College of Horticulture, Gansu Agricultural University, Lanzhou, 730070, People's Republic of China.
Institute of Agriculture and Environment, Massey University, Palmerston North, 4442, New Zealand.
Planta. 2021 Sep 18;254(4):78. doi: 10.1007/s00425-021-03724-y.
51 MdbZIP genes were identified from the apple genome by bioinformatics methods. MhABF-OE improved tolerance to saline-alkali stress in Arabidopsis, indicating it is involved in positive regulation of saline-alkali stress response. Saline-alkali stress is a major abiotic stress limiting plant growth all over the world. Members of the bZIP family play an important role in regulating gene expression in response to many kinds of biotic and abiotic stress, including salt stress. According to the transcriptome data, 51 MdbZIP genes responding to saline-alkali stress were identified in apple genome, and their gene structures, conserved protein motifs, phylogenetic analysis, chromosome localization, and promoter cis-acting elements were analyzed. Based on transcriptome data analysis, a MdbZIP family gene (MD15G1081800), which was highly expressed under stress, was selected to isolate and named as MhABF. Expression profile analysis by quantitative real-time PCR confirmed that the expression of MhABF in the leaves of Malus halliana was 10.6-fold higher than that of the control (0 days) after 2 days of stress. Then an MhABF gene was isolated from apple rootstock M. halliana. CaMV35S promoter drived MhABF gene expression vector was constructed to infect Arabidopsis with Agrobacterium-mediated infection. And overexpression MhABF gene plants were obtained. Compared with wild type, transgenic plants grew better under saline-alkali stress and the MhABF-OE lines showed higher chlorophyll content, POD, SOD and CAT activity, which indicated that they had strong resistance to stress. These results indicate that MhABF plays an important role in plant resistance to saline-alkali stress, which lays a foundation for further study on the functions in apple.
51 个 MdbZIP 基因通过生物信息学方法从苹果基因组中鉴定出来。MhABF-OE 提高了拟南芥对盐碱性胁迫的耐受性，表明其参与了盐碱性胁迫反应的正向调节。盐碱性胁迫是限制世界各地植物生长的主要非生物胁迫之一。bZIP 家族成员在调节基因表达方面发挥着重要作用，可响应多种生物和非生物胁迫，包括盐胁迫。根据转录组数据，在苹果基因组中鉴定出 51 个响应盐碱性胁迫的 MdbZIP 基因，分析了它们的基因结构、保守蛋白基序、系统进化分析、染色体定位和启动子顺式作用元件。基于转录组数据分析，选择并分离了一个在胁迫下高表达的 MdbZIP 家族基因（MD15G1081800），并将其命名为 MhABF。定量实时 PCR 表达谱分析证实，在胁迫后 2 天，MhABF 在山定子叶片中的表达量比对照（0 天）高 10.6 倍。然后从苹果砧木山定子中分离出 MhABF 基因。构建了 CaMV35S 启动子驱动的 MhABF 基因表达载体，通过农杆菌介导的侵染感染拟南芥。并获得了过表达 MhABF 基因的植株。与野生型相比，在盐碱性胁迫下，转基因植株生长状况更好，MhABF-OE 系的叶绿素含量、POD、SOD 和 CAT 活性更高，表明其具有较强的抗胁迫能力。这些结果表明，MhABF 在植物耐盐碱性胁迫中发挥着重要作用，为进一步研究苹果中的功能奠定了基础。
