animals Article Characterization and Functional Importance of Two Glycoside Hydrolase Family 16 Genes from the Rice White Tip Nematode Aphelenchoides besseyi Hui Feng , Dongmei Zhou, Paul Daly , Xiaoyu Wang and Lihui Wei * Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, 210014 Nanjing, China;
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[email protected] Simple Summary: The rice white tip nematode Aphelenchoides besseyi is a plant parasite but can also feed on fungi if this alternative nutrient source is available. Glucans are a major nutrient source found in fungi, and β-linked glucans from fungi can be hydrolyzed by β-glucanases from the glycoside hydrolase family 16 (GH16). The GH16 family is abundant in A. besseyi, but their functions have not been well studied, prompting the analysis of two GH16 members (AbGH16-1 and AbGH16-2). AbGH16-1 and AbGH16-2 are most similar to GH16s from fungi and probably originated from fungi via a horizontal gene transfer event. These two genes are important for feeding on fungi: transcript levels increased when cultured with the fungus Botrytis cinerea, and the purified AbGH16-1 and AbGH16-2 proteins inhibited the growth of B. cinerea. When AbGH16-1 and AbGH16-2 expression A. besseyi was silenced, the reproduction ability of was reduced. These findings have proved for the first time that GH16s contribute to the feeding and reproduction of A. besseyi, which thus provides Citation: Feng, H.; Zhou, D.; Daly, P.; novel insights into how plant-parasitic nematodes can obtain nutrition from sources other than their Wang, X.; Wei, L.