Trevor Dale of Cardiff University... has come up with a way that proteins and RNA might catalyse each other's production.I'll add other links as I find them. Off to bed.
The protein involved would crystallise in the form of long, and easily formed, fibres called amyloid. (This is the form that proteins take in brain diseases such as Alzheimer's and Creutzfeldt-Jakob.) The amyloid fibres would then act as surfaces on which RNA molecules could grow.
Crucially, RNA forming on a fibre this way would grow as double strands, like the DNA in a cell nucleus, rather than as the single strands in which the molecule normally comes. When the strands separated, each would act as a template for a new double-stranded molecule, just as happens when a DNA molecule divides.
The protein, meanwhile, would grow because the protruding end of the RNA would act as a catalyst, adding amino acids on to the end of the amyloid fibre. When the fibre grew too long to be stable, it would break in two. Thus both RNA and protein would replicate.
Such a system, Dr Dale thinks, could be the ancestor of the ribosome and, if wrapped in a fatty membrane, of the cell. And, as David Deamer, of the University of California, Santa Cruz, told the meeting, such membranes will assemble spontaneously in certain conditions.
Dr Dale's idea is certainly chemically plausible, though it has yet to be tested in a laboratory. But he is conducting tests at the moment, and hopes to have the results later this year.
(added)
Dr. Dale's homepage is here; he's also involved in cancer research. Read the abstract to the paper in question here.
1 comment:
You know how Kellog's and White Castle will sponsor contests to think up recipes for things you can make with Rice Crispies or with those little hamburgers? I believe the same sort of phenomenon happens in the culture of science. There's bazillions of dollars funding amyloid research, because amyloid is the smoking gun for Alzheimer's. But there are only so many natural lines of inquiry to pursue, and too many people pursuing them. So some zany ideas for what one can hypothesize about amyloid are bound to be proposed. What's more, the media are bound to report it, because amyloid is "hot" and nobody's making any real progress. That said, I haven't read the paper in question. My instinctive inner scientist just says "Rice Crispie marshmallow pie."
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