Proteomics is the large-scale study of proteins.
- The human genome encodes ~23,000 different proteins, which are molecules that carry out the majority of biological functions.
- The proteome provides 1000-fold more cellular information than the genome: there are ~23,000 human genes, ~100,000 transcripts and over 20 million protein variants.
- Because of transcriptional and translational levels of cellular control, not every gene is transcribed, and not every RNA is translated. Conversely, stable proteins often outlive transcripts from which they were made.
- The identity and function of a protein is defined by its unique sequence of amino acids connected through peptide bonds. Most human diseases involve changes in the composition or functions of proteins in one form or another.
- Proteomes are inherently more complex and dynamic than genomes, because each gene can potentially give rise to more than one protein. Adding to this complexity, the abundance of each protein is regulated, and proteins typically become chemically processed and modified, and often engage in complex interactions with other proteins or small molecules (e.g. metabolites, lipids, metal ions and co-factors).
- Proteomics is a powerful technique that allows the identification and quantification of its proteome, on a large-scale, through which researchers can gain important insights into the molecular makeup and physiology of a biological sample.
- Mass spectrometry (MS) is an essential part of the cell biologist’s proteomics toolkit, allowing analyses at molecular and system-wide scales.
- Importantly, proteins are preferred targets for therapeutic agents and diagnostic tests, with proteomics providing insights into the composition, functions, drug interactions, and regulation of proteins which are not predictable based on genome sequences.
Here at the Molecular Proteomics laboratory, our investigators use proteomics to understand the expression, interactions, and signalling of proteins in normal physiology, cancer biology and heart disease models to understand disease mechanisms.
Importantly, proteomics provides important insights into our understanding of cell signalling — specifically the quantitative identification of protein cargo and biological insights of extracellular vesicles (including exosomes) — key intercellular communicators affecting gene expression and phenotype in target cells.