Genomics / Proteomics
Bunnell, Cristy , Dutton, Ashley , Kuehl, Jennifer V. , Boore, Jeffrey L. , Raubeson, Linda A. .
Chloroplast genomes of cycads.
We are in the process of completing three cycad chloroplast genome sequences (Cycas micronesica, Zamia integrifolia, and Dioon edule). A plastid genome sequence has recently been published for Cycas taitungensis (Wu et al 2007, Mol Biol Evol). The published genome is described as having a conventional gene order and organization. We find that not all cycad genomes share that morphology. In addition, our results regarding the tufA-like sequence in cycads and Ginkgo differ somewhat from those described by Wu et al. Both our Cycas and the published genome have lost trnT-GGU, but otherwise, our findings, along with the published work, suggest that cycad chloroplast genomes represent the ancestral seed plant condition in terms of gene content and, perhaps, organization. The genomes have an unusually low number of short dispersed repeats. However they have an above average number (and maximum length) of microsatellite repeats (or SSRs, simple sequence repeats). The genomes exhibit low rates of sequence evolution. For example, the Dioon and Zamia genomes show an overall nucleotide similarity of over 94%. So far we have completed only general comparisons; more detailed analyses are planned.
Log in to add this item to your schedule
1 - Central Washington University, Department of Biological Sciences, 400 E University Way, Ellensburg, WA, 98926-7537, USA
2 - DOE Joint Genome Institute, Department of Evolutionary Genomics, 2800 Mitchell Drive, Walnut Creek, California, 94598, USA
Presentation Type: Poster:Posters for Topics
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM