Abstract Detail

Genomics / Proteomics

Ross, T. Gregory [1], Barrett, Craig [2], Henriquez , Claudia L [3], Cuenca, Argelia [4], Les , Donald H [5], DAVIS , JERROLD I [6], Peterson, Gitte [4], Stevenson, Dennis [7], Graham, Sean W. [1].

Molecular evolution and phylogenetics of the monocot order Alismatales using whole plastid genomes.

The transitions of some land plants back to an aquatic ecosystem represent fascinating examples of a major evolutionary transition. The monocot order Alismatales provides the most successful example of this transition, as members of this large and cosmopolitan clade occupy a diverse range of aquatic habitats, and include the only reversions to marine habitats, the seagrasses. Although much progress has been made in understanding the higher-order phylogenetic structure of the order, multiple uncertainties still persist, including the nature of the deepest split in the order, and the monophyly-status of several families. To address this we recovered and characterized plastid genes sets (~79 protein-coding genes and 4 rDNA genes per taxon) using genome-survey sequencing and de novo assembly. We also completed full plastid circles for a subset of plastid genomes by bridging contig gaps using PCR and Sanger sequencing. We sequenced representatives for most (~90%) of the 58 genera that belong to Tofieldiaceae and 12 “core alismatid” families. Our phylogenetic analyses also included a representative sampling of Araceae lineages from a recently published study on that family. In addition to reconstructing a well supported plastid-based backbone of the order, we characterized the repeated loss of plastome genes for NADH dehydrogenase, a plastid enzyme complex that has been implicated in chlororespiration and in mitigating photo-oxidative stress. The loss of this complex is rare in photosynthetic plants, but our data imply that there were three to four independent losses in submerged lineages in the order.

1 - University of British Columbia, Botany, 3529 - 6270 University Boulevard, Vancouver, BC, V6T 1Z4, Canada
2 - California State University, Los Angeles, Biological Sciences, 5151 State University Drive, Los Angeles, CA, 90032-8201, USA
3 - Washington University in St. Louis, Evolution, Ecology & Population Biology, One Brookings Drive, Campus Box 1137, St. Louis, MO, 63130, USA
4 - Natural History Museum of Denmark, University of Copenhagen, Sølvgade 83, opg. S 1307 , Copenhagen, Denmark
5 - University Of Connecticut, Department Of Ecology & Evolutionary Biology, 75 N. Eagleville Road, Unit 3043, Storrs, CT, 06269-3043, USA
6 - CORNELL UNIVERSITY, PLANT BIOLOGY AND L.H. BAILEY HORTORIUM, 412 MANN LIBRARY BUILDING, ITHACA, NY, 14853-4301, USA
7 - THE NY BOTANICAL GARDEN, 2900 SOUTHERN BLVD, BRONX, NY, 10458-5126, USA

Keywords:
plastid genome
Gene loss
aquatic plants
monocots
Alismatales.

Presentation Type: Oral Paper:Papers for Topics
Session: 35
Location: Pines South/Boise Centre
Date: Wednesday, July 30th, 2014
Time: 9:30 AM
Number: 35007
Abstract ID:744
Candidate for Awards:None