Mona Mehdy

Microalgae are highly efficient photosynthetic organisms. Besides their central ecological roles, they are also increasingly valued for nutritional and specialty chemicals, use for bioplastics and biofuels.   Major losses due to diverse grazers have prompted investigations of microalgae defense mechanisms.  Damaged cells of a model diatom species release oxylipins which promote survival of nearby responding cells in regions of high herbivore activity. A major project in my lab is to understand molecular mechanisms used by microalgae to resist herbivores. Our study using the marine model diatom Phaeodactylum tricornutum demonstrated rapid membrane lipid composition and permeability changes. These findings were supportive of the hypothesis that membrane remodeling is a key element in the development of cellular resistance to herbivory. Current research is focused on signaling responses which maintain high photosynthetic efficiency and viability.   Based on transcriptome, mRNA turnover and transcription analyses, functional analyses of a light harvesting complex gene candidate through CRISPR disruption lines are underway to understand its role in contributing to adaptive responses to herbivory.  A second project concerns extracellular matrix protein effects on stress hormone signaling in higher plants.