by Matthew Cobb
Jerry suggested I post the following piece as a signing-off for my current stint as co-guest blogger.
The British media has started to fill its pages and programmes with retrospective pieces on the last decade – the noughties, as media types (but nobody else) calls them. For example, The Guardian carried this set of articles this weekend. Amongst the predictably true stuff about Google, iPods and 9/11, and the parochial British obsession with z-list celebrities, there was a brief piece about the key scientific discoveries of the noughties. So this was my question to Jerry:
What were the three most important biological discoveries of the noughties?
My list would be: Homo floresiensis (aka The Hobbit), the Human Genome (even though that’s not really a discovery, but an inevitable application of a technique) and, in an area I’m particularly familiar with, the discovery and continual re-discovery of insect olfactory receptors.
In 2000, three groups finally described insect olfactory receptors. The vertebrate equivalents had been isolated in 1991 by Linda Buck and Richard Axel, who went on to win the Nobel Prize in 2004. The gap in time was surprising, and was initially put down to the fact that, even in closely related species, olfactory receptors evolve extremely quickly, so looking for genetic sequences in insect genomes that were similar to vertebrate olfactory receptors was a tricky business.
But it soon turned out that things were even more complicated. In 2006, Richard Benton, a post-doctoral researcher in Leslie Vosshall’s lab in Rockefeller, showed that in fact insect olfactory receptors are completely different from their vertebrate equivalents. They are literally upside down – the bits that people thought were outside the cell, interacting with smells, turned out to be inside, connected to the machinery that makes the neuron fire.
Furthermore, Vosshall’s group showed that these receptors only worked if they had a co-factor, which is incredibly highly conserved in insect species. You can take the gene from a moth and stick it in a mutant fly, and the fly will smell again, even though lepidoptera and diptera are separated by about 200 million years of evolution.
Not content with making one stunning discovery, Benton and Vosshall made another at the beginning of the year. Shortly before leaving Rockefeller to set up a new group in Lausanne, Switzerland, Benton discovered a completely new class of olfactory receptor in insects, which works in a completely different way from previously-identified insect receptors and has a completely separate evolution.
In unpublished work his lab presented last week at a meeting I attended in Switzerland, he shows that this class of receptor is common to all studied protostomes (essentially the invertebrates, minus the sea urchins and some worms), but is absent from all deuterostomes (all other animals). You can track the path of evolution by the way that animals smell the outside world, and these ways are turning out to be incredibly rich and complex.
Benton himself is not only a very pleasant and incredibly modest young man (with not much to be modest about!), he is someone who having made some fundamental discoveries in cutting edge molecular neurobiology, recognises the fundamental importance of putting those findings into an evolutionary and ecological context. As Theodosius Dobzhansky put it, “Nothing in biology makes sense except in the light of evolution”.
You can read more about Benton’s work in this prize-winning essay, recently published in Science, in an open access section.
So – what would the readers of this blog (and Jerry) think were the three most important findings in biology in the noughties?