Identification of immune inducible genes from the velvet worm Epiperipatus biolleyi (Onychophora)

SummaryOnychophora are the next relatives of Arthropoda and, hence, represent an important taxon to unravel relationships among Insecta, Crustacea, Arachnida, and Myriapoda. Here, we screened for immune inducible genes from the onychophoran Epiperipatus biolleyi (Peripatidae) by injecting crude bacterial LPS and applying the suppression subtractive hybridization technique. Our analysis of 288 cDNAs resulted in identification of 36 novel genes in E. biolleyi whose potential homologues from other animals are known to mediate immune-related signaling (e.g. mitogen-activated protein kinase kinase 1 and immunoglobulin enhancer binding protein), to be involved in cellular processes (e.g. perilipin and myosin light chain), or to act as immune effector molecules (e.g. lysosomal β-galactosidase, a putative antimicrobial peptide and a potential thiolester containing protein). Comparisons with homologous genes from other animals including the two most favored ecdysozoan model organisms of innate immunity research, the nematode Caenorhabditis elegans and the fruit fly Drosophila melanogaster, provide further insights into the origin and evolution of Arthropoda immunity.