Table 17.2.

Functions and Terminology of Virion Proteins in the Families Paramyxoviridae and Pneumoviridae

Function	Virion Protein
	Genera Aquaparamyxovirus, Avulavirus, Ferlavirus, Respirovirus, and Rubulavirus	Genus Morbillivirus	Genus Henipavirus, Orthopneumovirus, and Metapneumovirus
Attachment protein: hemagglutinin, induction of productive immunity	HN	H	Ga
Neuraminidase: virion release, destruction of mucin inhibitors	HN	None	None
Fusion protein: cell fusion, virus penetration, cell–cell spread, contribution to induction of protective immunity	F	F	F
Nucleoprotein: protection of genome RNA	N	N	N
Transcriptase: RNA genome transcription	L and P/C/V	L and P/C/V	L and P
Matrix protein: virion stability	M	M	M
Other	(SH)	–	SH, M2

^aNo hemagglutinating activity.