Ramsey Research
Our Projects:
Heteroplasmic fitness
The bulk of my PhD research is investigating what (and if) are the fitness consequences related to heteroplasmic (i.e. containing multiple types of mitochondrial DNA). Daucus carota has been found to have heteroplasmic individuals and to paternally leak (which may create heteroplasmy). In animals the effects have generally been found to be negative, but in plants the effects are unknown.
Maternal Transmission
An interesting question is how often is heteroplasmy transmitted from one generation to the next? It should be that the germline bottleneck within individuals limits within individual variation of organellar genomes, but that need not be the case. If it is not the case, then a further question is how does that occur? I'm using my fitness individuals to assess the levels of heteroplasmy in self-pollinated plants.
Evolution of the mt genome
This will be a large bioinformatic component of my dissertation. We're going to whole genome sequence many individuals, run the sequences through a bioinformatic pipeline to determine where in the genome individuals are likely to be heteroplasmic. Then we will be able to assess levels of selection on various regions of the genome. This has a direct impact on evolution of the genome.
Credit: Iorizzo, M., Senalik, D., Szklarczyk, M., Grzebelus, D., Spooner, D., & Simon, P. (2012). De novo assembly of the carrot mitochondrial genome using next generation sequencing of whole genomic DNA provides first evidence of DNA transfer into an angiosperm plastid genome. BMC Plant Biology. BioMed Central Ltd.
Impact of Queen Anne's Lace on native pollination
Queen Anne's Lace is invasive in many parts of the world, but even though it has a large, attractive umbel, no work has been done on how it is affecting native pollination. An undergraduate and I went to Nantucket, Massachusetts to determine if it is having an impact on the native plant, Sericocarpus asteroides.
Crop-wild gene flow
We are investigating levels of gene flow between domesticated carrot and its wild relative, Queen Anne's Lace, which is non-native and generally invasive in many parts of the world.