|
ORF3b
ORF3b is a gene found in coronaviruses of the subgenus ''Sarbecovirus'', encoding a short non-structural protein. It is present in both SARS-CoV (which causes the disease SARS) and SARS-CoV-2 (which causes COVID-19), though the protein product has very different lengths in the two viruses. The encoded protein is significantly shorter in SARS-CoV-2, at only 22 amino acid residues compared to 153-155 in SARS-CoV. Both the longer SARS-CoV and shorter SARS-CoV-2 proteins have been reported as interferon antagonists. It is unclear whether the SARS-CoV-2 gene expresses a functional protein. Nomenclature There has been significant confusion in the scientific literature around the nomenclature used for the accessory proteins of SARS-CoV-2, especially several overlapping genes with ORF3a. Due to differences in the genomes of SARS-CoV and SARS-CoV-2, two distinct open reading frames (ORFs) in the SARS-CoV-2 genome have been referred to as "ORF3b". In SARS-CoV, ORF3b is a gene of 155 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ORF3d
ORF3d is a gene found in SARS-CoV-2 (the virus that causes COVID-19) and at least one closely related coronavirus found in pangolins, though it is not found in other closely related viruses within the ''Sarbecovirus'' subgenus. It is 57 codons long and encodes a novel 57 amino acid residue protein of unknown function. At least two isoforms have been described, of which the shorter 33-residue form, ORF3d-2, may be more highly expressed, or even the only form expressed. It is reported to be antigenic and antibodies to the ORF3d protein occur in patients recovered from COVID-19. There is no homolog in the genome of the otherwise closely related SARS-CoV (which causes the disease SARS). Nomenclature There has been significant confusion in the scientific literature around the nomenclature used for the accessory proteins of SARS-CoV-2, especially several overlapping genes with ORF3a. Many scientific papers have referred to ORF3d and its protein product as ORF3b, due to confusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |