In this dissertation I study evolutionary patterns at genes encoding antimicrobial peptides (AMPs) in frogs. AMPs are short, amphipathic, cationic, secreted proteins that kill bacteria and other pathogens through a non-catalytic mechanism that involves
binding to and disrupting the microbial cell membrane. In many animal taxa, positive selection is much...
Whole-genome duplications are radical evolutionary events that have driven speciation and adaptation in many taxa. Higher-order
polyploids have complex histories often including interspecific hybridization and dynamic genomic changes. This chromosomal
reshuffling is poorly understood for most polyploid species, despite their evolutionary and agricultural importance, due to the
challenge of distinguishing...
Whole-genome duplications are radical evolutionary events that have driven speciation and adaptation in many taxa. Higher-order
polyploids have complex histories often including interspecific hybridization and dynamic genomic changes. This chromosomal
reshuffling is poorly understood for most polyploid species, despite their evolutionary and agricultural importance, due to the
challenge of distinguishing...
Full Text:
Strawberry
Subgenomes Revealed by Dense Targeted Capture Linkage Maps
Tennessen, J. A., Govindarajulu, R
Whole-genome duplications are radical evolutionary events that have driven speciation and adaptation in many taxa. Higher-order
polyploids have complex histories often including interspecific hybridization and dynamic genomic changes. This chromosomal
reshuffling is poorly understood for most polyploid species, despite their evolutionary and agricultural importance, due to the
challenge of distinguishing...
Gynodioecy is a sexual system wherein females coexist with hermaphrodites. It is of interest
not only because male-sterile plants are advantageous in plant breeding but also because it can be a crucial
step in the evolutionary transition to entirely separate sexes (dioecy) from a hermaphroditic ancestor. The
gynodioecious diploid wild...
Motivation: The goal of any parentage analysis is to identify as many parent-offspring relationships as possible, while minimizing incorrect assignments. Existing methods can achieve these ends, but require additional information in the form of demographic data, thousands of markers, and/or estimates of genotyping error rates. For many non-model systems, it...
Whitebark pine (Pinus albicaulis) inhabits an expansive range in western North America, and it is a keystone species of subalpine environments. Whitebark is susceptible to multiple threats – climate change, white pine blister rust, mountain pine beetle, and fire exclusion – and it is suffering significant mortality range-wide, prompting the...
Gynodioecy, the coexistence of females and hermaphrodites, occurs in 20% of angiosperm families and often enables transitions between hermaphroditism and dioecy. Clarifying mechanisms of sex determination in gynodioecious species can thus illuminate sexual system evolution. Genetic determination of gynodioecy, however, can be complex and is not fully characterized in any...
Schistosomiasis, a neglected global pandemic, may be curtailed by blocking transmission of the parasite via its intermediate hosts, aquatic snails. Elucidating the genetic basis of snail-schistosome interaction is a key to this strategy. Here we map a natural parasite-resistance polymorphism from a Caribbean population of the snail Biomphalaria glabrata. In...
Background:
New strategies to combat the global scourge of schistosomiasis may be revealed by increased understanding of the mechanisms by which the obligate snail host can resist the schistosome parasite. However, few molecular markers linked to resistance have been identified and characterized in snails.
Methodology/Principal Findings:
Here we test six...
