BIOTECHNOLOGY TRAINING PROGRAM

Doctoral Research Project:  Hydrogels are an impressive subset of biomaterials in that they can possess a myriad of compositions that enable various material functions. Some of these hydrogels are designed to respond to different types of stimuli, such as light, pH, temperature, etc., which are called “smart” hydrogels. However, these “smart” hydrogels are typically designed to respond to a limited number of standard environmental signals and require a substantial amount of stimuli to respond. To circumvent this issue and design a biologically responsive hydrogel, the objective of my research project is to design a cell-free bioprogrammable material that can respond to specific biochemical cues via artificial cells (aCells) embedded within the hydrogel matrix. These aCells are synthetic vesicles that contain a cell-free protein system (CFPS) and are able to overcome the limitations living cells present. By coupling the design of the hydrogel with CFPS, this allows for the synthesis of a new class of materials that possess integrated signal processing that provides signal-dependent mechanical property changes. This novel material will be able to overcome the recurring challenges of live cells by separating cell survival, growth, shape, etc., from the design of the hydrogel. 

Doctoral Research Project:  In contrast to many organelles that can be made de novo, the biogenesis of mitochondria can only occur from pre-existing mitochondria. Because of this, the faithful partitioning of mitochondria is crucial for the fitness and longevity of newborn cells. Many studies have shown that in cell divisions resulting in two cells with distinct fates, there is an asymmetric partitioning of mitochondria, with one cell inheriting “fitter” mitochondria. Despite the overwhelming evidence suggesting the idea of “inheritance of the fittest”, the specific mechanism that governs the asymmetric segregation of mitochondria, as well as the cellular changes that occur after inheritance is disrupted, are still unclear. The first goal of my project is to test the hypothesis that a mitochondria fitness marker exists on the outer membrane, allowing for the asymmetric inheritance of mitochondria. To test this hypothesis, I will screen cardiolipin and mitochondrial outer membrane protein import machinery mutants, examining asymmetry in mitochondrial function by utilizing different biosensors. My second goal is to address how aging is affected when the quantity and/or quality of mitochondria inherited by a newborn cell deviates significantly from wild-type cells. Since previous study has shown that altering the amount of mitochondria inherited by daughter cells impacts cellular aging, I will test the hypothesis that there is a threshold of “fit” mitochondria that must be inherited to maintain cellular homeostasis. I will use a series of mutants to increase or decrease the amount of mitochondria inherited and implement Cell- ACDC to identify and separate cells at different cell cycle stages with varying mitochondrial volumes. 

Doctoral Research Project:  The first step to effective treatment is the timely and accurate diagnosis of patients. Numerous indications progress rapidly and are terminal if not diagnosed early. Several therapeutics are only effective in the presence of a specific biomarker. Delayed diagnosis for bacterial or viral infections increases population mortality rates. While reliable diagnostic methods for nucleic acids have been established, protein detection remains a challenge in biosensor development for the point of care. My project focuses on the engineering, characterization and optimization of split enzyme protein circuits that can enhance the sensitivity, modularity and accessibility of diagnostic biosensors.

Doctoral Research Project:  Virus-like particles (VLPs) are structures derived from viruses but lack the ability to replicate. They possess a variety of characteristics that are beneficial for targeted drug delivery, including the ability to disassemble and spontaneously reassemble around a negatively charged cargo of interest, such as a cytotoxic drug. The known landscape of VLPs allows for ligands that bind to receptors found overexpressed on cancer cells to be conjugated to the exterior surface of the VLP.  However, to utilize VLPs as a viable targeted drug delivery system, we must be able to understand how we can modify and optimize them in order to improve their efficiency. I study the formation of a chimeric capsid of the MS2 VLP, which consists of different mutants of MS2 reassembled together. The chimeric capsid will allow for control of ligand quantity presented on the surface of MS2, and it will generate capsids with increased uptake and enhanced properties for drug delivery.

Doctoral Research Project:  A promising, emerging therapeutic technology is “living pharmacies,” in which mammalian cells are genetically engineered and then implanted into a patient to produce biological therapeutics in situ. A key challenge is developing strategies for controlling the production of such therapeutics; to address that goal, my project focuses on developing genetic circuits that make in situ production controllable, safe, and effective. Our work focuses on enabling in situ production of a promising class of drugs called glucagon-like peptide-1 receptor agonists (GLP-1 RAs). Treatment of type 2 diabetes and obesity with GLP-1 RAs is promising, but treating by injection of a recombinant drug is expensive and availability can be limited by supply shortages, leading to health disparities or poor outcomes. My project focuses on developing a living pharmacy to address these challenges. I aim to design an electrically inducible gene circuit that, when implemented in a cell, drives production of GLP-1 RAs on-demand while employing synthetic biology control technology to enhance productivity, durability, viability, and safety. Our hope is that this technology will validate a general strategy for producing biological therapeutics on-demand, with durable and tunable production, to improve the treatment of many diseases.