Abstract Detail

Genetics Section

Wickett, Norman J. [1], Honaas, Loren A [1], Wafula, Eric K [1], Timko, Michael P [2], Yoder, John [3], Westwood, James [4], dePamphilis, Claude W. [5].

Exploring the causes and consequences of parasitism through stage specific transcriptome sequencing in the parasitic plant family Orobanchaceae.

Parasitic plants range in their nutritional dependence on their host from facultative, photosynthetic hemiparasites, through obligate hemiparasites, to non-photosynthetic, obligate holoparasites. Only one plant family, Orobanchaceae, comprises members of all three nutritional types. For this reason, Orobanchaceae is an ideal framework to study the molecular causes and consequences of the parasitic life history. As part of the Parasitic Plant Genome Project, we have sequenced stage specific cDNAs for multiple life history stages from three species of Orobanchaceae (Triphysaria versicolor, Striga hermonthica, and Orobanche aegyptiaca), representing three differing levels of host dependence. Twelve developmental stages for each species were targeted for sequencing and, currently, greater than 3 million 454 ESTs and 400 million paired-end Illumina ESTs have been sequenced. Initial assemblies of these data find between 43,361 and 50,899 unigenes of greater than 200bp in length. Putative unigene annotations were determined using a blastx search against ten fully sequenced plant genomes to assign each unigene to a scaffold of Tribes and Ortho groups (putative gene-families and clusters of orthologous genes, respectively) created for the PlantTribes database. Current assemblies and annotations place unigenes in 6124 to 6914 Tribes and 8946 to 10,056 Ortho groups. Here, we discuss the putative identities of sequenced transcripts with an emphasis on evolution of the photosynthetic apparatus and the development of a parasitic plant specific organ, the haustorium. Transcriptome data is also used here to investigate the role of genome duplication in the evolution of these parasites.

Broader Impacts:

1 - Penn State University, Biology, 403 Life Sciences Bldg, University Park, PA, 16802, USA
2 - University of Virginia, Biology, Gilmer Hall 044, PO Box 400328, Charlottesville, VA, 22904, USA
3 - University of California-Davis, Plant Sciences, Davis, CA, 95616, USA
4 - Virginia Tech, Plant Pathology, Physiology and Weed Science, 410 Price Hall, Blacksburg, Virginia, 24061, USA
5 - Pennsylvania State University, Department of Biology, Institute of Molecular Evolutionary Genetics, and The Huck Institutes of the Life Sciences, University Park, Pennsylvania, 16802, USA

Keywords:
parasitic plants
transcriptome
Solexa sequencing technology
454 sequencing
EST.

Presentation Type: Oral Paper:Papers for Sections
Session: 1
Location: 556A/Convention Center
Date: Monday, August 2nd, 2010
Time: 8:45 AM
Number: 1004
Abstract ID:714