To understand whether methanol- or ethanol-promoted plant growth is related to the synthesis of gibberellin (GA),we investigated the effects of exogenous GA and paclobutrazol(PAC),an inhibitor of GA synthesis,on 2 mmol/L methanol- and ethanol-stimulated growth of tobacco on MS agar medium and analyzed the molecular mechanism of RSG,the GA synthesis-regulated transcription factor,in response to methanol- and ethanol-stimulation in tobacco.The results showed that:(1)The addition of exogenous GA enhanced the stimulation of methanol and ethanol on tobacco growth while addition of PAC inhibited their stimulation to tobacco growth.(2)The binding of 14-3-3 proteins with RSG inhibits RSG transport into nucleus and reduced its transcriptional regulatory activity.Methanol and ethanol induced transcription and expression of 14-3-3 genes as well as RSG protein expression.(3)Methanol and ethanol reduced the interaction of 14-3-3 proteins and RSG while enhanced the binding of RSG to GA20ox1 promoter.These results indicated that methanol- and ethanol-stimulated tobacco growth might be achieved through increasing nuclear localization of RSG by inducing RSG expression and simultaneously reducing the interaction of RSG with 14-3-3 proteins.Consequently,the binding of RSG and GA20ox1 promoter was enhanced and GA protein synthesis increased,thereby promoting the growth of tobacco.These changes might consist of an important molecular mechanism underlying methanol- and ethanol-promoted tobacco growth.