Divergent Antiviral Mechanisms of Two Viperin Homeologs in a Recurrent Polyploid Fish.

Cheng-Yan Mou,Zhong-Wei Wang,Guang-Xin Wang,Qi-Ya Zhang,Shun Li,Peng Yu,Zhi Li,Xiao-Juan Zhang,Jian-Fang Gui,Long-Feng Lu,Li Zhou,Yang Wang,Jin-Feng Tong

doi:10.3389/fimmu.2021.702971

Abstract

Polyploidy and subsequent diploidization provide genomic opportunities for evolutionary innovations and adaptation. The researches on duplicated gene evolutionary fates in recurrent polyploids have seriously lagged behind that in paleopolyploids with diploidized genomes. Moreover, the antiviral mechanisms of Viperin remain largely unclear in fish. Here, we elaborate the distinct antiviral mechanisms of two viperin homeologs (Cgviperin-A and Cgviperin-B) in auto-allo-hexaploid gibel carp (Carassius gibelio). First, Cgviperin-A and Cgviperin-B showed differential and biased expression patterns in gibel carp adult tissues. Subsequently, using co-immunoprecipitation (Co-IP) screening analysis, both CgViperin-A and CgViperin-B were found to interact with crucian carp (C. auratus) herpesvirus (CaHV) open reading frame 46 right (ORF46R) protein, a negative herpesvirus regulator of host interferon (IFN) production, and to promote the proteasomal degradation of ORF46R via decreasing K63-linked ubiquitination. Additionally, CgViperin-B also mediated ORF46R degradation through autophagosome pathway, which was absent in CgViperin-A. Moreover, we found that the N-terminal α-helix domain was necessary for the localization of CgViperin-A and CgViperin-B at the endoplasmic reticulum (ER), and the C-terminal domain of CgViperin-A and CgViperin-B was indispensable for the interaction with degradation of ORF46R. Therefore, the current findings clarify the divergent antiviral mechanisms of the duplicated viperin homeologs in a recurrent polyploid fish, which will shed light on the evolution of teleost duplicated genes.

Highlights

Genome sequencing explosion has highlighted a profound impact of polyploidy and subsequent post-polyploid diploidization (PPD) on evolutionary innovations and adaptation
Six Cgviperin transcripts were cloned from the head-kidney of gibel carp clone F using rapid amplification of cDNA ends (RACE)-Polymerase Chain Reaction (PCR) (Supplementary Figure S1)
To further illustrate the exact mechanism in this process, we identified that the conversion of Microtubule-associated Protein 1A/1B-Light Chain 3 (LC3)-I to LC3-II was promoted by CgViperin-B, which means that autophagy is enhanced by the overexpression of CgViperin-B (Figure 8C)

Summary

Introduction

Genome sequencing explosion has highlighted a profound impact of polyploidy and subsequent post-polyploid diploidization (PPD) on evolutionary innovations and adaptation. Viperin ( known as Vig in rainbow trout) was first identified as an antiviral protein induced by human cytomegalovirus in 2001 [14, 15]. It belongs to the radical Sadenosylmethionine (SAM) enzyme family [14, 16, 17] and is composed of three distinct domains [18]. The C-terminal domain is highly conserved, but its role remains poorly defined [24]. This domain has been proposed to be involved in protein–protein interactions [19]

Methods

Results

Conclusion