Grass Carp Prx 3 Elevates Host Antioxidant Activity and Induces Autophagy to Inhibit Grass Carp Reovirus (GCRV) Replication

Abstract

Peroxiredoxins are a family of antioxidant proteins that protect cells from oxidative damage caused by reactive oxygen species (ROS). Herein, the peroxiredoxin 3 gene from grass carp (Ctenopharyngodon idellus), named CiPrx3, was cloned and analyzed. The full-length cDNA of CiPrx3 is 1068 bp long, with a 753 bp open reading frame (ORF) that contains a thioredoxin-2 domain, two peroxiredoxin signature motifs, and two highly conserved cysteine residues. CiPrx3 was ubiquitously expressed in all the tested tissues, while its expression level was altered significantly after exposure to grass carp reovirus (GCRV) and pathogen-associated molecular patterns (PAMPs). CiPrx3 was localized in the mitochondria of transfected cells and concentrated in the nucleus after poly (I:C) treatment. Transformation of CiPrx3 into Escherichia coli enhanced host resistance to H2O2 and heavy metals. Purified recombinant CiPrx3 proteins could protect DNA against oxidative damage. Overexpression of CiPrx3 in fish cells reduced intracellular ROS, increased cell viability, and decreased cell apoptosis caused by H2O2 stimulation and GCRV infection. Further study indicated that CiPrx3 induced autophagy to inhibit GCRV replication in fish cells. Collectively, these results imply that grass carp Prx3 elevates host antioxidant activity and induces autophagy to inhibit GCRV replication.

Grass Carp Reovirus Induces Formation of Lipid Droplets as Sites for Its Replication and Assembly

“…Grass carp reovirus, which was isolated and identified as subtype I by our laboratory ( 50 ), was used in the study of viral infection. Rabbit polyclonal antibodies against the GCRV nonstructural protein NS80 (anti-NS80) and structural protein VP5 (anti-VP5) were prepared in our laboratory ( 51 ). Mouse anti-double-stranded RNA (J2 clone) antibody was purchased from Nordic-MUbio (Susteren, Netherlands).…”

Structure, function and immune evasion strategies of aquareoviruses, with focus on grass carp reovirus

“…Furthermore, autophagy‐related gene 5 and peroxiredoxin 3 induced autophagy and repressed GCRV replication. Therefore, the function of autophagy in GCRV infection needs further study 128,129 …”

Systematic analysis of Prx genes in the Brachypodium genus and their expression pattern under abiotic constraints

“…Also, a Prx member plays an important role in regulating cotton response to PEG-induced dehydration (Zhang et al 2016). The overexpression of CiPrx3 in fish cells reduced intracellular ROS, increased cell viability, and decreased cell apoptosis caused by H 2 O 2 and GCRV infection (Liang et al 2022). Despite these important functions of Prx during plant response to abiotic stresses, no information is available on the structure, organization, or biological functions of Prx genes in the model organism Brachypodium distachyon.…”