泛素融合降解蛋白基因UFD1对植物抗病和抗逆性的调控功能分析

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

采用反转录-聚合酶链反应(reverse transcription-polymerase chain reaction,RT-PCR)克隆获得1个番茄泛素融合降解蛋白(ubiquitin fusion degradation protein,UFD)基因片段UFD1,并应用病毒诱导的基因沉默(virus-induced gene silencing,VIGS)技术分析该基因对植物抗病性和抗逆性的调控功能.结果表明:在本氏烟(Nicotiana benthamiana)植株中UFD1基因的沉默导致Cf-4/Avr4和Cf-9/Avr9介导的过敏性反应(hypersensitive response,HR)以及水稻白叶枯病菌(Xanthomonas oryzae pv.oryzae,Xoo)诱导的HR显著减弱,烟草野火病坏死症状明显减轻,在高盐胁迫下叶片叶绿素含量显著降低,但对菌核病病害症状以及抗干旱能力的影响不明显.表明UFD1基因是植物抗病和抗逆性的重要调控因子,它可能对Cf-4/Cf-9介导的基因对基因抗性、对Xoo的非寄主抗性和耐盐性起正向调控作用,而对烟草野火病抗性起负调控作用.

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.