Suppression of PmRab11 inhibits YHV infection in Penaeus monodon

Abstract

Yellow head virus (YHV) is one of the most serious pathogens that causes worldwide shrimp production loss. It enters the cells via clathrin-mediated endocytosis and utilizes small GTPase Rab proteins such as PmRab5 and PmRab7 for intracellular trafficking. In this study, molecular cloning and functional analysis of Rab11 during YHV infection were investigated. PmRab11 cDNA was cloned by Rapid amplification of cDNA ends (RACEs). It contained two forms of sizes 1200 and 1050 bp distinct at the 5' UTR. The coding region of PmRab11 was 645 bp, encoding 214 amino acids. It also demonstrated the characteristics of Rab11 proteins containing five GTP-binding domains, five Rab family domains, four Rab subfamily domains and a prenylation site at the C-terminus. Suppression of PmRab11 using dsRNA-PmRab11 either before or after YHV-challenge resulted in significant inhibition of YHV levels in the hemocytes and viral release in the supernatant in both mRNA and protein levels. In addition, the silencing effect of PmRab11 in YHV-infected shrimps resulted in a delay in shrimp mortality for at least 2 days. Immunofluorescence study showed co-localization between PmRab11 and YHV at 24-72 h post YHV-challenge. In contrast, the co-localization signals were absence in the PmRab11 knockdown hemocytes and the YHV signals accumulated at the perinuclear region at 24 h post YHV-challenge. Then, accumulation of YHV was hardly observed after 48-72 h. These results suggested that PmRab11 is required for YHV infection in shrimp.

PmAP2-β depletion enhanced activation of the Toll signaling pathway during yellow head virus infection in the black tiger shrimp Penaeus monodon

“…In P. monodon , silencing of early endosome antigen 1 (EEA1) protein ( Pm EEA1), involving in early endosome fusion, caused a delay in shrimp mortality due to YHV infection 35 . Similar results were observed in YHV-challenged shrimp with either Pm Rab7 or Pm Rab11 suppression 6 , 36 . These suggested that endosome trafficking plays an important role during YHV infection.…”

Evaluation of the relationship between the 14-3-3ε protein and LvRab11 in the shrimp Litopenaeus vannamei during WSSV infection

“…Similar results were reported in PmRab11 and PmRab7. Silencing PmRab11 10 , PmRab7 52 , 53 or LvRab7 54 resulted in inhibition of viral replication in shrimp. For instance, the co-localization between PmRab11 and YHV was observed in hemocytes at 24 to 72 h post viral injection, whereas in PmRab11 knockdown hemocytes, a low level of co-localization of PmRab11 and YHV was detected at the perinuclear region at 24–72 h. These results revealed that PmRab11 is required for YHV infection in shrimp cells 10 .…”

“…Silencing PmRab11 10 , PmRab7 52 , 53 or LvRab7 54 resulted in inhibition of viral replication in shrimp. For instance, the co-localization between PmRab11 and YHV was observed in hemocytes at 24 to 72 h post viral injection, whereas in PmRab11 knockdown hemocytes, a low level of co-localization of PmRab11 and YHV was detected at the perinuclear region at 24–72 h. These results revealed that PmRab11 is required for YHV infection in shrimp cells 10 . In addition, silencing of PmRab7 resulted in significant inhibition of WSSV-VP28 mRNA and YHV replication, suggesting that PmRab7 required for WSSV and YHV infection in shrimp cell 52 .…”

“…Moreover, the LvRab11 protein exhibited a prenylation site (CC) at its C-terminus; prenylation is a crucial post-translational modification that enables Rab proteins to associate with and target cell membranes 35 . Based on homology searches in the GenBank database, the LvRab11 protein was highly homologous with Rab11 of other species and had the closest phylogenetic relationship with PmRab11 10 and MrRab11A 9 . Thus, the LvRab11 protein might be closely associated with biological functions in cellular processes in shrimp.…”

“…Rab11-mediated trafficking events were reported to have a role in several aspects of innate immunity 8 , in Macrobrachium rosenbergii , MrRab11A was involved in antibacterial and anti-WSSV innate immunity in prawns 9 . Moreover, in Penaeus monodon , PmRab11 was required for yellow head virus (YHV) infection 10 .…”