TABLE 6.

A quadruple ski mutant is similar to an ski7 mutant^a

Strain	C+ A− RNA	Initial rate	Ft1/2	Maximum activity
Quadruple mutant 3963 (ski2::HIS3 ski3::URA3 ski7::HIS3 ski8::HIS3)	UTR 24b	18.6	18	5.0
	UTR 64b	25.7	41	9.7
	UTR 104b	26.2	32.5	11.0
Single mutant 3975 (ski7::HIS3)	UTR 24b	17.9	18.5	4.3
	UTR 64b	24.5	32	8.8
	UTR 104b	30.2	32.5	13.2

^aStrain 3963 or 3975 was electroporated with the indicated C⁺ A⁻ mRNAs, and the kinetics of luciferase synthesis were measured as described in Materials and Methods. Initial rate, initial rate of luciferase expression in light units (×100) per minute per microgram of protein. Ft_1/2, functional stability in minutes. Maximum activity is reported in light units per microgram of protein. The control had 0.005 light unit/μg of protein.