A team of scientists led by Manuel Rodríguez-Concepción, a CSIC researcher at the Centre for Research in Agricultural Genomics (CRAG), has shown that under normal conditions chloroplasts get rid of these defective proteins by degrading them using the molecular machinery called protease Clp. However, when the accumulation of aggregated proteins exceeds the ability of the Clp protease to remove them, the chloroplasts generate a distress signal that travels to the nucleus of the cell to activate the production of repair proteins, called chaperones. The chaperones, in turn, are transported to the chloroplasts to undo the protein "lumps" and unfold the disaggregated proteins, favoring that they can be folded back correctly and recover their function in a few hours. These molecular mechanisms are similar to those that work in our nerve cells when misfolded proteins are produced in the mitochondria.