Human Coronavirus Nucleocapsid Protein

What is Nucleocapsid Protein?

The nucleocapsid protein (N-protein) is the most abundant protein in coronavirus. The N-protein is a highly immunogenic phosphoprotein, and it is normally very conserved. The N protein of coronavirus is often used as a marker in diagnostic assays. During virion assembly, N protein binds to viral RNA and leads to formation of the helical nucleocapsid. The abundance and high hydrophilicity of N protein are supposed to contribute to potent immunity after coroanvirus infection.

Nucleocapsid Protein Function

The N protein constitutes the only protein present in the nucleocapsid. It is composed of two separate domains, an N-terminal domain (NTD) and a C-terminal domain (CTD), both capable of binding RNA in vitro, but each domain uses different mechanisms to bind RNA.

N protein is also heavily phosphorylated, and phosphorylation has been suggested to trigger a structural change enhancing the affinity for viral versus non-viral RNA.

N protein binds the viral genome in a beads-on-a-string type conformation. Two specific RNA substrates have been identified for N protein; the TRSs and the genomic packaging signal. The genomic packaging signal has been found to bind specifically to the second, or C-terminal RNA binding domain.

N protein also binds nsp3, a key component of the replicase complex, and the M protein. These protein interactions likely help tether the viral genome to the replicase-transcriptase complex (RTC), and subsequently package the encapsidated genome into viral particles.
(Ref: Anthony R. Fehr and Stanley Perlman.Coronaviruses: An Overview of Their Replication and Pathogenesis.Methods Mol Biol. 2015)

 

Research Reagents of Nucleocapsid Protein

Sino Biological has developed recombinat proteins, antibodies, genes and other reagents for human coronavirus.

Recombinant Proteins

SARS-CoV-2(2019-nCoV)
SARS-CoV
MERS-CoV
HCoV-229E
HCoV-NL63
HCoV-OC43
HCoV-HKU1
High Purity; Expressed in Insect Cells, closer to Natural Structure;
Cat#:40588-V08B
Purity: >95%
CoV: SARS-CoV-2 (2019-nCoV)

Antibodies

SARS-CoV-2(2019-nCoV)
SARS-CoV
MERS-CoV
High Sensitivity
Cat#:40143-R019
Detection Limit: 0.5ng
CoV: SARS-CoV-2 (2019-nCoV)

Sample: 2019-nCoV NP Protein
(Cat# 40588-V08B)
Lane A: 30ng
Lane B: 10ng
Lane C: 5ng
Lane D: 2ng
Lane E: 1ng
Lane F: 0.5ng

N Protein Detection Kit

Cat#:KIT40588
Assay range: 93.75-6000 pg/mL
Specificity:
Verified by high purity SARS-CoV-2 (2019-nCoV) Nucleocapsid / N Protein (Cat# 40588-V08B) recombinant protein.
Cat#   Antigen More
40068-V08B   MERS-CoV Nucleocapsid Protein

Expressed Host Insect Cells
Tag His
40143-V08B   SARS-CoV Nucleocapsid Protein

Expressed Host Insect Cells
Tag His
40588-V07E   SARS-CoV-2 Nucleocapsid Protein

Expressed Host E. coli
Tag His
40588-V08B   SARS-CoV-2 Nucleocapsid Protein

Expressed Host Insect Cells
Tag His
40588-V08B-B   SARS-CoV-2 Nucleocapsid Protein(Biotinylated)

Expressed Host Insect Cells
Tag His
40588-V27B-B   SARS-CoV-2 Nucleocapsid Protein(Biotinylated)

Expressed Host Insect Cells
Tag AVI-His
40640-V07E   HCoV-229E Nucleocapsid Protein

Expressed Host E. coli
Tag His
40641-V07E   HCoV-NL63 Nucleocapsid Protein

Expressed Host E. coli
Tag His
40642-V07E   HCoV-HKU1 Nucleocapsid Protein

Expressed Host E. coli
Tag His
40643-V07E   HCoV-OC43 Nucleocapsid Protein

Expressed Host E. coli
Tag His
Cat#   Antigen More
40588-R0004   SARS-CoV-2 Nucleocapsid Antibody

Expressed Host Rabbit MAb
Tag Rabbit IgG
40588-T62   SARS-CoV-2 Nucleocapsid Antibody

Expressed Host Rabbit PAb
Tag Rabbit IgG
40143-R019   SARS-CoV-2 Nucleocapsid Antibody

Expressed Host Rabbit MAb
Tag Rabbit IgG
40143-MM05   SARS-CoV Nucleocapsid Antibody

Expressed Host Mouse MAb
Tag Mouse IgG1
40143-MM08   SARS-CoV Nucleocapsid Antibody

Expressed Host Mouse MAb
Tag Mouse IgG1
40143-R001   SARS-CoV Nucleocapsid Antibody

Expressed Host Rabbit MAb
Tag Rabbit IgG
40143-R004   SARS-CoV Nucleocapsid Antibody

Expressed Host Rabbit MAb
Tag Rabbit IgG
40143-R040   SARS-CoV Nucleocapsid Antibody

Expressed Host Rabbit MAb
Tag Rabbit IgG
40143-R040-H   SARS-CoV Nucleocapsid Antibody

Expressed Host Rabbit MAb
Tag Rabbit IgG
40143-RP01   SARS-CoV Nucleocapsid Antibody

Expressed Host Rabbit PAb
Tag Rabbit IgG
40143-T62   SARS-CoV Nucleocapsid Antibody

Expressed Host Rabbit PAb
Tag Rabbit IgG
100213-RP02   MERS-CoV Nucleocapsid Antibody

Expressed Host Rabbit PAb
Tag Rabbit IgG
40068-MM10   MERS-CoV Nucleocapsid Antibody

Expressed Host Mouse MAb
Tag Mouse IgG1
40068-RP01   MERS-CoV Nucleocapsid Antibody

Expressed Host Rabbit PAb
Tag Rabbit IgG
40068-RP02   MERS-CoV Nucleocapsid Antibody

Expressed Host Rabbit PAb
Tag Rabbit IgG
Cat#: KIT40588
Assay range: 93.75-6000 pg/mL
Specificity: The kit has been verified by high purity SARS-CoV-2 (2019-nCoV) Nucleocapsid / N Protein (Cat# 40588-V08B) recombinant protein. It can recognize recombinant SARS-CoV Nucleocapsid / N Protein (His Tag) (Cat# 40143-V08B), but no react with recombinant MERS-CoV Nucleoprotein / NP protein (His Tag) (Cat# 40068-V08B).
Recombinant Antibody Production