TABLE 1.

Gene start (GS) signal sequence-based constraints on RSV transcription initiation probabilities (P _transc ) from Kuo et al. Most RSV/A genomes contain three different GS signal sequences. Kuo et al. performed minigenome studies to quantify the effects on gene expression of all single nt mutations within the GS signal (Kuo et al., 1997). The G gene GS signal contains a single mutation (relative to the most common GS signal sequence) at position 10 that reduced gene expression by ∼35%. Kuo et al. reported that the L gene GS signal gave rise to a magnitude of gene expression equal to that of the most common GS signal. It is therefore reasonable to model RSV transcription with a single probability of transcription initiation at all GS signals except for G, where the probability should be multiplied by 0.65.

RSV gene
NS1,NS2,N,P,M,SH,F,M2		G	L
GS signal sequence	CCCCGUUAU	CCCGUUUAC	CCCUGUUUUA
Effect on Ptransc	--	0.65X	1X (no change)