The research interests of the Liu Lab are in functional proteomics and biopharmaceuticals. Currently we are working on the following projects: (1). Using systems biology approaches to decipher the signaling pathways mediated by disease-related proteases such as caspases and granzymes and by post-translationally modified histones. We address these problems by performing functional protein selections using mRNA-displayed proteome libraries from human, mouse, Drosophila, and C. elegans. (2). Developing novel protein therapeutics and nucleic acid therapeutics that can be used in tumor diagnosis, treatment, and nanomedicine. We use various amplification-based molecular evolution approaches such as mRNA-display and in vivo SELEX to develop novel single domain antibody mimics on the basis of very stable protein domains or to generate aptamers on the basis of nuclease-resistant nucleic acids, that bind to important biomarkers on the surface of cancer cells. We further conjugate these biomarker-binding affinity reagents to small molecule drugs or nanoparticles for targeted delivery of therapeutic agents. (3). Identifying the protein targets of drugs or drug candidates whose action mechanisms are unknown. We combine molecular proteomic and chemical biology approaches to identify the protein targets of drugs whose target-binding affinities are modest.