title: The neuropeptide complement of the marine annelid Platynereis dumerilii.
abstract: BACKGROUND
  The marine annelid Platynereis dumerilii is emerging as a powerful lophotrochozoan experimental model for evolutionary developmental biology (evo-devo) and neurobiology. Recent studies revealed the presence of conserved neuropeptidergic signaling in Platynereis, including vasotocin/neurophysin, myoinhibitory peptide and opioid peptidergic systems. Despite these advances, comprehensive peptidome resources have yet to be reported.
  
  
  RESULTS
  The present work describes the neuropeptidome of Platynereis. We established a large transcriptome resource, consisting of stage-specific next-generation sequencing datasets and 77,419 expressed sequence tags. Using this information and a combination of bioinformatic searches and mass spectrometry analyses, we increased the known proneuropeptide (pNP) complement of Platynereis to 98. Based on sequence homology to metazoan pNPs, Platynereis pNPs were grouped into ancient eumetazoan, bilaterian, protostome, lophotrochozoan, and annelid families, and pNPs only found in Platynereis. Compared to the planarian Schmidtea mediterranea, the only other lophotrochozoan with a large-scale pNP resource, Platynereis has a remarkably full complement of conserved pNPs, with 53 pNPs belonging to ancient eumetazoan or bilaterian families. Our comprehensive search strategy, combined with analyses of sequence conservation, also allowed us to define several novel lophotrochozoan and annelid pNP families. The stage-specific transcriptome datasets also allowed us to map changes in pNP expression throughout the Platynereis life cycle.
  
  
  CONCLUSIONS
  The large repertoire of conserved pNPs in Platynereis highlights the usefulness of annelids in comparative neuroendocrinology. This work establishes a reference dataset for comparative peptidomics in lophotrochozoans and provides the basis for future studies of Platynereis peptidergic signaling.
authors.affiliation: Max Planck Institute for Developmental Biology, Spemannstrasse 35, 72076, Tübingen, Germany. markus.conzelmann@tuebingen.mpg.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Conzelmann
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Williams
authors.forename: Karsten
authors.initials: K
authors.lastname: Krug
authors.forename: Mirita
authors.initials: M
authors.lastname: Franz-Wachtel
authors.forename: Boris
authors.initials: B
authors.lastname: Macek
authors.forename: Gáspár
authors.initials: G
authors.lastname: Jékely
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000845:Annelida / Q000235:genetics*; D005075:Biological Evolution; D019295:Computational Biology; D008018:Life Cycle Stages / Q000235:genetics; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009479:Neuropeptides / Q000235:genetics*; D020543:Proteome / Q000378:metabolism; D059467:Transcriptome
chemical_list: D009479:Neuropeptides; D020543:Proteome