This Plant Genome project aims to provide "proof of concept" for constructing a cytological physical map of the maize genome and relating this map to the genetic and DNA physical maps being constructed by other investigators. A major goal will be to construct 50 new B-A-A translocation stocks each year over the three-year course of the project. These new cytogenetic stocks will utilize two valuable resources unique to maize: a large collection of A-A reciprocal translocations (where terminal regions of chromosome have exchanged with each other), and a collection of simple B-A translocation stocks. These latter translocations involve exchanges between the normal A chromosomes and the supernumerary B chromosomes. These stocks exhibit a peculiar cell division during pollen formation so that they can be used to locate genes along the chromosome arms. By bringing these two types of translocations together in the same plants it will be possible to obtain progeny containing recombinants between them. The resulting new B-A-A compound translocations will be used to subdivide selected maize chromosomes into small cytologically defined regions. The analysis will focus on chromosome arms 1S, 5S, 6L and 10S but will also include other regions. A high level of recovery of new B-A-A stocks expected. In addition, molecular mapping techniques will be used to align the cytologically defined chromosome regions to the genetic and physical maps of maize using molecular probes already identified on these maps. By the third year of the project the new B-A-A stocks will have been verified and an estimated 60 to 80 should be deposited at the Maize Sock Center for distribution to interested investigators. A Web address is being created www.BAAtrans.und.edu where the public can get information on the project including accessing mapping data for the new B-A-A stocks. This project will aid the overall maize community objectives by providing a powerful set of cytogenetic analytical tools and by proving their usefulness in both the molecular mapping of the maize genome and in the molecular cytogenetic localization of individual genes to narrowly defined chromosome segments. This project will broaden the participation of American Indian students in biology and it will strengthen the research infrastructure at the University of North Dakota. By placing all results and deliverables in the public domain this project will serve society's need for free and open scientific communication.
