Plays a major role in assembly and budding of virion. Completely covers the ribonucleoprotein coil and keep it in condensed bullet-shaped form. Inhibits viral transcription and stimulates replication (By similarity). Homomultimer. Interacts with nucleoprotein and with the cytoplasmic domain of glycoprotein (By similarity). Most abundant protein in the virion. Belongs to the nucleorhabdovirus type-2 matrix protein family.