.pep hngen.fa
(the protein is from drosophila)
b) Comparing a protein HMM to a genomic clone
genewise -hmmer rrm.HMM hngen.fa
c) Try the following options on either a) or b)
-kbyte XXXX where XXXX is the maximum amount of memory
on your machine
-genes - gives gene prediction output
-trans - gives translations of the predicted genes
-embl - give EMBL format Feature table output
do genewise -help and have a look at other formats you
could make
d) try
genewise -hmmer rrm.HMM hngen.fa -alg 2193L
for the most complicated algorithm genewise has to offer.
For comparisons using ESTs
a) protein to est
estwise road.pep hn_est.fa
Notice the frameshift with the ! in the translation
b) profile HMM to est
estwise -hmmer rrm.HMM hn_est.fa
For database comparisons
a) an dna sequence against a database of profile HMMs
estwisedb -pfam db.hmm vav.dna
or
genewisedb -pfam db.hmm vav.dna
----------------------------------------------------------------
Using dba. dba (Dna Block aligner) compares two DNA sequences
trying to find co-linear blocks of homology with the potential
of a small number of gaps but with large intervening sequences
between the blocks of variable length.
The idea is to be able to find regulatory regions in non coding
sequences from different species.
For example, using the first intron from keratin18 genes from
mouse and human gives the following output:
adnah:[/wise2/example]<53>: ../bin/dba keratin_intron.human keratin_intron.mouse
score = 72.52
56 140 109 192 69% 3 gaps, MATCH_A
321 395 358 431 89% 1 gaps, MATCH_C
401 496 467 559 70% 3 gaps, MATCH_A
560 579 593 613 95% 1 gaps, MATCH_D
622 691 646 712 80% 5 gaps, MATCH_B
This indicates that there are 5 blocks of homology. The blocks are
parameterised into homology levels being (when run using the default
parameters)
A approx 60-70% identity
B approx 70-80% identity
C approx 80-90% identity
D approx 90-100% identity
The approximation is due to the fact that the models are parameterised
probabilistically with gaps being taken into account. The probabilites
for the different blocks are by default
A 0.65
B 0.75
C 0.85
D 0.95
(each probability representing the probability of finding a idenity
pair in the block).
By and large blocks around the identity range will fall into the
correct homology block, but the interplay of the parameters about
block probability means that the calculated %idenity need not fall
into the expected block type.
The -align option is very verbose and probably not that useful.
dba has been intergrated into the alfresco java viewer. In alfresco
you can interactively decide what regions to compare and shows the
results integrated with other analysis, eg repeats. Alfresco (and
dba) was written by Niclas Jareborg. A web site for it is at
http://www.sanger.ac.uk/Software/Alfresco
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