Virologica Sinica

, 26:245 | Cite as

Putative phosphorylation sites on WCA domain of HA2 is essential for Helicoverpa armigera single nucleopolyhedrovirus replication

  • Yi-pin Lv
  • Qian Wang
  • Chun-chen Wu
  • Rong-juan Pei
  • Yuan Zhou
  • Yun WangEmail author
  • Xin-wen Chen


Protein phosphorylation is one of the most common post-translational modification processes that play an essential role in regulating protein functionality. The Helicoverpa armigera single nucleopolyhedrovirus (HearNPV) orf2-encoded nucleocapsid protein HA2 participates in orchestration of virus-induced actin polymerization through its WCA domain, in which phosphorylation status are supposed to be critical in respect to actin polymerization. In the present study, two putative phosphorylation sites (232Thr and 250Ser) and a highly conserved Serine (245Ser) on the WCA domain of HA2 were mutated, and their phenotypes were characterized by reintroducing the mutated HA2 into the HearNPV genome. Viral infectivity assays demonstrated that only the recombinant HearNPV bearing HA2 mutation at 245Ser can produce infectious virions, both 232Thr and 250Ser mutations were lethal to the virus. However, actin polymerization assay demonstrated that all the three viruses bearing HA2 mutations were still capable of initiating actin polymerization in the host nucleus, which indicated the putative phosphorylation sites on HA2 may contribute to HearNPV replication through another unidentified pathway.

Key words

Helicoverpa armigera single nucleopolyhedrovirus (HearNPV) Actin polymerization Protein phosphorylation N-WASP 


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Copyright information

© Wuhan Institute of Virology, CAS and Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Yi-pin Lv
    • 1
    • 2
  • Qian Wang
    • 2
  • Chun-chen Wu
    • 1
  • Rong-juan Pei
    • 1
  • Yuan Zhou
    • 1
  • Yun Wang
    • 1
    Email author
  • Xin-wen Chen
    • 1
  1. 1.Key Laboratory of Agricultural and Enviromental Microbiology, Wuhan Institute of VirologyChinese Academy of SciencesWuhanChina
  2. 2.Graduate University of the Chinese Academy of SciencesBeijingChina

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