From Proteins to Genes: Molecular Biology of Plant Peroxidases

Allegheny College, Meadville PA

Investigators

Abstract

Biological Sciences (61) A semester-long research project is being developed for the laboratory component of a molecular biology course focused on class III plant peroxidases. It engages students in investigation of gene expression at the protein activity and mRNA levels, utilizes cDNA cloning and sequencing to isolate novel sequences, and uses bioinformatic tools to determine the relationship of the novel sequences to those already present in the NCBI and PeroxiBase databases. Intellectual Merit: Peroxidases represent a diverse set of enzymes found in prokaryotes, plants, and animals. Most peroxidases contain a protoporphyrin IX heme and carry out the reduction of hydrogen peroxide at the expense of oxidation of a variety of organic molecules. Peroxidases have been hypothesized to carry out a variety of physiologically relevant functions within plants, including synthesis of lignin and suberin, production of reactive oxygen species to promote defense against pathogens, regulation of cell growth, regulation of auxin levels, and regulation of hydrogen peroxide levels as a component of signal transduction pathways responding to reactive oxygen species. There is a large body of primary literature related to plant peroxidases in a variety of fields, including biophysics, inorganic chemistry, biochemistry, genetics, plant physiology, agriculture, molecular biology, and genomics, that investigates the structure, function, and ecological relevance of this large super family of proteins. Thus, this is a rich area for development of a semester-long project that allows students to investigate peroxidase expression at the proteomic and mRNA levels. Broader Impacts: An average of 32 undergraduate students per year will be exposed to research that is interdisciplinary and uses technologies, such as real-time PCR and bioinformatics, that are relevant to research in molecular biology. Of the students taking the molecular biology class, typically 60 percent are female and approximately 20 percent of these students matriculate to a Masters or Ph.D. program in the sciences. Of those pursuing a graduate degree, 70 percent are female. As part of this project, the PI and undergraduate collaborators are jointly developing protocols and lab assistance tools and making them available through a Web site, thus providing resources that allow others to use and adapt this model to their teaching laboratories. Outcomes of this project are also being disseminated through submission of novel peroxidase sequences to GenBank and PeroxiBase (a class III peroxidase specific database), a poster presentation at the American Society of Plant Biologists meeting in 2008, and submission of a manuscript to a journal focusing on science education.