Question

Why does the M protein of Rhabdovirus enter the nucleus after the virion enters the host cell?

Answer 1

ANSWER :-

1. The M protein of the Rhabdovirus also called as the matrix protein forms a layer or envelope outside the ribonucleoprotein which comprises the single stranded RNA of the virus.
2. This protein plays a pivotal role in the condensation of the RNA into the core of the cell thereby mediating its effect in stabilizing the viral genome and at the time of infection, there is need of converting the negative strand (antisense) to a sense strand to mediate its replication.
3. Apart from this, M protein also plays a vital role in the process of viral budding in which the viral cell in a coordinated manner (with interactions between the M protein and G protein or spike protein of the virus) mediate the release of the pathogenic viral cells called as the virions post infection and replication.
4. At the time of infection, the viral genome should undergo progression into the decondensed form in order to mediate viral replication and hence it migrates to the nucleus of the host cell mainly to mediate interaction between the cellular machinery associated with replication and the ribonucleoprotein. There are varied roles played by the M protein but it should be taken into consideration that the nucleus specific entry of viral genome needs the envelope to be removed along with interaction of nucleoprotein complex with the host replication machinery followed by replication and release of new virions. The interaction and release through budding is effectively carried out by the M protein.