In particular, Parkinson's is associated with a lack in the brain of a messenger molecule called dopamine.

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This illness is caused by low levels of a messenger molecule called dopamine in certain parts of the brain.

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The message itself is copied into a single-stranded messenger molecule which carries it to the protein-making parts of the cell, where it is translated.

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When a cell translates a gene into a protein, it uses a messenger molecule that carries the genetic information to a protein factory called a ribosome.

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Having created a morpholino for the env messenger molecule, Dr Dunlap injected it into a series of ewes eight days after they had mated and sat back to see what would happen.

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Scientists have looked at anger and violence, though, and discovered genetic variations, expressed as concentrations of a particular messenger molecule in the brain, that are both congenital and predisposing to a violent temper.

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These trigger the degradation of another type of RNA molecule known as messenger RNA (mRNA), "down-regulating" the gene.

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The bacteria interacts with a molecule called IL-8 which should act as the messenger to rally other parts of the immune system to attack the "invader".

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It was a stretch of DNA that could be transcribed by an enzyme called polymerase into a chemically similar molecule known as RNA. The RNA acted as a messenger that was itself translated into protein molecules in sub-cellular factories called ribosomes.

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