Chromosomes, the packaging units for genetic information, cannot be transmitted from generation to generation unless they interact with microtubule-based spindles. Normally, the centromere (constricted region of a chromosome) binds to the spindles. This allows the spindles to pull pairs of chromosomes apart, so that one copy of each chromosome ends up in the new, daughter cell during meiosis. This project will investigate neocentromeres, which are specialized chromosomal regions that can be used to study how chromosomes interact with spindles. In maize, neocentromeres can dramatically change genetic inheritance. One aim of this work will focus on the maize abnormal chromosome 10 that regulates natural neocentromere activity. Genes that regulate neocentromeres will be identified using a combination of modern sequencing methods. The second aim will focus on long arrays of binding sites that have been added to different positions on chromosomes arms. Known microtubule-based motor proteins (known as kinesins) will be tethered to the binding sites, causing the arrays to interact with microtubules. This novel system will make it possible to better understand how neocentromeres alter genetic inheritance. Both approaches address fundamental questions in genetics and will facilitate the development of new methods for improving crops by transgenic methods.
Broader Impacts: Maize is a classic American crop that naturally appeals to students of all ages. To broaden the impact of the research, the project includes travel and student training at a small university [Kentucky Wesleyan College (KWC)] that serves a rural farming community. Activities will include summer training for Professor Evelyn Hiatt and three undergraduates over a three-year period. Visiting undergraduate students will receive in-lab training and field experience, as well as exposure to a research setting in a major research university. The tools and methodologies used during the project will serve as a basis to improve coursework and training at KWC.