tetano
Editor, Senior Moderator
J Virol. 2012 Feb 15. [Epub ahead of print]
Identification and Characterization of three novel nuclear export signals in influenza A virus nucleoprotein.
Yu M, Liu X, Cao S, Zhao Z, Zhang K, Xie Q, Chen C, Gao S, Bi Y, Sun L, Ye X, Gao GF, Liu W.
Source
From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
Abstract
The nuclear export of the influenza A virus ribonucleoprotein (vRNP) is crucial for virus replication. As a major component of the vRNP, nucleoprotein (NP) alone can also be shuttled out of the nucleus by interacting with chromosome region maintenance 1 (CRM1) and, therefore, is hypothesized to promote the nuclear export of the vRNP. In the present study, three novel nuclear export signals (NESs) of the NP protein, named NES1, NES2 and NES3, were identified as being responsible for mediating its nuclear export. The nuclear export of NES3 was CRM1-dependent, while that of NES1 or NES2 was CRM1-independent. Inactivation of these NESs led to overall nuclear accumulation of the NP protein. Mutation of all three NP-NESs significantly impaired viral replication. Based on structures of influenza virus NP oligomers, these three hydrophobic NESs are found present on the surface of oligomeric NPs. Functional studies indicated that oligomerization is also required for nuclear export of NP. Together, these results suggest that the nuclear export of NP is important for virus replication and relies on its NESs and oligomerization.
PMID:
22345439
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22345439
Identification and Characterization of three novel nuclear export signals in influenza A virus nucleoprotein.
Yu M, Liu X, Cao S, Zhao Z, Zhang K, Xie Q, Chen C, Gao S, Bi Y, Sun L, Ye X, Gao GF, Liu W.
Source
From the CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
Abstract
The nuclear export of the influenza A virus ribonucleoprotein (vRNP) is crucial for virus replication. As a major component of the vRNP, nucleoprotein (NP) alone can also be shuttled out of the nucleus by interacting with chromosome region maintenance 1 (CRM1) and, therefore, is hypothesized to promote the nuclear export of the vRNP. In the present study, three novel nuclear export signals (NESs) of the NP protein, named NES1, NES2 and NES3, were identified as being responsible for mediating its nuclear export. The nuclear export of NES3 was CRM1-dependent, while that of NES1 or NES2 was CRM1-independent. Inactivation of these NESs led to overall nuclear accumulation of the NP protein. Mutation of all three NP-NESs significantly impaired viral replication. Based on structures of influenza virus NP oligomers, these three hydrophobic NESs are found present on the surface of oligomeric NPs. Functional studies indicated that oligomerization is also required for nuclear export of NP. Together, these results suggest that the nuclear export of NP is important for virus replication and relies on its NESs and oligomerization.
PMID:
22345439
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/22345439