Ji S D, Wang Z Y, Fan H J, Zhang R S, Yu Z Y, Wang J J, Liu Z H
School of Forestry, Northeast Forestry University, 26 Hexing Road, 150040, Harbin, China.
The College of Landscape, Northeast Forestry University, 26 Hexing Road, 150040, Harbin, China.
J Plant Res. 2016 Sep;129(5):921-933. doi: 10.1007/s10265-016-0829-9. Epub 2016 May 19.
The tolerance of plants to biotic and abiotic stresses could be improved by transforming with fungal resistance-related genes. In this study, the cDNA sequence (GenBank Acc. No. KP337939) of the resistance-related gene Hsp24 encoding the 24 kD heat shock protein was obtained from the biocontrol fungus Trichoderma asperellum ACCC30536. The promoter region of Hsp24 contained many cis-regulators related to stresses response, such as "GCN4" and "GCR1" etc. Hsp24 transcription in T. asperellum was up-regulated under six different environmental stresses, compared with the control. Furthermore, following heterologous transformation into Populus davidiana × P. alba var. Pyramidalis (Pdpap), Hsp24 was successfully transcribed in transformant Pdpap-Hsp24s. Pathogen-related genes (PRs) in four Pdpap-Hsp24s were up-regulated compared with those in the control Pdpap (Pdpap-Con). After co-culture of Pdpap-Hsp24s with the weak parasite Cytospora chrysosperma, the transcription of genes related to hormone signal pathway (JA and SA) were up-regulated in Pdpap-Hsp24s, and ethidium bromide (EtBr) and Nitro-blue tetrazolium (NBT) staining assays indicated that the cell membrane permeability and the active oxygen content of Pdpap-Hsp24s leaves were lower than that of the control Pdpap-Con. And when the Pdpap-Hsp24s were under the Alternaria alternate stress, the activities of superoxide dismutase (SOD) and peroxidase (POD) got higher in Pdpap-Hsp24s than that in Pdpap-Con, and the disease spots in Pdpap-Con leaves were obviously larger than those in Pdpap-Hsp24s leaves. In summary, Hsp24 of T. asperellum ACCC30536 is an important defense response gene, and its heterologous expression improved the resistance of transformant Pdpap-Hsp24s to C. chrysosperma and A. alternate.
通过导入与真菌抗性相关的基因，可以提高植物对生物和非生物胁迫的耐受性。在本研究中，从生防真菌棘孢木霉ACCC30536中获得了编码24 kD热激蛋白的抗性相关基因Hsp24的cDNA序列（GenBank登录号：KP337939）。Hsp24的启动子区域包含许多与胁迫响应相关的顺式作用元件，如“GCN4”和“GCR1”等。与对照相比，在六种不同环境胁迫下，棘孢木霉中Hsp24的转录上调。此外，将其异源转化到山杨×新疆杨中后，Hsp24在转化体Pdpap-Hsp24s中成功转录。与对照Pdpap（Pdpap-Con）相比，四个Pdpap-Hsp24s中的病程相关基因（PRs）上调。Pdpap-Hsp24s与弱寄生菌金黄壳囊孢共培养后，Pdpap-Hsp24s中与激素信号途径（JA和SA）相关的基因转录上调，溴化乙锭（EtBr）和氮蓝四唑（NBT）染色分析表明，Pdpap-Hsp24s叶片细胞膜通透性和活性氧含量低于对照Pdpap-Con。当Pdpap-Hsp24s受到链格孢胁迫时，Pdpap-Hsp24s中超氧化物歧化酶（SOD）和过氧化物酶（POD）的活性高于Pdpap-Con，且Pdpap-Con叶片上的病斑明显大于Pdpap-Hsp24s叶片上的病斑。综上所述，棘孢木霉ACCC30536的Hsp24是一个重要的防御反应基因，其异源表达提高了转化体Pdpap-Hsp24s对金黄壳囊孢和链格孢的抗性。
