SYVN1 and parasitic infectious disease: However, to date, there has been no report on the ERAD-associated E3 ubiquitin-protein ligase HRD1 of Plasmodium. Our study showed that PfHRD1 is more expressed in middle schizonts than in the other five erythrocytic stages, and that PfHRD1 specific antibodies can significantly reduce parasitemia by more than half in vitro (100 μg/mL, 5.95% ± 0.08% vs. 2.82% ± 0.45%; p = 0.0003).