The evolution of sexual dimorphism: A sex-specification gene in the dimorphic eyes of a crustacean
Poster Number
20
Format
Poster Presentation
Faculty Mentor Name
Ajna Rivera
Faculty Mentor Department
Biological Sciences
Abstract/Artist Statement
We use Euphilomedes carcharodonta as a model organism to study the evolution of sexual dimorphism. Previous work has shown that E. carchardonta eyes are highly dimorphic and this is most likely due to the different ecological niches males and females inhabit. Our lab has also found a handful of eye-development genes correlated with the dimorphic phenotype. However, this only solves the link between eye development and eye phenotype. It does not solve the link between sex and dimorphic eye development. Specifically, how do the eye fields in embryonic E. carcharodonta “know” whether they are male or female. To begin to answer this question, we plan on examining sexdetermination genes in E. carcharodonta eye development. Our initial analysis found one gene used in male eye development, the zinc-finger domain transcription factor doublesex (dsx). The first step towards this is cloning dsx from E. carcharodonta. In order to clone the gene, we microdissected eyes and extracted RNA. Then we generated cDNA via reverse transcriptase and used dsx-specific primers to isolate the gene and amplify it through the polymerase chain reaction (PCR). We tailed the amplicon and ligated it into a bacterial cloning vector before transforming it into chemically competent cells. We selected colonies, checked for the presence of an inserted amplicon, and grew them overnight in liquid culture. We then mini-preped our plasmids and checked concentration with a Nanodrop and sent off for sequencing. Although we had initial success with PCR and positive colonies, low concentration of plasmid and negative sequencing results showed us that we need to attempt cloning again.
Location
DeRosa University Center, Ballroom
Start Date
30-4-2016 10:00 AM
End Date
30-4-2016 12:00 PM
The evolution of sexual dimorphism: A sex-specification gene in the dimorphic eyes of a crustacean
DeRosa University Center, Ballroom
We use Euphilomedes carcharodonta as a model organism to study the evolution of sexual dimorphism. Previous work has shown that E. carchardonta eyes are highly dimorphic and this is most likely due to the different ecological niches males and females inhabit. Our lab has also found a handful of eye-development genes correlated with the dimorphic phenotype. However, this only solves the link between eye development and eye phenotype. It does not solve the link between sex and dimorphic eye development. Specifically, how do the eye fields in embryonic E. carcharodonta “know” whether they are male or female. To begin to answer this question, we plan on examining sexdetermination genes in E. carcharodonta eye development. Our initial analysis found one gene used in male eye development, the zinc-finger domain transcription factor doublesex (dsx). The first step towards this is cloning dsx from E. carcharodonta. In order to clone the gene, we microdissected eyes and extracted RNA. Then we generated cDNA via reverse transcriptase and used dsx-specific primers to isolate the gene and amplify it through the polymerase chain reaction (PCR). We tailed the amplicon and ligated it into a bacterial cloning vector before transforming it into chemically competent cells. We selected colonies, checked for the presence of an inserted amplicon, and grew them overnight in liquid culture. We then mini-preped our plasmids and checked concentration with a Nanodrop and sent off for sequencing. Although we had initial success with PCR and positive colonies, low concentration of plasmid and negative sequencing results showed us that we need to attempt cloning again.