Functional analysis of an ubiquitin fusion degradation protein gene UFD1 in regulation of plant disease and stress resistance

LAI Yi-yu1,LI Fei1,XU You-ping2,CAI Xin-zhong1,3( 1.Institute of Biotechnology,Zhejiang University,Hangzhou 310058,China;2.Centre of Analysis and Measurement,Zhejiang University,Hangzhou 310058,China;3.Key Laboratory of Molecular Biology of Crop Pathogens and Insects,Ministry of Agriculture,Zhejiang University,Hangzhou 310058,China)

ubiquitin fusion degradation protein;virus-induced gene silencing;disease resistance;stress resistance;Nicotiana benthamiana

A fragment of ubiquitin fusion degradation protein(UFD) gene UFD1 was cloned from tomato by reverse transcription-polymerase chain reaction(RT-PCR),and its role in regulation of plant disease and stress resistance was analyzed employing virus-induced gene silencing(VIGS) technique.The results showed that the silencing of UFD1 in Nicotiana benthamiana resulted in significantly weakening of hypersensitive response(HR) mediated by Cf-4/Avr4-and Cf-9/Avr9 and induced by Xanthomonas oryzae pv.oryzae(Xoo),alleviating of necrotic symptoms of tobacco wild fire disease,decreasing of chlorophyll content in leaves under stress of high concentration of salt,but did not lead to change of symptoms of white mould disease caused by Sclerotinia sclerotiorum and resistance to drought stress.It is indicated that UFD1 is a pivotal regulator of plant disease and stress resistance,playing roles in positive regulation of Cf-4-and Cf-9-dependent gene-for-gene resistance,nonhost resistance to Xoo and salt tolerance,and in contrast,negative regulation of resistance to tobacco wild fire disease.