In a (now trashed) thread, Moontanman linked to an interesting story about the role of retroviruses in brain function and memory:

That was a very poorly written article (in one sentence, I couldn't even work out what the "it" referred to). But it still looked like very interesting, so here is a better one (with references to the original papers): https://www.nature.com/articles/d41586-018-00492-w

Quote

A pair of papers^1,2 published in Cell on 11 January suggest that the protein encoded by one such gene uses its virus-like structure to shuttle information between cells: a new form of cellular communication that may be key to long-term memory formation and other neurological functions.

 

 

I wonder if other tissues use the same methods to communicate between cells. It's really interesting topic. I'm looking forward to seeing other studies about it.