TABLE 2.

Phenotypes of rescued viruses containing point mutations in PB2^a

Virus	Plaque size	Virus yield	Protein synthesis	cRNA	vRNA	Primary transcription
Wild type	++++	Normal	Normal	Normal	Normal	Normal
F130Y	+++++	Increased	Normal	Increased	Increased	Normal
R142A	+	Delayed	Delayed	Delayed	Delayed	Normal
R142K	++	Delayed	Delayed	Delayed	Delayed	Normal

^aSee Table 1, footnote a.