Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, also known as 2019 novel coronavirus (2019-nCoV)) is the strain of coronavirus that causes coronavirus disease 2019 (COVID-19), a contagious respiratory illness. Coronaviruses possess the largest genomes among any RNA viruses. This page summarizes some key features of the SARS-CoV-2 virus, based on NCBI's analysis of the virus's genome sequence. In particular, it lists some important genes that have been identified in the genome, along with the conserved domains that have been identified on the transcribed proteins. It also provides links to 3D protein structures, as available. The "SARS Cov-2 structure, representative" column lists 3D structures for CoV-2 protein sequences that are included in the multiple sequence alignment of the conserved domain model. If a CoV-2 protein is not yet available for a given gene, then a link is provided for a representative SARS structure, or for a related coronavirus structure, as available.

The data in the table below are organized to reflect the two major types of genes/proteins on the SARS-CoV-2, which is a positive-sense single-stranded RNA virus.

The genome contains several essential genes that encode the viral proteins necessary for replication, transcription and infectious virus assembly. The essential genes comprise the open reading frames 1a and 1b (ORF1ab) that are translated to produce 16 mature nonstructural proteins (nsp1-nsp16, numbered according to their order from the N-terminus to the C-terminus of the ORF 1 polyproteins) that are involved in viral RNA replication and transcription.

In addition to these genes, SARS-CoV-2 contains genes that encode four structural proteins which are involved in infectious virus assembly: (S)pike, (E)nvelope), (M)embrane, and (N)ucleocapsid) proteins. The N protein holds the RNA genome, and the S, E, and M proteins together create the viral envelope. The spike protein is responsible for allowing the virus to attach to and fuse with the membrane of a host cell. Interspersed between these genes in the coronavirus genome are several other genes called "group-specific or accessory genes" and their gene products are called "accessory proteins" that are dispensable for virus growth in vitro, but may play an important role in modulating the host response to virus infection and thereby, contribute to pathogenesis.

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