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.
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)
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; |
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Cat#:40588-V08B Purity: >95% CoV: SARS-CoV-2 (2019-nCoV) |
Antibodies |
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SARS-CoV-2(2019-nCoV) SARS-CoV MERS-CoV |
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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 |
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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# | Description | Expressed Host | Tag |
40068-V08B | MERS-CoV Nucleocapsid Protein | Insect Cells | His |
40143-V08B | SARS-CoV Nucleocapsid Protein | Insect Cells | His |
40588-V07E | SARS-CoV-2 Nucleocapsid Protein | E. coli | His |
40588-V08B | SARS-CoV-2 Nucleocapsid Protein | Insect Cells | His |
40588-V08B-B | SARS-CoV-2 Nucleocapsid Protein(Biotinylated) | Insect Cells | His |
40588-V27B-B | SARS-CoV-2 Nucleocapsid Protein(Biotinylated) | Insect Cells | AVI-His |
40640-V07E | HCoV-229E Nucleocapsid Protein | E. coli | His |
40641-V07E | HCoV-NL63 Nucleocapsid Protein | E. coli | His |
40642-V07E | HCoV-HKU1 Nucleocapsid Protein | E. coli | His |
40643-V07E | HCoV-OC43 Nucleocapsid Protein | E. coli | His |
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Cat# | Description | Type | Ig Type |
40588-R0004 | SARS-CoV-2 Nucleocapsid Antibody | Rabbit MAb | Rabbit IgG |
40588-T62 | SARS-CoV-2 Nucleocapsid Antibody | Rabbit PAb | Rabbit IgG |
40143-R019 | SARS-CoV-2 Nucleocapsid Antibody | Rabbit MAb | Rabbit IgG |
40143-MM05 | SARS-CoV Nucleocapsid Antibody | Mouse MAb | Mouse IgG1 |
40143-MM08 | SARS-CoV Nucleocapsid Antibody | Mouse MAb | Mouse IgG1 |
40143-R001 | SARS-CoV Nucleocapsid Antibody | Rabbit MAb | Rabbit IgG |
40143-R004 | SARS-CoV Nucleocapsid Antibody | Rabbit MAb | Rabbit IgG |
40143-R040 | SARS-CoV Nucleocapsid Antibody | Rabbit MAb | Rabbit IgG |
40143-R040-H | SARS-CoV Nucleocapsid Antibody | Rabbit MAb | Rabbit IgG |
40143-RP01 | SARS-CoV Nucleocapsid Antibody | Rabbit PAb | Rabbit IgG |
40143-T62 | SARS-CoV Nucleocapsid Antibody | Rabbit PAb | Rabbit IgG |
100213-RP02 | MERS-CoV Nucleocapsid Antibody | Rabbit PAb | Rabbit IgG |
40068-MM10 | MERS-CoV Nucleocapsid Antibody | Mouse MAb | Mouse IgG1 |
40068-RP01 | MERS-CoV Nucleocapsid Antibody | Rabbit PAb | Rabbit IgG |
40068-RP02 | MERS-CoV Nucleocapsid Antibody | Rabbit PAb | Rabbit IgG |
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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). |