中国对虾血蓝蛋白基因cDNA的克隆与序列分析

利用3’和5’RACE技术从中国对虾Fenneropenaeus chinensis肝胰腺中克隆了1个血蓝蛋白基因FCHc,FCHc基因cDNA全长为2161bp。其中,开放阅读2 034bp,编码678个氨基酸,预测分子量为77.59 kDa。FCHc序列与凡纳滨对虾Litopenaeus vannamei血蓝蛋白同源性为82%,与日本囊虾Marsupenaeus japonicas同源性为85%。Real-timePCR实验结果表明,FCHc在肝胰腺中的相对表达量最高,在心脏和表皮中几乎不表达。该基因在鳗弧菌和对虾白斑综合征病毒(WSSV)感染后的对虾肝胰腺中的表达量显著增加,并具有不同的时空表达趋势,提示中国对虾FCHc基因在免疫反应中具有重要作用。     

Hemocyanin lipid uptake in Polybetes pythagoricus is altered by fenitrothion

The spider very high density lipoprotein (VHDL), which contains hemocyanin as the major apoprotein, transports most of the circulating lipids. In this work, the effect of the pesticide fenitrothion (FS) on the ability of VHDL-apoproteins to uptake different lipids was investigated. For this, VHDL was delipidated using Triton X-100 and recombined with different radiolabeled lipids in the presence or the absence of FS. The oligomeric structural integrity was maintained after delipidation as shown by non-denaturating PAGE. In the presence of the insecticide, palmitic acid uptake decreased by 28.2 and 62.4% after treating the apolipoprotein with 10 and 20 ppm FS, respectively. Decreases in the uptake of cholesterol, triolein, and phosphatidylcholine caused by FS were 29, 23, and 31% using 10 ppm, and 40, 44, and 29% using 20 ppm FS, respectively. Fluorescence measurements with the hydrophobic probes diphenylhexatriene (DPH) and diphenylhexatrienyl-propionic acid (DPH-PA) indicate that FS induces a red shift, decreases the intensity and increases the anisotropy of the emission of these probes in the VHDL. These results indicate that insecticide binding to the lipoprotein enhances the environment polarity and restricts the mobility of these probes at their binding site. These changes at the hydrophobic VHDL binding sites could lead to the decreased affinity for lipids and hydrophobic ligands. It is inferred that FS could alter the normal lipid exchange between this lipoprotein and tissues.     

野生克氏原螯虾的肌肉生化成分、组织消化酶和免疫酶活性分析

实验测定了两种规格(27.0±2.0、12.0±2.0 g)野生克氏原螯虾的肌肉生化成分、组织消化酶和免疫酶活性等.结果表明:大规格虾的肌肉能量以及整虾除肌肉外其它部分的能量均高于小规格虾,肌肉中天冬氨酸、谷氨酸和精氨酸的含量也均高于小规格虾;肝胰脏和肠道内蛋白酶、淀粉酶活力随pH值的增大均呈现先上升后下降的变化规律,...