Molecular biology
VIRION
Enveloped, bullet shaped. 180 nm long and 75 nm wide.
GENOME
Negative-stranded RNA linear genome, about 14.6-14.8 kb in size. Encodes for 5 to 9 proteins.
GENE EXPRESSION
The viral RNA dependent RNA polymerase binds the encapsidated genome at the leader region, then sequentially transcribes each genes by recognizing start and stop signals flanking viral genes. mRNAs are capped and polyadenylated by the L protein during synthesis.
REPLICATION
CYTOPLASMIC- Virus attaches to host receptors though G glycoprotein and is endocytosed into vesicles in the host cell.
- Fusion of virus membrane with the vesicle membrane; ribonucleocapsid is released into the cytoplasm.
- sequential transcription, viral mRNAs are capped and polyadenylated in the cytoplasm.
- Replication presumably starts when enough nucleoprotein is present to encapsidate neo-synthetized antigenomes and genomes.
- The ribonucleocapsid interacts with the matrix protein under the plasma membrane M protein and buds from the plasma membrane, releasing the virion.