Table 2. Enhancement conferred by the TMV 5′-leader as a function of the severity of a heat shock.

Temperature	Luciferase expression (light units/min/mg/protein)		Fold stimulation by Ω
	luc-A50	Ω-luc-A50
24°C
60 min	119 000	538 000	4.5
42°C
5 min	118 000	853 000	7.2
10 min	146 000	1 600 000	11
20 min	181 000	1 860 000	10
30 min	241 000	3 890 000	16
40 min	273 000	3 110 000	11
50 min	284 000	4 360 000	15
60 min	251 000	5 130 000	20
43°C
5 min	145 000	981 000	6.8
10 min	190 000	1 590 000	8.4
20 min	247 000	2 110 000	8.6
30 min	225 000	3 100 000	14
40 min	236 000	4 100 000	17
50 min	194 000	4 310 000	22
60 min	146 000	4 050 000	28
44°C
5 min	177 000	868 000	4.9
10 min	213 000	2 160 000	10
20 min	269 000	4 640 000	17
30 min	188 000	4 010 000	21
40 min	71 300	2 330 000	33
50 min	30 100	821 000	27
60 min	19 000	800 000	42

Capped luc-A₅₀ or Ω-luc-A₅₀ mRNAs were synthesized and delivered to carrot protoplasts. Expression from each mRNA construct was determined by measuring cell extract in a luminometer.