Research

Research in the Martinez lab is focused on the discovery and characterization of a newly uncovered class of small proteins. Advances in genomics, proteomics, and bioinformatics have revealed that the human genome encodes vastly more proteins than the roughly 20,000 included in public databases, with perhaps an additional 10-20,000 more than previously believed. This dark proteome is predominantly encoded by small open reading frames (smORFs), which contain less than 100 codons and for decades were assumed to be randomly occurring and non-functional. The protein products of these translated smORFs have been dubbed microproteins. Microproteins were previously overlooked, because their small size and often lower abundance relative to larger canonical proteins make them difficult to detect. We tackled this problem by developing an integrated platform combining ribosome profiling (Ribo-seq), de novo transcriptome assembly, mass spectrometry, and bioinformatics to rigorously identify novel microprotein-coding smORFs throughout the human genome.

The discovery of microproteins raises new questions about what their roles and functions are in both normal physiology and disease. Currently, our group’s primary goal is to discover microproteins that mediate the hallmarks of cancer in hopes of identifying new therapeutic targets and biomarkers. We are also exploring their roles in metabolism and aging through collaborations.