Mechanisms of toxicity of anti-insect proteins from latex of mulberry trees known as a host plant of silkworms.

为了阐明mlx基因应用的可能性，将编码桑葚抗虫蛋白的mlx56基因导入拟南芥。mlx56基因在叶片中的表达在转录水平上观察到，然而，MLX56蛋白不能通过免疫印迹分析检测到，并且没有观察到对蓖麻蚕和甘蓝蛾幼虫的毒性。MLX56结合在蓖麻蚕幼虫围食膜的整个部分，而观察到对蚕幼虫的几乎没有结合性质。结果表明，MLX56的靶位点是围食膜，家蚕幼虫通过与MLX56形成低亲和力的围食膜来逃避MLX56。

A mlx56 gene encoding mulberry anti-insect protein was introduced into Arabidopsis thaliana in order to elucidate the possibility of application use of a mlx gene. The expression of mlx56 gene in leaves was observed at a transcription level, however, the MLX56 protein could not be detected by immunoblot analysis, and no toxicity was observed against larvae of the Eri-silkworms and the cabbage moth. The MLX56 bind at entire part of peritrophic membrane of larvae of the Eri-silkworm whereas little binding property was observed against that of larvae of the silkworm. The results strongly suggested that the target site of the MLX56 is the peritrophic membrane, and larvae of the silkworm circumvent from the MLX56 by developing low-affinity peritrophic membrane with the MLX56.