18th Annual Student Research Conference
Science
Mitochondrial DNA Insertion into Nuclear Chromosomes of Maize
Ashley N. Lough
Dr. Kathleen J. Newton (University of Missouri- Columbia), Dr. James A. Birchler (University of Missouri- Columbia), Dr. Diane Janick-Buckner, and Dr. Brent Buckner, Faculty Mentors
Over evolutionary time, the transfer of genes from the mitochondrion to the nucleus has proceeded to a degree that mitochondria now require nuclear genes to function. Our study suggests that this DNA transfer is ongoing in maize. Using fluorescence in situ hybridization we identified the locations of mitochondrial DNA within the nuclear chromosomes of the B73, B37, Mo17 and Black Mexican Sweet (BMS) lines. Twelve cosmids, representing over 70% of the NB mitochondrial genome, were fluorescently labeled and hybridized to root tip chromosomes. In B73, we identified 8 different insertion sites on chromosomes 2, 3, 4, 7 and 9, predominantly near centromeres and telomeres. Interestingly, the insertions sites detected were not consistent among the examined lines. Although each line showed 6 to 8 insertion sites, only chromosome 2 was labeled in all 4 lines. This result raises the possibility that mitochondrial DNA sequences were recently and independently transferred into nuclear DNA of different maize lines.
Keywords: maize, mitochondria , gene transfer, fluorescence , hybridization, insertions
Topic(s):Biology
Presentation Type: Poster
Session: 29-63
Location: OP Lobby & Atrium
Time: 1:15