TY - JOUR TI - Ancient origins of arthropod moulting pathway components AU - de Oliveira, André Luiz AU - Calcino, Andrew AU - Wanninger, Andreas A2 - VijayRaghavan, K A2 - Martinez, Pedro VL - 8 PY - 2019 DA - 2019/07/03 SP - e46113 C1 - eLife 2019;8:e46113 DO - 10.7554/eLife.46113 UR - https://doi.org/10.7554/eLife.46113 AB - Ecdysis (moulting) is the defining character of Ecdysoza (arthropods, nematodes and related phyla). Despite superficial similarities, the signalling cascade underlying moulting differs between Panarthropoda and the remaining ecdysozoans. Here, we reconstruct the evolution of major components of the ecdysis pathway. Its key elements evolved much earlier than previously thought and are present in non-moulting lophotrochozoans and deuterostomes. Eclosion hormone (EH) and bursicon originated prior to the cnidarian-bilaterian split, whereas ecdysis-triggering hormone (ETH) and crustacean cardioactive peptide (CCAP) evolved in the bilaterian last common ancestor (LCA). Identification of EH, CCAP and bursicon in Onychophora and EH, ETH and CCAP in Tardigrada suggests that the pathway was present in the panarthropod LCA. Trunk, an ancient extracellular signalling molecule and a well-established paralog of the insect peptide prothoracicotropic hormone (PTTH), is present in the non-bilaterian ctenophore Mnemiopsis leidyi. This constitutes the first case of a ctenophore signalling peptide with homology to a neuropeptide. KW - EvoDevo KW - Mollusca KW - mollusk KW - molting JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -