RT Journal Article
SR Electronic
T1 Evidence supporting an antimicrobial origin of targeting peptides to endosymbiotic organelles
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.03.04.974964
DO 10.1101/2020.03.04.974964
A1 Clotilde Garrido
A1 Oliver D. Caspari
A1 Yves Choquet
A1 Francis-André Wollman
A1 Ingrid Lafontaine
YR 2020
UL http://biorxiv.org/content/early/2020/06/21/2020.03.04.974964.abstract
AB Mitochondria and chloroplasts emerged from primary endosymbiosis. Most proteins of the endosymbiont were subsequently expressed in the nucleo-cytosol of the host and organelle-targeted via the acquisition of N-terminal presequences, whose evolutionary origin remains enigmatic. Using a quantitative assessment of their physico-chemical properties, we show that organelle targeting peptides, which are distinct from signal peptides targeting other subcellular compartments, group with a subset of antimicrobial peptides. We demonstrate that extant antimicrobial peptides target a fluorescent reporter to either the mitochondria or the chloroplast in the green alga Chlamydomonas reinhardtii and, conversely, that extant targeting peptides still display antimicrobial activity. Thus, we provide strong computational and functional evidence for an evolutionary link between organelle-targeting and antimicrobial peptides. Our results support the view that resistance of bacterial progenitors of organelles to the attack of host antimicrobial peptides has been instrumental in eukaryogenesis and in emergence of photosynthetic eukaryotes.Competing Interest StatementThe authors have declared no competing interest.