Edward H. Coe

Research

Our group carried out a large plant genome project, “Comprehensive Genetic, Physical, and Database Resources for Maize,” supported by the National Science Foundation. This Maize Mapping Project was begun in 1998. The team produced high-resolution genetic maps with many new molecular markers, and cross-linked the genetic maps to physical maps developed by fingerprinting and molecular markers. Large numbers of new markers have been developed and have been placed on a genetic map whose resolution is 0.05 centiMorgans, equivalent to about 70,000 base pairs on average. Three BAC libraries, totaling over 27X deep, have been made available for research. The BACs are fingerprinted and are anchored with molecular markers. This well-supported, integrated map is the base upon which sequencing of the maize genome, now in progress, can be done.

I continue to focus on mapping mutants of maize. Genetic analysis of variants and mutant expressions, joined with mapping of expressed sequences, reveals their candidacy for biochemically defined functions. Cellular strategies in growth and development can be tested that include control of what function occurs when, where, under which condition, and to what extent, a function occurs. Each of these contributes valuable knowledge on the biology and the productivity of this plant and of other cereals. In mutants, failure of the right event at the right time is sometimes lethal, sometimes simply abnormal, sometimes striking and intensely informative.

The Maize Genome Database, which was designed and assembled in this laboratory, is an ongoing, comprehensive source of information on the genetics and molecular biology of maize. This database, a service of USDA/ARS, is currently conducted cooperatively by Iowa State University and in the University of Missouri-Columbia. It depends upon, draws together, and links to data, information, and other web sites from national and international maize projects and publications. Included are gene descriptions, maps, genomic sequences, and a wide range of images of maize seedlings, plants, tassels, ears, kernels, and mutants that affect them.