Date: Around 1993
How does messenger RNA work?
mRNA attaches to an organelle in the cytoplasm called the
ribosome. For each amino acid that will eventually end up in the final
protein, there is a small separate RNA molecule called transfer, or t, RNA.
The mRNA is "read" in order. First the tRNA molecule that matches the first 3
base pairs on the mRNA attaches to the mRNA on the ribosome, bringing its
amino acid with it. Then the next 3 bases on the mRNA are read, and a second
tRNA attaches to the mRNA, bringing its amino acid with it. This hooks up to
the first amino acid, thus beginning the protein chain. And so on until the
end. At the end, the mRNA has a three base sequence that terminates the
process and releases the protein to be sent to wherever it goes in the cell.
The mRNA can be "translated" in this way more than once to produce more than
one identical proteins.
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Update: June 2012