This is a new pilot project to use mass spectrometry methods to determine the multiplicity and character of proteins coming from individual mRNAs.
Many processes contribute to the complexity of gene products that come from one gene.
In addition to alternate splicing and RNA editing that increase mRNA complexity, protein modification and alternative translation can all expand the population of proteins that come from one mRNA species. Although we know a good deal about protein modifications on a protein by protein basis, we know little in a genome-wide sense. We know even less about the frequency of occurrence of unusual translation events. Alternative translations, or recoding, include programmed frameshifts, bypassing of mRNA regions, and redefinition of stop codons to encode one of the twenty amino acids or selenocysteine the 21st amino acid. We are developing technology to ask how many different protein products come from each mRNA species.