Dm. Rhoads et L. Mcintosh, CYTOCHROME AND ALTERNATIVE PATHWAY RESPIRATION IN TOBACCO - EFFECTS SALICYLIC-ACID, Plant physiology, 103(3), 1993, pp. 877-883
In suspension cultures of NT1 tobacco (Nicotiana tabacum L. cv Bright
Yellow) cells the cytochrome pathway capacity increased between d 3 an
d d 4 following subculturing and reached the highest level observed on
d 7. The capacity decreased significantly by d 10 and was at the same
level on d 14. Both alternative pathway capacity and the amount of th
e 35-kD alternative oxidase protein increased significantly between d
5 and d 6, reached the highest point observed on d 7, remained constan
t until d 10, and decreased by d 14. The highest capacities of the alt
ernative and cytochrome pathways and the highest amount of the 35-kD p
rotein were attained on the day that cell cultures reached a stationar
y phase of growth. Addition of salicylic acid to cell cultures on d 4
caused a significant increase in alternative pathway capacity and a dr
amatic accumulation of the 35-kD protein by 12 h. The alternative path
way capacity and the protein level reached the highest level observed
by 16 h after salicylic acid addition, and the cytochrome pathway capa
city was at about the same level at each time point. The accumulation
of the 35-kD alternative oxidase protein was significantly decreased b
y addition of actinomycin D 1 h before salicylic acid and was blocked
by addition of cycloheximide. These results indicate that de novo tran
scription and translation were necessary for salicylic acid to cause t
he maximum accumulation of the 35-kD protein.