红树植物抗重金属特性及其几丁质酶基因克隆与分析

以秋茄、白骨壤等红树植物为研究对象，开展在重金属胁迫下红树植物的膜脂质过氧化作用和体内活性氧清除系统中的保护酶的变化与影响研究，揭示逆境条件下红树植物的生理与生态特征；采用RACE和PCR技术，克隆红树植物I型和II型几丁质酶基因（chitinase genes，CG），通过NCBI的BLAST搜索和ClustalW比对，分析I型和II型几丁质酶基因结构；利用具有T7强启动子pET载体，将CG基因重组并转化到大肠杆菌BL21表达，进行了转化子抗重金属性能的研究该基因在红树植物抗重金属中的作用，利用实时定量PCR方法，探讨红树植物秋茄、白骨壤等I型和II型几丁质酶基因的表达与逆境存在的应答关系，揭示不同类型几丁质酶基因、不同重金属、不同组织之间的诱导表达模式，从分子水平上揭示红树植物抗重金属的生态学机理。

Mangroves are one of four high properties (high productivity and high return rate, high decomposition rate and high resistance) of typical and subtropical marine ecosystems, as well as unique wetland ecosystems in intertidal coastal regions of the tropics and subtropics, mainly distribute between latitudes 25° N and 25° S. The total area of mangrove forest in the world is about 1700,000 hectares, spanning 113 countries and territories. Mangroves play an important role in the functioning of tropical coastal ecosystems, and its total net primary productivity of mangroves is as high as 2000gC/m2/day. Mangroves play a key role in the maintenance and development of tropical and subtropical marine ecosystems, also play a very important role in the process of global environmental change. To reveal the physiological and ecological characteristics under heavy metals, the activity of antioxidative enzymes and lipid peroxidation were studied in mangrove plants of Kandelia obovata, Avicennia marina etc. Class I and II chitinase genes (CG) were cloned or characterized by rapid amplification of cDNA ends (RACE) and PCR amplification, and analyzed for their structures with BLAST and ClustalW. As well as their CG protein used the pET vector had expressed in E. coli BL21. The regulation patterns for mangroves will be different for the different metals tested, the different chitinase genes and different tissues. It will be investigated for chitinase genes of Kandelia obovata, Avicennia marina etc. in response to the pressure under heavy metal and also revealed for the molecular ecological mechanisms of mangrove plants adapting to heavy metals.