Heterodera schachtii glutathione peroxidase (HsGPx) is a parasitism protein

The beet cyst nematode ( Heterodera schachtii ) is a specialized obligate biotroph that is considered a major threat to sugar beet production. After infection, H. schachtii induce massive physiological and molecular changes to plant cells and create sophisticated syncytial feeding sites. Nematode secretions called effectors govern all of these changes. Here, we identify one of these effectors, H. schachtii glutathione peroxidase (HsGPx), and provide evidence that HsGPx is involved in parasitism. In situ hybridization showed that HsGPx is specifically localized within esophageal glands of pre-parasitic second-stage juveniles (J2). We also showed that HsGPx is upregulated in the post-parasitic stages. Knocking down HsGPx in nematodes by host-induced gene silencing hampers nematode development and leads to smaller nematode size and smaller associated feeding sites in Arabidopsis. Therefore, HsGPx plays an important role in the interaction between the nematode and plant.