P26078 (NCAP_I42A0) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Nucleoprotein

Alternative name(s):
Nucleocapsid protein
Short name=Protein N

Gene names

Name:

NP

Organism

Influenza A virus (strain A/Swine/Jamesburg/1942 H1N1)

Taxonomic identifier

383538 [NCBI]

Taxonomic lineage

Viruses › ssRNA viruses › ssRNA negative-strand viruses › Orthomyxoviridae › Influenzavirus A › Influenza A virus › H1N1 subtype

Virus host

Aves [TaxID: 8782]
Homo sapiens (Human) [TaxID: 9606]
Sus scrofa (Pig) [TaxID: 9823]

Protein attributes

Sequence length	498 AA.
Sequence status	Complete.
Protein existence	Inferred from homology

General annotation (Comments)

Function	Encapsidates the negative strand viral RNA, protecting it from nucleases. The encapsidated genomic RNA is termed the ribonucleoprotein (RNP) and serves as template for transcription and replication. The RNP needs to be localized in the nucleus to start an infectious cycle, but is too large to diffuse through the nuclear pore complex. NP comprises at least 2 nuclear localization signals and is responsible of the active RNP import into the nucleus through the cellular importin alpha/beta pathway. Later in the infection, nucleus export of RNP are mediated through viral proteins NEP interacting with M1 which binds nucleoproteins. It is possible that the nucleoprotein binds directly exportin-1 (XPO1) and plays an active role in RNP nuclear export. M1 interaction with RNP seems to hide nucleoprotein's nuclear localization signals. Soon after a virion infects a new cell, M1 dissociates from the RNP under acidification of the virion driven by M2 protein. Dissociation of M1 from RNP unmask nucleoprotein's nuclear localization signals, targeting the RNP to the nucleus By similarity.
Subunit structure	Homomultimerizes to form the nucleocapsid. May bind human exportin-1. Binds to viral genomic RNA. Protein-RNA contacts are mediated by a combination of electrostatic interactions between positively charged residues and the phosphate backbone and planar interactions between aromatic side chains and bases By similarity.
Subcellular location	Virion Potential. Host nucleus.
Post-translational modification	Late in virus-infected cells, may be cleaved from a 56-kDa protein to a 53-kDa protein by a cellular caspase. This cleavage might be a marker for the onset of apoptosis in infected cells or have a specific function in virus host interaction By similarity.
Sequence similarities	Belongs to the influenza viruses nucleoprotein family.

Ontologies

Keywords
Biological process	Host-virus interaction Viral penetration into host nucleus Virus entry into host cell
Cellular component	Host nucleus Virion
Ligand	RNA-binding Viral nucleoprotein
Molecular function	Ribonucleoprotein
Gene Ontology (GO)
Biological_process	viral entry into host cell Inferred from electronic annotation. Source: UniProtKB-KW viral penetration into host nucleus Inferred from electronic annotation. Source: UniProtKB-KW
Cellular_component	host cell nucleus Inferred from electronic annotation. Source: UniProtKB-SubCell ribonucleoprotein complex Inferred from electronic annotation. Source: UniProtKB-KW virion Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	RNA binding Inferred from electronic annotation. Source: UniProtKB-KW structural molecule activity Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 498	498	Nucleoprotein		PRO_0000079131
Regions
	Motif	1 – 18	18	Unconventional nuclear localization signal By similarity
	Motif	198 – 216	19	Bipartite nuclear localization signal By similarity

Sequences

	Sequence		Length	Mass (Da)
	P26078 [UniParc]. Last modified May 1, 1992. Version 1. Checksum: 4F761D5E4D721B76	FASTA	498	56,169
	10 20 30 40 50 60 MASQGTKRSY EQMETGGERQ NATEIRASVG RMIGGIGRFY IQMCTELKLS DYEGRLIQNS 70 80 90 100 110 120 ITIERMVLSA FDERRNKYLE EHPSAGKDPK KTGGPIYRRI DGKWIRELIL YDKEEIRRIW 130 140 150 160 170 180 RQANNGEDAT AGLTHMMIWH SNLNDATYQR TRALVRTGMD PRMCSLMQGS TLPRRSGAAG 190 200 210 220 230 240 AAVKGVGTMV MELIRMIKRG INDRNFWRGE NGRRTRIAYE RMCNILKGKF QTAAQRAMMD 250 260 270 280 290 300 QVRESRNPGN AEIEDLIFLA RSALILRGSV AHKSCLPACV YGLAVASGHD FEREGYSLVG 310 320 330 340 350 360 IDPFRLLQNS QVFSLIRPNE NPAHKSQLVW MACHSAAFED LRVSSFIRGK KVVPRGQLST 370 380 390 400 410 420 RGVQIASNEN METMDSSTLE LRSRYWAIRT RSGGNTNQQR ASAGQISVQP TFSVQRNLPF 430 440 450 460 470 480 ERATVMAAFT GNTEGRTSDM RTEIIRIMES ARPEDVSFQG RGVFELSDEK ATSPIVPSFD 490 MSNEGSYFFG DNAEEYDN

References

[1]

"Evolution of influenza A virus nucleoprotein genes: implications for the origins of H1N1 human and classical swine viruses." Gorman O.T., Bean W.J., Kawaoka Y., Donatelli I., Guo Y., Webster R.G. J. Virol. 65:3704-3714(1991) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC RNA].

Cross-references

Sequence databases
EMBL GenBank DDBJ	M63758 Genomic RNA. Translation: AAA52257.1.
3D structure databases
ProteinModelPortal	P26078.
SMR	P26078. Positions 22-496.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
InterPro	IPR002141. Flu_NP. [Graphical view]
Pfam	PF00506. Flu_NP. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

NCAP_I42A0

Accession

Primary (citable) accession number: P26078

Entry history

Integrated into UniProtKB/Swiss-Prot:	May 1, 1992
Last sequence update:	May 1, 1992
Last modified:	April 3, 2013
This is version 48 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Viral Protein Annotation Program