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Q90021 (NRAM_INBYB) Reviewed, UniProtKB/Swiss-Prot

Last modified February 19, 2014. Version 85. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Neuraminidase

EC=3.2.1.18
Gene names
Name:NA
OrganismInfluenza B virus (strain B/Yamagata/16/1988)
Taxonomic identifier416674 [NCBI]
Taxonomic lineageVirusesssRNA negative-strand virusesOrthomyxoviridaeInfluenzavirus B
Virus hostHomo sapiens (Human) [TaxID: 9606]

Protein attributes

Sequence length466 AA.
Sequence statusComplete.
Protein existenceInferred from homology

General annotation (Comments)

Function

Catalyzes the removal of terminal sialic acid residues from viral and cellular glycoconjugates. Cleaves off the terminal sialic acids on the glycosylated HA during virus budding to facilitate virus release. Additionally helps virus spread through the circulation by further removing sialic acids from the cell surface. These cleavages prevent self-aggregation and ensure the efficient spread of the progeny virus from cell to cell. Otherwise, infection would be limited to one round of replication. Described as a receptor-destroying enzyme because it cleaves a terminal sialic acid from the cellular receptors. May facilitate viral invasion of the upper airways by cleaving the sialic acid moities on the mucin of the airway epithelial cells By similarity.

Catalytic activity

Hydrolysis of alpha-(2->3)-, alpha-(2->6)-, alpha-(2->8)- glycosidic linkages of terminal sialic acid residues in oligosaccharides, glycoproteins, glycolipids, colominic acid and synthetic substrates.

Enzyme regulation

Inhibited by the neuraminidase inhibitors zanamivir (Relenza) and oseltamivir (Tamiflu). These drugs interfere with the release of progeny virus from infected cells and are effective against all influenza strains. Resistance to neuraminidase inhibitors is quite rare.

Subunit structure

Homotetramer By similarity.

Subcellular location

Virion membrane By similarity. Host apical cell membrane; Single-pass type II membrane protein By similarity. Note: Preferentially accumulates at the apical plasma membrane in infected polarized epithelial cells, which is the virus assembly site. In the virion, forms a mushroom-shaped spike on the surface of the membrane By similarity.

Post-translational modification

N-glycosylated By similarity.

Miscellaneous

The influenza B genome consist of 8 RNA segments. Genetic variation of hemagglutinin and/or neuraminidase genes results in the emergence of new influenza strains. The mechanism of variation can be the result of point mutations or the result of genetic reassortment between segments of two different strains.

Sequence similarities

Belongs to the glycosyl hydrolase 34 family.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 466466Neuraminidase
PRO_0000078741

Regions

Topological domain1 – 66Intravirion Potential
Transmembrane7 – 3529Helical; Signal-anchor for type II membrane protein; Potential
Topological domain36 – 466431Virion surface Potential
Region39 – 6931Hypervariable stalk region
Region70 – 466397Head of neuraminidase

Sites

Active site1491 Potential
Active site2751 Potential
Active site4091 Potential
Binding site1161Substrate Potential
Binding site2921Substrate Potential
Binding site3741Substrate Potential

Amino acid modifications

Glycosylation561N-linked (GlcNAc...); by host Potential
Glycosylation641N-linked (GlcNAc...); by host Potential
Glycosylation1441N-linked (GlcNAc...); by host Potential
Glycosylation2841N-linked (GlcNAc...); by host Potential
Disulfide bond87 ↔ 420 By similarity
Disulfide bond122 ↔ 127 By similarity
Disulfide bond182 ↔ 229 By similarity
Disulfide bond231 ↔ 236 By similarity
Disulfide bond277 ↔ 291 By similarity
Disulfide bond279 ↔ 289 By similarity
Disulfide bond318 ↔ 337 By similarity
Disulfide bond424 ↔ 447 By similarity

Sequences

Sequence LengthMass (Da)Tools
Q90021 [UniParc].

Last modified November 1, 1996. Version 1.
Checksum: 7B698B44205288A6

FASTA46651,365
        10         20         30         40         50         60 
MLPSTIQTLT LFLTSGGVLL SLYVSASLSY LLYSDILLKF SPTEITAPKV PLDCANASNV 

        70         80         90        100        110        120 
QAVNRSATKG MTLLLSEPEW TYPRLSCQGS TFQKALLISP HRFGESRGNS APLIIREPFI 

       130        140        150        160        170        180 
ACGPKECKHF ALTHYAAQPG GYYNGTREDR NKLRHLISVK LGKIPTVENS IFHMAAWSGS 

       190        200        210        220        230        240 
ACHDGREWTY IGVDGPDSNA LIKIKYGEAY TDTYHSYANN ILRTQESACN CIGGDCYLMI 

       250        260        270        280        290        300 
TDGSASGISK CRFLKIREGR IIKEIFPTGR VEHTEECTCG FASNKTIECA CRDNSYTAKR 

       310        320        330        340        350        360 
PFVKLNVETD TAEIRLMCTE TYLDTPRPDD GSITGPCESN GDKGRGGIKG GFVHQRMASK 

       370        380        390        400        410        420 
IGRWYSRTMS KTERMGMELY VKYDGDPWTD SDALAPSGVM VSMKEPGWYS FGFEIKDKKC 

       430        440        450        460 
DVPCIGIEMV HDGGKKTWHS AATAIYCLMG SGQLLWDTVT GVDMAL 

« Hide

References

[1]"Comparison of structure and sequence of influenza B/Yamagata and B/Beijing neuraminidases shows a conserved 'head' but much greater variability in the 'stalk' and NB protein."
Burmeister W.P., Baudin F., Cusack S., Ruigrok R.W.H.
Virology 192:683-686(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [GENOMIC RNA].
[2]"Neuraminidase inhibitors for influenza."
Moscona A.
N. Engl. J. Med. 353:1363-1373(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
X67013 Genomic RNA. Translation: CAA47401.1.
PIRS23855.

3D structure databases

ProteinModelPortalQ90021.
SMRQ90021. Positions 77-466.
ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Family and domain databases

Gene3D2.120.10.10. 1 hit.
InterProIPR001860. Glyco_hydro_34.
IPR011040. Sialidases.
[Graphical view]
PfamPF00064. Neur. 1 hit.
[Graphical view]
SUPFAMSSF50939. SSF50939. 1 hit.
ProtoNetSearch...

Entry information

Entry nameNRAM_INBYB
AccessionPrimary (citable) accession number: Q90021
Entry history
Integrated into UniProtKB/Swiss-Prot: December 15, 1998
Last sequence update: November 1, 1996
Last modified: February 19, 2014
This is version 85 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programViral Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

Glycosyl hydrolases

Classification of glycosyl hydrolase families and list of entries