Variation of Human Transfer RNA Demand and Supply

Abstract

Codons function as translation units in open-reading-frames (ORF) of genes to encode for proteins. Transfer RNAs (tRNAs) mediate the connection of every codon to its cognate amino acid. Despite the cooperation between messenger and transfer RNA during translation, approaches to integrate codon usage and tRNA quantities remain to be established. Using matched mRNA- and tRNA-sequencing of peripheral blood cells, we apply a precision-biology approach quantitatively integrating transcriptomic codon- and corresponding tRNA-abundance. Thereby, we classify codons as highly or lowly supplied and compare optimality of synonymous codons. Additionally, we describe substantial differences regarding the conservation of a codons tRNA-supply among healthy donors. A meta-ORF-analysis demonstrates depletion of lowly supplied codons at translation start sites. Discrepancy between codon- and tRNA-abundance, and codon-preference depending on the distance to the translation start site, seem to be non-random and could affect translational speed and thus provide a novel level of regulation of protein abundance.