19th Annual Student Research Conference
Science
DNA Sequence Diversity of the Zeaxanthin Epoxidase Paralogs Among Inbred Lines and Open-pollinated Landraces
Heath A. Smith
Dr. Brent Buckner and Dr. Diane Janick-Buckner, Faculty Mentors
Zeaxanthin epoxidase catalyzes the conversion of zeaxanthin to antheraxanthin and violaxanthin. The Arabidopsis zeaxanthin epoxidase protein sequence was used to query for maize ESTs with sequence similarity. Oligonucleotide primers were designed to amplify a ~500 bp sequence of the ZmZep gene containing exonic and intronic sequence. Two paralogs were amplified; (ZmZep1a and ZmZep1b) exhibiting 82% DNA sequence identity. RT-PCR was performed on mRNA isolated from 7-day shoot and 14-day maize leaf tissue. The amplified product was cloned and sequenced. ZmZep1b is expressed in these tissues and confirmed predicted intron/exon boundaries from database analyses. Genomic sequences were obtained from seven North American inbred lines, and five open-pollinated landraces from New Mexico and Mexico, respectively. Sequence diversity was assessed for these loci. ZmZep1a exhibited highest diversity among the Pueblo lines, while ZmZep1b exhibited highest diversity among open-pollinated Mexican landraces.
Keywords: Zeaxanthin, epoxidase, ZmZep1a, ZmZep1b, RT-PCR, exonic, intronic, Mexican
Topic(s):Biology
Presentation Type: Poster
Session: 60-61
Location: OP Lobby and Atrium
Time: 4:15