3.6. Orf6
The orf6 of the SARS-CoV-2 and the BatCoV RaTG13 contain 61 amino acids
while it contains 63 amino acids in the SARS-CoV (Table 1). The orf6
proteins of the SARS-CoV-2 and SARS-CoV are characterized by identity
percentage of 68.9% and similarity percentage of 88.5%. The identity
and similarity percentages of the orf6 of the SARS-CoV-2 and BatCoV
RaTG13 were 100% each (Table.2).
The functions of the orf6 include: 1) it participates the formation of
replication\transcription to facilitate the viral
replication, 2) it increases the number of the virions during the
infection, 3) it contributes to the evasion of the virus to the host
immune system and 4) it is involved in the formation of the Double
Membrane Vesicle (DMV) in the host cells to ensure the virus assembling
[40-42].