TY - JOUR
T1 - A cypovirus VP5 displays the RNA chaperone-like activity that destabilizes RNA helices and accelerates strand annealing
AU - Yang, Jie
AU - Cheng, Zhenyun
AU - Zhang, Songliu
AU - Xiong, Wei
AU - Xia, Hongjie
AU - Qiu, Yang
AU - Wang, Zhaowei
AU - Wu, Feige
AU - Qin, Cheng Feng
AU - Yin, Lei
AU - Hu, Yuanyang
AU - Zhou, Xi
N1 - Funding Information:
This work was supported by National Basic Research Program of China [973 Program, 2014CB542603]; the National Natural Science Foundation of China [31270190 to X.Z., 81201292 to X.Z. and 31270189 to Y.H.]; the Fundamental Research Funds for the Central Universities [204274391 to J.Y.]; the Chinese 111 Project [B06018]. Funding for open access charge: Wuhan University
PY - 2014/2
Y1 - 2014/2
N2 - For double-stranded RNA (dsRNA) viruses in the family Reoviridae, their inner capsids function as the machinery for viral RNA (vRNA) replication. Unlike other multishelled reoviruses, cypovirus has a single-layered capsid, thereby representing a simplified model for studying vRNA replication of reoviruses. VP5 is one of the three major cypovirus capsid proteins and functions as a clamp protein to stabilize cypovirus capsid. Here, we expressed VP5 from type 5 Helicoverpa armigera cypovirus (HaCPV-5) in a eukaryotic system and determined that this VP5 possesses RNA chaperone-like activity, which destabilizes RNA helices and accelerates strand annealing independent of ATP. Our further characterization of VP5 revealed that its helix-destabilizing activity is RNA specific, lacks directionality and could be inhibited by divalent ions, such as Mg2+, Mn2+, Ca2+ or Zn2+, to varying degrees. Furthermore, we found that HaCPV-5 VP5 facilitates the replication initiation of an alternative polymerase (i.e. reverse transcriptase) through a panhandle-structured RNA template, which mimics the 5′-3′ cyclization of cypoviral positive-stranded RNA. Given that the replication of negative-stranded vRNA on the positive-stranded vRNA template necessitates the dissociation of the 5′-3′ panhandle, the RNA chaperone activity of VP5 may play a direct role in the initiation of reoviral dsRNA synthesis.
AB - For double-stranded RNA (dsRNA) viruses in the family Reoviridae, their inner capsids function as the machinery for viral RNA (vRNA) replication. Unlike other multishelled reoviruses, cypovirus has a single-layered capsid, thereby representing a simplified model for studying vRNA replication of reoviruses. VP5 is one of the three major cypovirus capsid proteins and functions as a clamp protein to stabilize cypovirus capsid. Here, we expressed VP5 from type 5 Helicoverpa armigera cypovirus (HaCPV-5) in a eukaryotic system and determined that this VP5 possesses RNA chaperone-like activity, which destabilizes RNA helices and accelerates strand annealing independent of ATP. Our further characterization of VP5 revealed that its helix-destabilizing activity is RNA specific, lacks directionality and could be inhibited by divalent ions, such as Mg2+, Mn2+, Ca2+ or Zn2+, to varying degrees. Furthermore, we found that HaCPV-5 VP5 facilitates the replication initiation of an alternative polymerase (i.e. reverse transcriptase) through a panhandle-structured RNA template, which mimics the 5′-3′ cyclization of cypoviral positive-stranded RNA. Given that the replication of negative-stranded vRNA on the positive-stranded vRNA template necessitates the dissociation of the 5′-3′ panhandle, the RNA chaperone activity of VP5 may play a direct role in the initiation of reoviral dsRNA synthesis.
UR - https://www.scopus.com/pages/publications/84895813112
UR - https://www.scopus.com/pages/publications/84895813112#tab=citedBy
U2 - 10.1093/nar/gkt1256
DO - 10.1093/nar/gkt1256
M3 - Article
C2 - 24319147
AN - SCOPUS:84895813112
SN - 0305-1048
VL - 42
SP - 2538
EP - 2554
JO - Nucleic acids research
JF - Nucleic acids research
IS - 4
ER -