Abstract Detail

Comparative Genomics/Transcriptomics

Field , Richard D [1], Heyduk, Karolina [2], Leebens-Mack, Jim [3].

In search of the regulatory basis of crassulacean acid metabolism (CAM): a comparative genomics approach in three species of Yucca L.

Carbon concentration mechanisms (CCMs) are strategies used by plants to concentrate leaf carbon levels and increase photosynthetic and water-use efficiency (WUE). In crassulacean acid metabolism (CAM), carbon acquisition is confined to nighttime phases when temperatures, and thus transpiration, are lower than in the daytime. Though physiologically well characterized, a complete understanding of circadian CAM gene regulation is still lacking. Using three species from the genus Yucca L., we take a comparative genomics approach to uncover the evolutionary means by which plants repurpose conserved house-keeping genes into temporally-expressed carbon fixation genes. To this end, we combine information about chromatin accessibility, histone post-translational modifications, and gene expression, collected from 24-hour time course experiments, to construct CAM gene transcriptional networks. Our model system is ideal for comparative analyses because the three species differ in their use of CAM: Y. aloifolia does strong CAM, Y. filamentosa does not use a CCM, and Y. gloriosa, a hybrid of the other two species, switches to facultative weak CAM under drought stress. Previously phylogenetic analyses support Y. filamentosa as being representative of the ancestral type of carbon acquisition; thus, we will use our model to further elucidate both the regulatory requirements for CAM gene expression and the evolutionary trajectory by which plants tie CAM genes into the circadian clock.

1 - University of Georgia, Genetics, 120 W Green St, Athens, GA, 30602, USA
2 - Yale University, Department of Ecology and Evolutionary Biology, 165 Prospect Street, New Haven, CT, 06520, United States
3 - University Of Georgia, Plant Biology, 2101 Miller Plant Sciences, Athens, GA, 30602, United States

Gene Expression
Chromatin Structure.

Presentation Type: Poster This poster will be presented at 5:30 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PGT019
Abstract ID:980
Candidate for Awards:Genetics Section Poster Award

Copyright © 2000-2019, Botanical Society of America. All rights reserved