Biotechnology Commons^™

Ai-Powered Multi-Omics Integration For Predictive Modeling Of Genotype-Environment-Phenotype Relationships, You Wu

Dissertations, Theses, and Capstone Projects

This dissertation presents a series of machine learning frameworks for modeling genotype–environment–phenotype relationships through integrative predictive modeling of multi-omics data. The work addresses three major axes of biological complexity: modeling biological information transmission cross-levels from genes to proteins to phenotypes, predicting molecular features cross-scale from cells to tissues to organisms, and translating phenotypes cross-species from model systems to humans. Each proposed method also tackles key machine learning (ML) challenges in the biomedical domain, including data scarcity, domain shift, out-of-distribution (OOD) generalization, and hierarchical modeling. Specifically, this dissertation introduces five novel deep learning algorithms: MultiDCP predicts drug-induced transcriptomic and viability responses …

Development Of Collagen Mimetic Mini-Fibrils With Tunable Collagenase Susceptibility, Jui Chaugule

Dissertations, Theses, and Capstone Projects

Collagen fibrils are the primary molecular scaffold of all connective tissues and provide the essential support for cell migration and differentiation. Collagen fibrils represent one of the most complex molecular hierarchies: three polypeptide chains in Gly-Xaa-Yaa repeating amino acid sequences, first form the rod-shaped collagen triple helix. These triple helices further self-assemble laterally in a specific manner to form fibrils having the characteristic 67 nm axially repeating structure known as the D-period. Enzymatic digestion of collagen fibrils by matrix metalloproteinases (MMPs) is critical for several physiological processes and is of particular consequence during wound healing. Many of the mechanisms of …

Mechanistic And Engineering Studies Of Lov Photoreceptors In Yeast, Matthew M. Cleere

Dissertations, Theses, and Capstone Projects

A variety of cellular biosensors have evolved which can translate electromagnetic radiation from the environment into biological functions. Light-Oxygen-Voltage (LOV) domains in particular, are a group of photoreceptors that respond to blue wavelengths of light and can become a cellular photoswitch by converting this stimulus through their attached effector domains. For instance, the Helix-Turn-Helix (HTH) DNA-binding activity of the bacterial transcription factor EL222 and the Regulator of G-protein Signaling (RGS) in the fungal membrane associating protein BcLOV4 are both induced by blue-light sensing LOV domains. While previous work has provided the field with a structural characterization of LOV proteins in …

Engineered Plga Nanofibers For Drug Delivery, Andrew Mancuso

Dissertations, Theses, and Capstone Projects

Poly-lactic-co-glycolic acid (PLGA) polymers are rapidly gaining momentum as a platform for next-generation drug delivery systems due to their ease and low cost of synthesis, favorable biocompatibility and biodegradability, and lack of toxicity. In particular, the application of drug-loaded PLGA nanofibers directly to a target tissue may represent a promising alternative to traditional routes of drug administration (e.g., oral, injectable) as they offer the potential to greatly improve bioavailability, increase efficacy, and reduce off-target toxicity. Furthermore, the use of such a system may potentially allow for greater flexibility in clinical drug development, by enabling the use of compounds which have …

Leveraging Bio-Inspired Molecules For Cancer Theranostics, Douglas S. Macpherson

Dissertations, Theses, and Capstone Projects

A variety of molecules can be radiolabeled and delivered to a cancer site for the purposes of diagnostics and therapy. Among the most promising of tumor targeting molecules are peptides and antibodies. These bio-inspired molecules can be designed and synthesized to target and respond to cancer cells based on the properties of those cells. Matrix metalloproteinase (MMP) enzymes are over-expressed by some metastatic cancers, in which they are responsible for the degradation and remodeling of the extracellular matrix. In recent years, MMPs have emerged as promising targets for enzyme-responsive diagnostic probes because oligopeptides can be designed to be selectively hydrolyzed …

Development Of Optical Nanomaterial For Enhanced Cerenkov Imaging, Qize Zhang

Dissertations, Theses, and Capstone Projects

Cancer is a significant public health problem worldwide and is the second leading cause of death in the United States. Imaging has increasingly been used over the last two decades to improve the diagnosis and guidance of tumor tissue removal surgery. Among the most widely used techniques for in vivo imaging are planar and tomographic fluorescence imaging and bioluminescence imaging. Despite their utility, these techniques are primarily restricted to preclinical use. Factors that have prevented translation from the bench to the bedside include depth-penetration considerations, regulatory issues, and toxicity. A recent development in nuclear imaging has been the ability to …

Tools And Strategies For The Patterning Of Bioactive Molecules And Macromolecules, Daniel J. Valles

Dissertations, Theses, and Capstone Projects

Hypersurface Photolithography (HP) is a printing method for fabricating structures and patterns composed of soft materials bound to solid surfaces and with ~1 micrometer resolution in the x, y, and z dimensions. This platform leverages benign, low intensity light to perform photochemical surface reactions with spatial and temporal control of irradiation, and, as a result, is particularly useful for patterning delicate organic and biological material. In particular, surface- initiated controlled radical polymerizations can be leveraged to create arbitrary polymer and block- copolymer brush patterns. Chapter 1 will review the advances in instrumentation architectures from our group that have made these …

Water-Responsive, Peptide-Based Crystals, Roxana Piotrowska

Dissertations, Theses, and Capstone Projects

Water-responsive (WR) materials  that exert significant forces in response to changing hydration levels are receiving growing interest due to their potential applications, including use as actuators for energy harvesting devices, artificial muscles, and soft robotics. Reported examples include biological and synthetic materials with abilities to efficiently convert the chemical potential of water into mechanical actuations. However, these systems are typically complex, and consequently, their WR mechanisms are not well-understood thus preventing rational design and optimization. This thesis demonstrates the design and development of WR peptide crystals that mimic and enhance understanding of natural WR systems. The peptide crystals, with intrinsic …

Hur Ubiquitination By Brca1/Bard1 And Its Role In Controlling Gene Expression During Dna Damage Response, Gamage M. Aruggoda

Dissertations, Theses, and Capstone Projects

Despite our understanding of the biochemistry of the BRCA1/BARD1 E3 ligase, we know very little of the mechanism by which its cellular substrates, how they are chosen, how its E3 Ub ligase activity is regulated, which are the cofactors involved in this regulation, and how the substrates are modified during DDR. In this dissertation, I further evaluate BRCA1/BARD1-mediated E3 ligase activity and how CstF-50 and p97 regulate this reaction working as cofactors. My data show that BRCA1/BARD1 is an E3 ligase that ubiquitinates the RNA binding protein Human antigen R(HuR).

HuR is abundant in the nucleus and is transported to …

Developing A Dissociative Nanocontainer For Peptide Drug Delivery, Michael Patrick Kelly

Dissertations, Theses, and Capstone Projects

The potency and specificity of bioactive peptides have propelled these agents to the forefront of pharmacological research. However, delivery of peptides to their molecular target in cells is a major obstacle to their widespread application. A Trojan Horse strategy of packaging a bioactive peptide within a modified protein cage to protect it during transport, and releasing it at the target site, is a promising delivery method. Recent work has demonstrated that the viral capsid of the P22 bacteriophage can be loaded with an arbitrary, genetically-encoded peptide, and externally decorated with a cell-penetrating peptide, such as HIV-Tat, to translocate across in …

Eugenics In The 21st Century, Jessica Linn Chin

Dissertations, Theses, and Capstone Projects

Eugenics is the science of enhancing the human population through the management of breeding and hereditary traits. This thesis explores the history of eugenics and shows how eugenic practices continue in the 21^st century with advancements in technology and positive eugenic goals that can result in adverse effects on the human body and society. When Sir Francis Galton coined the term eugenics in 1883, he intended to improve British society with the use of positive eugenics. Galton used positive eugenics to encourage people with good mental and physical qualities to produce more children. He avoided negative eugenics, which involved …

Renal Specific Rnai Delivery By Fibrillar Nanoparticle Excipients, Sam Wong

Dissertations, Theses, and Capstone Projects

RNA interference (RNAi) is a powerful tool to manipulate the phenotype of an organism by silencing the expression of specific genes and is viewed as a highly promising platform for treating undruggable targets and disorders where small molecule drugs and antibodies would fail. However, development of RNAi based therapies has faced major barriers including cellular and tissue-specific uptake of the Small Interfering RNA (siRNA). Utilizing different nanoparticles as RNAi excipients, cellular uptake and gene silencing potency can be greatly improved. The research in Dr. McDevitt groups has fibrillar carbon nanotubes (CNT) as carriers for siRNA for gene silencing in vitro …

Design And Application Of Matrix Metalloproteinase-9-Responsive Peptide Nanostructures, Jiye Son

Dissertations, Theses, and Capstone Projects

Matrix metalloproteinase (MMP)-responsive materials have been investigated since the late 1990’s as scaffolds for tissue engineering and since then, have evolved into sophisticated nanomaterials for cancer-targeting therapy. In this thesis titled, “Design and Application of Matrix Metalloproteinase-9-Responsive Peptide Nanostructures,” we aim to answer the following key questions: can MMP-responsive nanomaterials improve the efficacy of anti-cancer treatments? How can we achieve specificity towards MMPs using nanomaterials? Finally, what are the advantages in using peptides as building blocks to create MMP-responsive nanostructures? Each chapter in the thesis will address one or more of the key questions and draw conclusions at the end.

Identification And Characterization Of Barrier Insulator Activity In The T-Cell Receptor Alpha Locus Control Region, Gayathri Devi Raghupathy

Dissertations, Theses, and Capstone Projects

Genes of different spatiotemporal expression profiles are often juxtaposed in the genome. This organization raises risks of cross-regulatory influences from neighboring genes; for instance heterochromatin can spread over euchromatin or long-range acting enhancers can inappropriately activate genes. Gene regulatory elements such as Locus Control Regions (LCR) and Insulators prevent such cross-communications and allow for normal gene expression patterns. In transgenic systems, LCRs limit influences from surrounding chromatin by providing site-of-integration independent and specific spatiotemporal expression upon a linked transgene. The field’s understanding of the ability of an LCR to overcome chromatin influences and allow site-of-integration independent expression is minimal. Interestingly, …

Pretargeted Radioimmunotherapy Utilizing The Inverse Electron Demand Diels-Alder Reaction, Rosemery Membreno

Dissertations, Theses, and Capstone Projects

Radioimmunotherapy capitalizes on the specificity and affinity of antibodies for their antigens to localize radioactivity at the tumor site. One limitation in using antibodies is their long circulation time, which can take days to weeks to fully clear from blood circulation. When a radioisotope is directly conjugated to this immunoglobulin vector, the red marrow and other healthy organs are receiving a constant radiation dose while it is in blood circulation. This not only harms healthy organs, but limits the dose of radioactivity that can be administered thus prolonging treatment. A promising alternative to limit the radiation dose to non-tumor tissue …

Supercharged Models Of Intrinsically Disordered Proteins And Their Utility In Sensing, Peter J. Schnatz

Dissertations, Theses, and Capstone Projects

In this thesis I show that greatly increasing the magnitude of a protein’s net charge using surface supercharging transforms that protein into a ligand-gated or counterion-gated conformational molecular switch. To demonstrate this I first modified the designed helical bundle hemoprotein H4 using simple molecular modeling, creating a highly charged protein which both unfolds reversibly at low ionic strength and undergoes the ligand-induced folding transition commonly observed in signal transduction by intrinsically disordered proteins in biology. Due to the high surface charge density, ligand binding to this protein is allosterically activated by low concentrations of divalent cations and the polyamine spermine. …

Mutagenesis Of Human Alpha-Galactosidase A For The Treatment Of Fabry Disease, Erin Stokes

Dissertations, Theses, and Capstone Projects

Fabry disease is an X-linked lysosomal storage disorder caused by the deficiency of the enzyme, α-galactosidase A, which results in the accumulation of the lipid substrate. This accumulation results in obstruction of blood flow in patients and early demise at approximately 40-60 years of age. There is currently only one FDA approved treatment (Fabrazyme) classified as an enzyme replacement therapy. However, approximately 88% of patients experience a severe immune response that, rarely, can be fatal and is a huge cost burden at average $250,000 a year per patient. The structure of α-galactosidase A has been previously determined to be a …