Biomolecular Sciences Student Research Presentations

Paige Skinner, Ph.D. Candidate

Bending Without Breaking: Transcriptomic Plasticity in Sagebrush

The intensifying threat of climate change is creating novel and increasingly severe environmental conditions threatening plant survival and ecosystem sustainability. Phenotypic plasticity has emerged as a critical mechanism enabling plants to respond to rapid environmental shifts through flexible changes in physiology and gene expression (i.e., transcriptomic plasticity) without requiring physical DNA alterations. Sagebrush (Artemisia tridentata; Sunflower family), a keystone species of the sagebrush steppe, underpins ecosystem stability and supports hundreds of dependent species, yet it remains vulnerable to intensifying drought and heat stressors. Here, I present the first experimental evidence of transcriptomic plasticity in genetically identical sagebrush individuals (i.e., plantlets) subjected to combined drought and heat stress to portray landscape conditions. To further characterize transcriptomic plasticity, drought and heat shock treatments were also applied. This plasticity resulted in the activation of protein degradation responses, a shift in metabolism to conserve energy and repurpose biomolecules, and slowed growth, revealing dynamic molecular responses to changing environmental conditions. To identify key regulatory candidates controlling abiotic stress responses and phenotypic plasticity, I used an integration of bioinformatic tools to investigate the high mobility group B (HMGB) chromatin-remodeling protein family. This pipeline allows the rapid prediction of key genes in climate adaptation to streamline in vitro analyses. To expand to a larger view of the landscape, I am currently developing new reference lines to evaluate transcriptional responses under combined drought and heat stress. This includes twenty representative individual lines sourced from ten populations across the sagebrush steppe. Together, these chapters advance our understanding of plasticity in plants to identify candidate genotypes and regulatory mechanisms important for resilience. This research can inform restoration strategies aimed at maintaining ecosystem survival in a rapidly warming and drying west.

Committee:
Dr. Sven Bureki, Department of Biological Sciences

Dr. Eric Hayden, Department of Biological Sciences

Dr. Matthew Ferguson, Department of Physics

Dr. Jennifer Forbey. Department of Biological Science

David Oke, Ph.D. Candidate

Notch Signaling Through the Lens of Biomolecular Condensate

Although biomolecular condensates have been known to exist in cells for almost one hundred years, only recently did the broad importance of biomolecular condensates come to be understood. It is believed that some condensates form on specific genetic loci and accumulate a population of transcription factors and co-factors to drive transcription. Notch proteins are cell-cell communication proteins that play critical roles in the development of all animals through their transcriptional activities. In this seminar, I will share new insights revealing how biomolecular condensation may underlie previously unrecognized mechanisms of Notch signaling. By viewing this canonical pathway through the modern framework of phase separation, we uncover a new dimension of Notch biology.

Committee:
Dr. Allan Albig, Department of Biological Sciences

Dr. Brad Morrison, Department of Biological Sciences

Dr. Cheryl Jorcyk, Department of Biological Sciences

Dr. Daniel Fologea, Department of Physics