Scientists at UCL have discovered a novel role played by ribosomes during the folding of new proteins in cells, described in their paper in Nature . Ribosomes, the cell's dedicated molecular machines for protein synthesis, make all proteins in life and do so by piecing together one amino acid building block at a time. As they are being synthesised, these nascent proteins simultaneously attempt to fold while still associated to their parent ribosome, referred to as co-translational protein folding.
Understanding how exactly protein folding occurs remains a key challenge for scientists, and this co-translational folding provides the way in which cells ensure the safe and efficient production and assembly of new proteins in their functional native states. Failure to fold or aberrant folding is associated with a plethora of devastating diseases. As most of the understanding of protein folding has arisen from lab experiments with isolated polypeptides in bulk solution (not specifically on the ribosome), it has proven difficult to reconcile findings on the ribosome (which is a more typically realistic experimental setting) that show considerable differences in folding to those seen from isolated refolding studies.
In the new paper, scientists have revealed that ribosomes are even more important to the folding process than previously believed, as they direct folding pathways by impacting the energy and stability of the new peptide chains. By experimentally capturing and imaging snap.