蚯蚓提取液对家蚕热激蛋白水平及免疫功能的影响

Effects of earthworm extract on heat shock protein levels and immune function of silkworm, Bombyx mori

为探讨蚯蚓提取液对家蚕热激蛋白的表达及免疫功能的影响,家蚕5龄幼虫饲喂蚯蚓提取液(50、100和200倍原液稀释)处理的桑叶,饲喂6 d后解剖获取家蚕中肠及血淋巴组织,利用实时荧光定量PCR检测中肠组织中HSP70和HSP90基因的表达;利用ELISA试剂盒检测中肠和血淋巴中HSP70、HSP90、溶菌酶(lysozyme)和抗菌肽(attacin)的水平。结果表明:1/100和1/200稀释组家蚕中肠组织中HSP70基因表达分别是对照组的2.97和1.86倍(P<0.05),1/100稀释组家蚕中肠组织中HSP90基因表达是对照组的2.2倍(P<0.05);1/50稀释组中肠HSP70和血淋巴抗菌肽显著高于对照组(P<0.05);各处理组中肠和血淋巴中HSP90差异不显著(P>0.05)。由此可见,桑叶中添食蚯蚓提取液可促进热激蛋白的表达,提高抗菌肽的水平,进而提高蚕体的抗性和免疫功能。

To investigate the effect of earthworm extract on the expression of heat shock protein and immune function of silkworm, Bombyx mori, the fifth instar larvae of silkworm were fed with mulberry leaves to which one of three diluted does(1/50, 1/100 and 1/200) earthworm extract had been added. The midgut and hemolymph were obtained after feeding for six days, the expression of HSP70 and HSP90 in midgut were analyzed by quantitative real-time PCR and the levels of HSP70, HSP90, lysozyme and attacin in the midgut and hemolymph were tested by the ELISA kit. The results showed that, the expression of HSP70 gene in the midgut tissues of the 1/100 and 1/200 dilution groups was 2.97 and 1.86 times of the control group, respectively(P<0.05). The expression of HSP90 gene in the midgut tissues of the 1/100 dilution group was 2.2 times of the control group(P<0.05). The HSP70 and hemolymph peptides in the 1/50 dilution group were significantly higher than those in the control group(P<0.05). There was no significant difference in HSP90 between intestine and hemolymph in each treatment group(P>0.05).Thus, adding the earthworm extract in mulberry leaves can promote the expression of heat shock protein, increase the level of atticin, and improve the resistance and immunity of silkworm.