The function of snodprot in the cerato-platanin family from Dactylellina cionopaga in nematophagous fungi.

Dactylellina cionopaga is a potential biocontrol agent of phytoparasitic nematodes. Here the functions of snodprot of D. cionopaga were analysed. The gene was transcribed with a higher level under inducing conditions with nematodes. The recombinant protein expressed in Pichia pastoris had a molecular weight of 14 kDa and might form polymers in its native state. In a concentration-dependent manner, snodprot changed the chemotaxis and increased the body-bend frequency of Caenorhabditis elegans, but did not induce immunity in the indicated plants significantly. The results of an immunofluorescence assay proved that snodprot was expressed during the development of traps and conidia. According to the parasitism mechanisms of nematophagous fungi and the chemotaxis and locomotion mechanisms of C. elegans, the possible active sites of snodprot were speculated to be ASE or ASI. The gene identification indicated that snodprot is a novel parasitism-related protein of nematophagous fungi, and possesses novel activity, different from other members of the cerato-platanin family.