This product is encoded by astrovirus ORF2, one of the three astrovirus ORFs (1a, 1b, 2). The 87kD precursor protein undergoes an intracellular cleavage to form a 79kD protein. Subsequently, extracellular trypsin cleavage yields the three proteins forming the infectious virion.
Jiyao W et al.(2023). "The conserved domain database in 2023.",