SCOL Project: Coevolution of RNA and Peptides — Connecting the Activation Processes
The observation that amino acids are easily available in abiotic environments suggests that RNA coevolved with peptides in an RNA world. In other words, the carriers of information may have coexisted with short polymers of amino acids built by chemical pathways predating the translation of nucleic acid sequences into proteins. This possibility makes the subsequent transition to an RNA-protein world logical.
Ziwei Liu’s work is aimed at precisely identifying chemical pathways potentially responsible for the connection of peptide and RNA chemistries. The present-day biosynthesis of peptides, through elongation of peptide chains by the stepwise addition of activated amino acids in the ribosome, was probably preceded by simpler chemical processes involving activated amino acid building blocks and adducts with short RNA strands.
Beginning with previous work in his advisor’s lab, which showed that intermediates made of amino acid and nucleotide moieties can be easily formed, Liu will work to enlarge the scope of the process to the formation of peptide chains connected to simple nucleotides.
He will study the chemical and kinetic properties of these activated intermediates for their role in the elongations of both peptides and nucleotides. He will also study the stereochemistry of the reactions as a potential process leading to mirror symmetry breaking.
These investigations are part of an ongoing research program based on the physicochemical view that self-organization in the emergence of life process requires both a far-from-equilibrium state and the replication of chemical entities. Introducing free energy through activated amino acid monomers or activated peptides as a means to drive the replication of an information support and the selection of the more efficient sequences may thus be considered an essential step in the evolutionary process leading to life.
Education: State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Ph.D. Inorganic Chemistry
Institution: University Montpellier, Institut des Biomolécules Max Mousseron (laboratory of Robert Pascal)