There has been a lot of scientific interest in the protein alpha-synuclein and its probable role in Parkinson’s recently. I put together a few notes on the background for a post about one such study, and then realised that they might be better in a spearate post that I could refer to from other potential posts concerned with the protein.
The protein alpha-synuclein is known to be implicated in Parkinson’s. It can be found in cells all over the body, but is concentrated in neural tissue in the brain. Normally, it exists in an unstructured, soluble form, but in Parkinson’s (and other conditions), it forms clumps inside the dopamine-producing neurons. These clumps, or aggregates, are known as Lewy bodies.
It is believed that these Lewy bodies are “aggresomes“, that is, an accumulation of protein that should have been disposed of. They consist mainly of alpha-synuclein, but there are also a few other proteins in there. They may be toxic to nerve cells; research suggests that, once the Lewy bodies appear in the nerve cells, the nerve cells cease to work properly, and eventually die.
There may be more to the role of alpha-synuclein than Lewy bodies; some research indicates that the protein may be important in ensuring that dopamine is released by the nerve cells in the proper manner. Nerve cells with Lewy bodies present have less alpha-synuclein than equivalent healthy cells; a study funded by Parkinson’s UK is looking into the implications of reduced levels of the protein where Lewy bodies are not present. Genetic evidence also indicates that alpha-synuclein is important; inherited variations in the gene for the protein can lead to young-onset Parkinson’s.