小麦几丁质酶基因的异种表达及其功能鉴定

几丁质酶参与植物的发育及防卫反应,并与人类疾病发生有关.文章研究了小麦几丁质酶基因Wch2经根癌农杆菌介导的烟草瞬间表达和转基因拟南芥的稳定表达,Western杂交及酶活测定证实,瞬间表达的小麦几丁质酶分子量约30 kD,具有降解几丁质多聚物的功能;Wch2在转入拟南芥后表达量高,尖孢镰刀菌接种的鉴定表明,表达Wch2的转基因植株的抗病性显著高于表达绿色荧光蛋白的对照植株.这些结果说明Wch2的异种表达,可用于植物抗病基因工程,以增强植物的抗病性.

Heterologous Expression and Functional Identification of a Chitinase Gene from Wheat

Chitinases are functional in plant defense against pathogens and also involved in plant devel- opment as well as human disease responses. In this study a chitinase gene, Wch2, from wheat was ex- pressed transiently in tobacco leaves and stably in transgenic Arabidopsis thaliana plants to evaluate its heterologous expression and potential application. Western blot analysis revealed that the expressed wheat chitinase was about 30 kD as was expected (Fig.1) and had hydrolytic activity towards chitin polymers (Fig.2). Integration and expression of Wch2 gene in transgenic Arabidopsis were con- firmed by PCR (Fig.3) and Western blot (Fig.4) analyses. Wch2 accumulated to a high level in transgenic plants without any detectable degradation. Transgenic plants expressing Wch2 displayed a much higher resistance to Fusarium oxysporum f. sp. matthiolae, a fungus infectious to Arabidopsisthaliana than the plants containing green fluores- cence protein (GFP) (Fig.5). These results indicated that Wch2 was suitable for heterologous expres- sion in different organisms and could be used for enhancement of plant resistance in genetic engineering. The Arabidopsis-Fusarium interaction may be one of the ideal plant-fungus interaction sys- tems for the evaluation of antifungal proteins in planta.