Abstract Detail

Macroevolution

Wickell, David Allen [1], Kuo, Li-Yaung [2], Li, Fay-Wei [3].

CAM photosynthesis in the aquatic lycophyte Isoetes taiwanensis.

Crassulacean acid metabolism (CAM) is the process by which certain plants concentrate inorganic carbon at night to fix into sugar during the day. It has evolved multiple times as an adaptation to arid conditions. Interestingly, CAM has also evolved convergently among various aquatic species as a response to low CO2 availability under water. Aquatic species of Isoetes constitute the earliest diverging lineage of plants that perform CAM and as such, represent a powerful model for investigating CAM evolution. This study is an initial investigation into CAM genetics in the species Isoetes taiwanensis. Here we use RNA-seq to profile diel fluctuation in expression of transcripts putatively associated with CAM. Alongside this analysis, recently assembled genomic data allows us to compare differential expression in Isoetes to other (non-aquatic) CAM plants including Kalanchoe fedtschenkoi and Ananas comosus. We hypothesize that like other CAM plants, Isoetes utilizes existing photosynthetic pathways to accomplish CAM via modulated diel expression of a particular set of genes. This convergence may be the product of changes to regulatory elements, protein coding sequences or as seen in other species, some combination of the two.

1 - Cornell University, Plant Biology, 533 Tower Rd., Ithaca, NY, 14853, USA
2 - Institute of Molecular & Cellular Biology, National Tsing Hua Universi, Hsinchu, Taiwan
3 - Cornell University, Boyce Thompson Institute, 533 Tower Rd, Ithaca, NY, 14853, USA

Keywords:
Isoetes
CAM photosynthesis
parallel evolution
RNA-seq.

Presentation Type: Poster
Session: P, Macroevolution Posters
Location: Arizona Ballroom/Starr Pass
Date: Monday, July 29th, 2019
Time: 5:30 PM This poster will be presented at 6:15 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: PMC002
Abstract ID:693
Candidate for Awards:None