1
Some mRNA (or DNA if replace U with T)
cacgccugcaggucgacucuagaggauccccggguaccggucgccaccauggugagcaag
ggcgaggagcuguucaccgggguggugcccauccuggucgagcuggacggcgacguaaac
ggccacaaguucagcguguccggcgagggcgagggcgaugccaccuacggcaagcugacc
cugaaguucaucugcaccaccggcaagcugcccgugcccuggcccacccucgugaccacc
cugaccuacggcgugcagugcuucagccgcuaccccgaccacaugaagcagcacgacuuc
uucaaguccgccaugcccgaaggcuacguccaggagcgcaccaucuucuucaaggacgac
ggcaacuacaagacccgcgccgaggugaaguucgagggcgacacccuggugaaccgcauc
gagcugaagggcaucgacuucaaggaggacggcaacauccuggggcacaagcuggaguac
aacuacaacagccacaacgucuauaucauggccgacaagcagaagaacggcaucaaggug
aacuucaagauccgccacaacaucgaggacggcagcgugcagcucgccgaccacuaccag
cagaacacccccaucggcgacggccccgugcugcugcccgacaaccacuaccugagcacc
caguccgcccugagcaaagaccccaacgagaagcgcgaucacaugguccugcuggaguuc
gugaccgccgccgggaucacucucggcauggacgagcuguacaaguaaagcggccgcgac
which contains the gene for this protein
MVSKGEELFTGVVPILVELDGDVNGHKFSVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTLTY
GVQCFSRYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKED
GNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHY
LSTQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK
Where does the protein start in the mRNA? Where does it end?
http://arbl.cvmbs.colostate.edu/molkit/index.html
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Here is a tool for translation of DNA into protein. This one is nice because it gives a graphical output that
can be quickly interpreted.
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http://arbl.cvmbs.colostate.edu/molkit/index.html
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Paste your DNA or RNA sequence into the box.
http://arbl.cvmbs.colostate.edu/molkit/index.html
3
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Here is the output for the DNA sequence provided earlier.
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There are 6 reading frames, the 3 forward and 3 reverse frames. Which one looks like the most
reasonable sequence, given that this sequence is supposed to encode a protein?
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Little green lines represent start codons, while little purple lines represent stop codons.
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A line that is littered in purple probably does not encode a protein (e.g. reverse #3). Forward frame #2
could, in principle, encode one very small peptide.
A line with no green dashes can not be a protein since there is no ‘start’ signal (e.g. forward #3).
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The correct reading frame is frame #1. Extra green dashes are okay, these simply represent methionine
residues in the protein.
www.expasy.org (rerouted to ca.expasy.org)
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4
The ExPASy translate tool is generally more useful than the previous one if the actual sequence of the
protein is desired.
http://ca.expasy.org/tools/dna.html
Verbose/compact/include nucleotide
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http://ca.expasy.org/tools/dna.html
6
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The results of translation were obtained in the ‘compact’ mode
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The graphical results and the detailed sequence results present exactly the same information, just in a
different format. For example, anywhere that there is a green dash in the figure, there should be an ‘M’ in
the sequence
http://ca.expasy.org/tools/dna.html
7
•Include nucleotide give 3 forward and 3 reverse translations
•Only 2 translations are shown:
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This is the ‘include nucleotide’ mode. Generally speaking, this mode is the most useful for molecular
biology applications.