So that's really one approach: to look at mutants and ask questions about what the mechanism of those mutations and the effect of those mutations on plant development is. The other approach is to look at the genome first and then to see what effects on the genome you can find that might explain some of these developmental issues. That's much more difficult, but nowadays it's possible because we have a complete [genome] sequence of Arabidopsis, which is probably the most significant event in plant genetics since McClintock's discovery of transposable elements. Actually it's that ability to be able to see the distribution of transposable elements in the genome that's really key to the way in which we're thinking about this. Many of the epigenetic mechanisms we're studying in development impact transposable elements. In fact, there's a school of thought, one that I belong to, which says that epigenetics itself is really at least evolved from transposons, if not tied in directly to how transposons are regulated in the genome. This is really getting back to McClintock's original view of controlling elements and their role in heterochromatin, chromosome organization, and in gene expression and plant development. And so we're now trying to make those sorts of correlations by looking at the whole genome, by using genome technologies like micro arrays and other modem technologies, to see how transposons and heterochromatin are affected by these mutants. And so we have mutants in chromatin remodeling, we have mutants in methylation, we have mutants in RNA-i and we're now able to take whole genome approaches to find out what effect they're really having on the cell.

This is a very exciting time to be a part of plant genetics. It's amazing, actually, what we have, all these resources, now. It's fun being part of the Arabidopsis genome project, too. It was a great event. It took only five years to complete the genome, when it was supposed to take much longer. It was done in the spirit of international cooperation, which was really unparalleled in genome projects, which had tended to be rather contentious. I'm sure you'll here that from the other genome people. But the Arabidopsis genome project was really done very quickly and done very cooperatively and it was really a great experience just to be part of that.

Dr. Robert Martiennsen is a plant biologist, Howard Hughes Medical Institute-Gordon and Betty Moore Foundation investigator, and professor at Cold Spring Harbor Laboratory. Martiennsen attended Emmanuel College, Cambridge, completing his BA in 1982 and continuing on to his PhD in 1986 on the molecular genetics of alpha-amylase gene families in common wheat. He received an EMBO postdoctoral fellowship with University of California, Berkeley. In 1989, he was hired as a principal investigator at Cold Spring Harbor Laboratory. As a young scientist, he worked closely with Barbara McClintock. His awards and honors include the Newcomb Cleveland Prize, McClintock Prize, and Science’s Breakthrough of the Year in 2002 and the Kumho International Science Award in Plant Biology and Biotechnology (2001).