Nucleoprotein (influenza virus A)
| Influenza virus A nucleoprotein | ||
|---|---|---|
|
||
| according to PDB 3ZDP | ||
| Mass / length primary structure | 498 amino acids , 56 kDa | |
| Secondary to quaternary structure | monomeric / multimer | |
| Identifier | ||
| External IDs | ||
The nucleoprotein (synonym nucleoprotein , NP) of the influenza virus is a protein that binds the viral RNA .
properties
The nucleoprotein, as part of the ribonucleoprotein, is a structural protein in influenza virus virions . The ribonucleoprotein consists of the nucleoprotein NP, the viral RNA segments and the proteins of the polymerase complex (PA, PB1 and PB2, with A for acidic or B for basic , depending on their isoelectric points ) necessary for replication and transcription . NP has 498 amino acids , a mass of about 56 kilodaltons and is encoded by the viral genomic segment 5 (ribonuclein bases 46 to 1542 from 1565).
In a virion, NP connects the viral RNA with the matrix protein 1 (M1). Although NP can form oligomers , it can only bind the viral RNA as a monomer . When the endosome is acidified after the endocytosis of influenza viruses, the binding of the M1 to the NP is released, which exposes the nuclear localization signals of the NP (as part of the uncoating process).
The nucleoprotein NP binds to the viral RNA and, after the release of the matrix protein M1, mediates the transport into the cell nucleus via the importin pathway via its two now exposed nuclear localization signals . NP uses Exportin to discharge newly formed viral RNA from the cell nucleus via nuclear pores or NXF1 for a subsequent viral protein synthesis and the formation of new virions.
literature
- DM Knipe, Peter M. Howley (Ed.): Fields Virology . 4th edition, Philadelphia 2001, ISBN 0-7817-6060-7 .
Individual evidence
- ↑ MR Hilleman : Realities and enigmas of human viral influenza: pathogenesis, epidemiology and control. In: Vaccine Vol. 20, 2002, No. 25-26, pp. 3068-87, PMID 12163258 .
- ↑ S. Chenavas, T. Crépin, B. Delmas, RW Ruigrok, A. Slama-Schwok: Influenza virus nucleoprotein: structure, RNA binding, oligomerization and antiviral drug target. In: Future microbiology. Volume 8, number 12, December 2013, ISSN 1746-0921 , pp. 1537-1545, doi : 10.2217 / fmb.13.128 , PMID 24266354 .
- ↑ K. Martin, Ari Helenius : Transport of incoming Influenza Virus Nucleocapsids into the Nucleus. In: J. Virol. 1991, Vol. 56, No. 1, p. 232, PMID 1985199 .
- ↑ EC Hutchinson, E. Fodor: Transport of the influenza virus genome from nucleus to nucleus. In: Viruses. Volume 5, number 10, October 2013, ISSN 1999-4915 , pp. 2424-2446, doi : 10.3390 / v5102424 , PMID 24104053 , PMC 3814596 (free full text).
- ^ A. York, E. Fodor: Biogenesis, assembly, and export of viral messenger ribonucleoproteins in the influenza A virus infected cell. In: RNA biology. Volume 10, number 8, August 2013, ISSN 1555-8584 , pp. 1274-1282, doi : 10.4161 / rna.25356 , PMID 23807439 , PMC 3817148 (free full text).