Document Type
Honors Project
Publication Date
6-10-2026
Abstract
Chronic hepatitis B virus (HBV) infection afflicts approximately 296 million people worldwide and causes nearly 900,000 deaths annually from liver cirrhosis and hepatocellular carcinoma. Current nucleos(t)ide analog therapies suppress viral replication but rarely achieve functional cure due to persistence of covalently closed circular DNA (cccDNA) in infected hepatocytes. The viral protein HBx maintains cccDNA transcriptional activity by recruiting the host DDB1–CUL4 E3 ubiquitin ligase complex to degrade the Smc5/6 restriction factor. Disrupting the HBx–DDB1 protein–protein interaction silences cccDNA transcription and represents a rational path toward functional cure orthogonal to existing therapies.
This study establishes an engineered yeast two-hybrid (Y2H) platform to guide structure-based inhibitor design. A single-plasmid Y2H architecture using Golden Gate assembly enables scarless, directional cloning of interacting protein pairs. Transformation into Saccharomyces cerevisiae PJ694a confirmed HBx–DDB1 interaction. Future directions include constructing pSB36 (wild-type HBx) and pSB37 (nonbinding HBx control) to map critical interface residues. This platform provides the engineering infrastructure to identify optimal sites for competitive inhibitor design, positioning HBx–DDB1 disruption as the transcriptional-silencing arm of rational combination therapies aimed at functional HBV cure.
Level of Honors
cum laude
Department
Biology
Advisor
Kimberly Dickson
Recommended Citation
Khan, Vivian, "Using Yeast to Investigate a Promising Therapeutic Target for Hepatitis B" (2026). Lawrence University Honors Projects. 225.
https://lux.lawrence.edu/luhp/225