Recently, Prof. Quan Wang，Dr. Junxin Xue and Dr. Wei Jiang in Shanghai Veterinary Research Institute of CAAS and Prof. Kehe Huang from Nanjing Agricultural University, found that thioredoxin reductase (TR) is able to resist oxidative damage from host macrophages and can be considered a crucial virulence factor of Toxoplasma gondii infection. The study was published on line in FASEB Journal (impact factor 5.498) in July 7, 2017.
Thioredoxin reductase (TR) can help pathogens resist oxidative-burst injury from host immune cells by maintaining thioredoxin-reduction state under condition of NADPH consumption. TR is a necessary virulence factor for enabling the persistent infection of some parasites. Here, we performed bioinformatics analyses and biochemical assays to characterize the activity, subcellular localization, and genetic ablation of Toxoplasma gondii TR (TgTR) to shed light on its biological function. Thioredoxin reductase gene of T. gondii was also knock out by CRISPR/CAS9 gene editing technology. and we observed that parasite antioxidant capacity, invasion efficiency, and proliferation were decreased in TR-knockout strains in vitro. Furthermore, our in vivo results revealed that the survival time of mice infected with the TR-knockout strain was significantly prolonged relative to that of mice infected with the wild-type strain. These results suggested that TgTR plays an important role in resistance to oxidative damage and can be considered a virulence factor associated with T. gondii infection.

Interlinkage: http://www.fasebj.org/content/early/2017/07/05/fj.201700008R.