3.2 | Development-related genes for key enzymes, ion
channels, receptors and secretome
To understand the genetic basis for the adaptation ofB. schroederi to the
parasitic life, we assessed the abundance of several major protein
classes in B. schroederi , A. suum , P. univalens ,
and T. canis (Table S10 and Fig. S12b). A genome-wide search
enabled us to identify 62 G-protein coupled receptors (GPCRs), 437
proteases and protease inhibitors (Supplementary Data 2c). Some
chemoreceptor families, especially those differentially expressed during
the life cycle, were almost completely conserved among nematodes. For
example, the homologues of Caenorhabditis elegans daf-37(GeneID: Baysch11898) and daf-38 (GeneID: Baysch06944), which are
known to mediate ascaroside signaling, are expressed during the
transition from dauer larvae to infective larvae (Park et al., 2012). By
comparing with the ligand-gated ion channel gene set collected from
wormBase, 65 genes were identified, including members of the previously
described nematode acetylcholine receptor classes (deg-3 ,acr-16 , unc-29 and unc-38 ) (A. Coghlan et al.,
2018). We predicted excretory/secretory proteins (EPs) of B.
schroederi , and at least 1,395 EPs (5.26% of total protein) with
diverse functions were identified, including 1,046 conventionally
secreted proteins and 349 nonconventionally secreted proteins
(Supplementary Data 2d-e).