Ellen E. Hostert
Title: Associate Professor of Biology
Office: Science 123
Office Hours: Click here for PDF
- Bio 111, General Zoology
- Bio 265, Genetics
- Bio 340, Evolution
- Bio 355, Conservation Biology
- Bio 410, Senior Seminar in Biology
Research Interest: I am a population geneticist, so I use the tools of genetics to address questions in evolutionary biology. My research examines genetic variation in natural populationsof animals. My current project examines variation in an immune system gene in Atlantic salmon (Salmo salar). We amplify our gene of interest with the polymerase chain reaction (PCR). We look for alternate forms of the gene (alleles) by running our PCR reactions on gels using the single-stranded conformational polymorphism (SSCP) technique. SSCP gives us a way to "see" alleles that differ by as little as one base. When we find a new allele, we clone it and sequence it.
Here is the official summary of the project if you want more details.
Current Project: Major Histocompatibility Complex Class II Alleles: Genetic and Functional Variation in the Antigen Binding Site of Atlantic Salmon, Salmo salar
1) To assess genetic variation in populations of anadromous and landlocked Atlantic salmon.
2) To assess the type of selection acting on the class IIB locus in Atlantic salmon, and the functional consequences of the allelic diversity observed.
3) To carry out comparisons with other salmonid, teleost, and vertebrate species.
This study will investigate the effect of exposure to different suites of parasites on the functional variation at the Major Histocompatibility Complex (MHC) class IIB locus.
The MHC controls the adaptive immune response in vertebrates. MHC molecules recognize and bind different pathogens depending on the structural match between the MHC and the pathogen. It is generally accepted that individuals with two different forms of the MHC protein will be able to respond to a broader set of pathogens than individuals with only one form. By extension, it is thought that infectious disease outbreaks will be less devastating in populations with greater MHC diversity than in MHC depauperate populations.
The class II MHC genes are associated with resistance to parasites. Knowledge of the allelic diversity within and between populations will be instrumental in the design of population-specific vaccines for all vertebrates, including humans. Most parasitic infections are treated with antiparasitic drugs; however, many species of parasites are evolving resistance to those drugs. The development of vaccines is an alternative to the use of antiparasitic drugs that avoids the evolution of drug resistance. But vaccines can produce uneven protection in vaccinated populations. The variation in vaccine effectiveness is, at least partially, based on the ability of the MHC to bind to the pathogen.
Previous Student Project: Molecular Analysis of Coyotes in Maine: Evidence for Hybridization with Wolves?
Favorite organism: Drosophila melanogaster, the common fruit fly.