Recombinant SARS-CoV-2, Nucleocapsid (N) Protein

Severe acute respiratory syndrome coronavirus 2 (SARSCoV2), the causative agent of coronavirus disease 2019 (COVID19), is an enveloped, singlestranded, positivesense RNA virus that belongs to the Coronaviridae family¹. The SARSCoV2 genome, which shares 79.6% identity with SARSCoV, encodes four essential structural proteins: the spike (S), envelope (E), membrane (M), and nucleocapsid protein (N)². The N protein is 46 kDa and consists of two highly conserved structural domains, the Nterminal domain (NTD) and Cterminal domain (CTD), connected by a linker region. The NTD and CTD are involved in RNA binding and selfoligomerization, respectively^3,4. The primary function of the N protein is to bind to and package the viral RNA genome into a helical ribonucleoprotein complex⁵. The N protein is also involved in other critical steps of the viral life cycle, including transcription, replication, and modulating infected cell signaling pathways^6,7. The N protein is abundantly expressed during infection and is highly conserved, sharing 90% amino acid homology with the SARSCoV N protein (8). It is also immunogenic, and antibodies^8,9 and memory T cells ^10,11 targeting the N protein are present in the sera of convalescent COVID19 patients, identifying the N protein as a suitable candidate for vaccine development and diagnostic assays. Diagnostic assays based on the N protein effectively detect antibodies in the sera of patients infected with SARSCoV2¹². The N protein also contributes to immune evasion by antagonizing antiviral RNAi¹³, suggesting its potential value as a targeted therapeutic.

MSDNGPQNQRNAPRITFGGPSDSTGSNQNGERSGARSKQRRPQGLPNNTASWFTALTQHGKEDLKFPRGQGVPINTNSSPDDQIGYYRRATRRIRGGDGKMKDLSPRWYFYYLGTGPEAGLPYGANKDGIIWVATEGALNTPKDHIGTRNPANNAAIVLQLPQGTTLPKGFYAEGSRGGSQASSRSSSRSRNSSRNSTPGSSRGTSPARMAGNGGDAALALLLLDRLNQLESKMSGKGQQQQGQTVTKKSAAEASKKPRQKRTATKAYNVTQAFGRRGPEQTQGNFGDQELIRQGTDYKHWPQIAQFAPSASAFFGMSRIGMEVTPSGTWLTYTGAIKLDDKDPNFKDQVILLNKHIDAYKTFPPTEPKKDKKKKADETQALPQRQKKQQTVTLLPAADLDDFSKQLQQSMSSADSTQA

Liquid

The predicted molecular weight of Recombinant SARSCoV2, Nucleocapsid (N) Protein is Mr 47 kDa.

47 kDa

This recombinant protein is aseptically packaged and formulated in 0.01 M phosphate buffered saline (PBS) pH 7.2 7.4, 150 mM NaCl with no carrier protein, potassium, calcium or preservatives added. Due to inherent biochemical properties of proteins, certain products may be prone to precipitation over time. Precipitation may be removed by aseptic centrifugation and/or filtration.

We recommended to store this recombinant protein as received at 28°C for up to one month. For longerterm storage, aseptically aliquot in working volumes without diluting and store at 80°C. Avoid Repeated Freeze Thaw Cycles.

Blue Ice via Next Day Air

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