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Abstract
The genomes of maize and its wild relatives in the genus Zea are regarded widely for their genotypic and phenotypic diversity. The two major overarching biological themes in this dissertation relate to phenomena that evolved within teosinte genomes long before the domestication of maize. Maize exhibits a preferential segregation system that is genetically transmitted through a variant of the chromosome 10 haplotype referred to as Abnormal chromosome 10 (Ab10). Ab10 elicits meiotic drive by manipulating the process of female meiosis. This phenomenon occurs through a mechanism whereby genomic regions composed of heterochromatic tandem repeats known as knobs become motile during meiosis. Knobs can be composed of two types of tandem repeats. The active motile forms of knobs are called neocentromeres and genetic control over the two types of neocentromeres is controlled by distinct loci which we have characterized in this work. Both loci encode kinesin-14 motor proteins that interact with knob repeats and pull them towards the minus-end poles during anaphase I and II of meiosis. The major class of knob repeats, knob180, is controlled by the kinesin-14 motor, KINDR. KINDR undergoes an indirect interaction with knob180 knobs and this interaction may be facilitated by a newly-identified kinesin-10-like protein that is encoded near Kindr on the Ab10 distal tip. Motility for the second class of knob repeats, TR-1, is controlled by another kinesin-14 protein called TRKIN. KINDR and TRKIN are not directly related and TRKIN is highly divergent from its closest maize homolog. Future work on the Ab10 kinesin-14s may help elucidate this mechanism of meiotic drive and how the two neocentromere systems interplay during this process. The other focus of this dissertation pertains to the perennial growth habit seen in the teosinte species Zea diploperennis. Annual maize (Z. mays ssp. mays) lines were crossed with Z. diploperennis and perennial regrowth was assessed in the F2 population. Using QTL-seq and PCR genotyping of individual plants, regrowth was significantly associated with two loci located on chromosomes 2 and 8. Back-crossed and RIL populations may be used in the future to more precisely map the locations of these loci.