Monday, October 02, 2006

Discoverers of cellular “SHUT UP!” signals win Nobel!

Sweet! I remember when I first learned about siRNA—Fall of my senior year of college—Molecular Genetics—‘Control of Leaf Morphogenesis by microRNAs’.

As hard as my professor tried, I just didnt 'get' it at first. RISCs, Dicers, Pri-miRNA, Pre-miRNA-- The whole process is elegantly insane! Single stranded siRNA goes out into the cell and binds to its exact complement creating a double-stranded RNA. Double-stranded RNA is a magnent for this complex that rips the dsRNA apart. Its one of the ways your genome keeps all those endogenous retroviruses quiet ;)

This animation explains it much better than I can!

Isnt it nuts!! No wonder it took us so long to find it!

Its turned out to be not just an interesting process, but an absurdly useful tool as well. Plants, animals, insects, fungi, viruses, everybody has non-protein-coding sequences in their DNA that code for silencing RNA-- so that means that we can design an artificial 'siRNA' for a gene we're interested in, in basically any organism, and see what happens when we make the gene shut up!

Its so much more practical than mutating a gene so its not expressed all to see what happens. Sometimes when you totally knock out a gene, the organism cant even develop right, so youre no closer to understanding the gene fuction than you were before. But again, with siRNA, you can let the organism grow up and only silence a gene to see what happens, and then when all the siRNA is degraded, you can see what happens when the gene fuction is restored! Its a natural process that we can harness.


But Im kinda sad my pick didn’t win. I was partial to Roger Tsien because one of my research projects is all about making things glow. Tsiens lab made a billion new fluorescent proteins:




Well, I appreciate the ability to make my viruses in Skittles colors.

No comments: