Welcome to the E. Desmond Lee and Family Molecular Biology Laboratory
at the University of Missouri St. Louis
How did evolution
produce so many different kinds of plants?
Evolution has produced over a quarter of a million different sorts of flowering plants. In general, this is caused by a complex interaction of the environment with the genes of the plants. I'm particularly interested in the genes that have changed to produce the many different sorts of plant structures that we see today. My research focus is the grass family, a group that includes about 10,000 different species. Among these are maize, wheat, and rice, the so-called "Big Three" crops that feed most people in the world.
These three grasses are very distantly related; their most recent common ancestor may have lived as much as 50 million years ago. If we can understand the sorts of genetic changes that occurred in those 50 million years, we can understand how the grasses evolved into thousands of different species and how the major grains differ from each other. That knowledge could help us understand the factors that control productivity of crops.
We use multiple methods to investigate the
evolution of grasses. One approach is genealogical, using gene
sequences to determine the evolutionary tree so we know which
grasses are most closely related to each other. A second approach
is developmental, using the scanning electron microscope to see
exactly how the various species grow and how they differ from
each other. A third approach is genetic, crossing closely related
species to determine how many genes vary between them. The fourth
approach is genomic, studying genes that are well-known in maize
and rice, and investigating how they are deployed in other minor
crops and wild grasses. None of the four approaches is sufficient
alone, but the combination enables us to dissect the intricate
pattern of grass evolution.