This family includes movement proteins from various viruses. The 3A protein is found in bromoviruses and Cucumoviruses. The genome of these viruses contain 3 RNA segments. The third segment (RNA 3) contains two proteins, the coat protein and the 3A protein. The function of the 3A protein is uncertain but has been shown to be involved in cell-to- cell movement of the virus. The family also includes movement proteins from Dianthoviruses.
Jiyao W et al.(2023). "The conserved domain database in 2023.",