期刊
BMC PLANT BIOLOGY
卷 14, 期 -, 页码 -出版社
BMC
DOI: 10.1186/s12870-014-0208-4
关键词
Manihot esculenta Crantz; Cytosolic superoxide dismutase; Cytosolic ascorbate peroxidase; Reactive oxygen species scavenging; Abiotic stress resistance
资金
- National Basic Research Program [2010CB126605]
- National Natural Science Foundation of China [31271775]
- National High Technology Research and Development Program of China [2012AA101204]
- SIPPE-SCBG Joint Fund
- Earmarked Fund for China Agriculture Research System [CARS-12]
- Shanghai Municipal Afforestation & City Appearance and Environmental Sanitation Administration [G102410, F132427]
Background: Cassava (Manihot esculenta Crantz) is a tropical root crop, and is therefore, extremely sensitive to low temperature; its antioxidative response is pivotal for its survival under stress. Timely turnover of reactive oxygen species (ROS) in plant cells generated by chilling-induced oxidative damages, and scavenging can be achieved by non-enzymatic and enzymatic reactions in order to maintain ROS homeostasis. Results: Transgenic cassava plants that co-express cytosolic superoxide dismutase (SOD), MeCu/ZnSOD, and ascorbate peroxidase (APX), MeAPX2, were produced and tested for tolerance against oxidative and chilling stresses. The up-regulation of MeCu/ZnSOD and MeAPX2 expression was confirmed by the quantitative reverse transcriptase-polymerase chain reaction, and enzymatic activity analyses in the leaves of transgenic cassava plant lines with a single-transgene integration site. Upon exposure to ROS-generating agents, 100 mu M ROS-generating reagent methyl viologen and 0.5 M H2O2, higher levels of enzymatic activities of SOD and APX were detected in transgenic plants than the wild type. Consequently, the oxidative stress parameters, such as lipid peroxidation, chlorophyll degradation and H2O2 synthesis, were lower in the transgenic lines than the wild type. Tolerance to chilling stress at 4 C for 2 d was greater in transgenic cassava, as observed by the higher levels of SOD, catalase, and ascorbate-glutathione cycle enzymes (e.g., APX, monodehydroascorbate reductase, dehydroascorbate reducatase and glutathione reductase) and lower levels of malondialdehyde content. Conclusions: These results suggest that the expression of native cytosolic SOD and APX simultaneously activated the antioxidative defense mechanisms via cyclic ROS scavenging, thereby improving its tolerance to cold stress.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据