Stimulation of synthesis and translational activity of polyadenylated messenger RNA in wounded potato tubers by 2, 4-dichlorophenoxyacetic acid

Mechanical wounding of potato tubers induced a rapid synthesis of RNA in the wounded tissues. Both total and polyadenylated RNA increased with time after wounding. Treatment of wounded tissues with the synthetic hormone 2,4-dichlorophenoxyacetic acid (2,4-D, 10^?4 M) further stimulated their syntheses. The poly (A) ⁺RNA from hormone treated tissues was more active in in vitro protein synthesis. The in vitro translation of poly (A) ⁺RNA from both hormone treated and untreated tissues was inhibited by 7-methylguanosin-5′ phosphate, while 7-methylguanosine had no effect, suggesting that both poly (A) ⁺RNAs contained a blocked 5′-cap structure and that the cap structure was important for in vitro protein synthesis.