TABLE 3.

Cotransfection of transformation-defective SU and TM mutants in 208F cells^a

JSRV Env protein	No. of transformed foci at weekb:						No. of colonies picked at weekb 4c	No. of re-formed focid
	2	3	4	5	6	7
Expt I
Mock	0	0	0	0	0	0	ND	ND
PCDNA 3.1	0	0	0	0	0	0	ND	ND
ΔGP	23 ± 5.5	101 ± 20	128 ± 17	TMTC			3	3/3
ΔGP SUΔ103-352	0	0	0	0	0	0	ND	ND
ΔGP Y590F	0	0	0	0	0	0	ND	ND
ΔGP Y590F + ΔGP SUΔ103-352	9 ± 1	21 ± 2	28 ± 8	46 ± 6.5	61 ± 6	69 ± 4.5	6	6/6
ΔGP Y590FHA	0	0	0	0	0	0	ND	ND
ΔGP SUΔ103-352HA	0	0	0	0	0	0	ND	ND
ΔGP Y590FHA + ΔGP SUΔ103-352HA	0	1 ± 1	5 ± 2	13 ± 2	22 ± 3	27 ± 1	3	3/3
Expt 2
Mock	0	0	0	0	0	0	ND	ND
PCDNA 3.1	0	0	0	0	0	0	ND	ND
ΔGP	36 ± 4	70 ± 13	140 ± 26	TMTC			3	3/3
ΔGP SUΔ103-352	0	0	0	0	0	0	ND	ND
ΔGP SuxTMen	0	0	0	0	0	0	ND	ND
ΔGP SuxTMen + ΔGP SUΔ103-352	0	15 ± 2	16 ± 2	17 ± 1	23 ± 4	26 ± 4	3	3/3
Expt 3e
Mock	0	0	0	0			ND	ND
PCDNA 3.1	0	0	0	0			ND	ND
ΔGP	29	116	TMTC				ND	ND
ΔGP Y590F + ΔGP SUΔ103-352	3	6	7	13			ND	ND
ΔGP Y590F + ΔGP SUΔ253-302HA	0	2	4	9			ND	ND

^aDiagrams of the two constructs used in the cotransfection/transformation assay are in Fig. 4.

^bAll transfections were performed three times, and the average number of foci at each time is indicated along with the average deviation from the mean. Numbers where no errors are given represent the total foci observed in the three experiments. TMTC, too many to count.

^cNumber of foci isolated from initial transfectants at 4 weeks posttransfection. ND, not done.

^dIsolated colonies were reseeded in a six-well plate and assayed for their ability to reform foci 2 weeks posttransfer. Results are expressed as number of colonies re-forming transformed foci/number of colonies picked.

^eExperiment 3 values represent transformed foci from a single assay.