Table II. Glycine at the –3 position does not influence readthrough.

Sequencea							Readthrough efficiency (%)	Vector name
GGC	GGG	CAA	TAG	CAA	AGA	GT?	10	(pAC-STE6)b
G	G	Q	*	Q	R	V
GGA	TCT	CAA	TAG	CAA	GCA	AGC	16	(pAC-QXQ)b
G	S	Q	*	Q	A	S
GGA	ACA	CAA	TAG	CAA	TTA	CAG	23	(pAC-TMV)
G	T	Q	*	Q	L	Q
AAA	CCA	CAA	TAG	CAA	GAA	TAT	2.2	(pAC-CAAp)
K	P	Q	*	Q	E	Y
GGA	ACA	---	---	---	---	---	2.3	(pAC-gga-2)
G	T

^aNucleotides changed are indicated in bold. ? indicates unknown nucleotide corresponding to cloning site.

^bSTE6 and QXQ sequences have been described by Bedwell’s group (Fearon et al., 1994; Bonetti et al., 1995).