Biology Department Seminar

Currently available techniques of mass spectrometry (MS)-based proteomics are still lack of sufficient sensitivity, accuracy, and throughput to investigate the integrity of a biological process. In the past years, we have been focusing on developing various unbiased and discovery-directed quantitative proteomic approaches to address the biological concerns involved in signal transduction and cellular regulation. These technology are primarily based on a strategy of metabolic cell labeling or amino acid-coded mass tagging that provides ‘in-spectra’ quantitative markers for both protein identification and quantitation. As results we are able to perform de novo peptide sequencing to resolve the ambiguity in identifying low-abundance proteins and post-translational modifications. With our newly introduced technology of ‘dual-tagging’ quantitative proteomic approach, we have conducted a pathway-scale study of signal protein interactions involved in TLR-mediated innate immunity in immune cells. Our systems-scale analyses led to simultaneous identification of a group of novel signaling proteins as new regulators of NF-kB activation mediated by TLR4. This result strongly suggests a new molecular basis for selective regulation of TLR pathway by certain undiscovered proteins.
Also I will discuss some latest technology developments made in my lab aiming at improving the sensitivity and sequence coverage in signal molecule analysis.