Identification of a novel gene encoding the trehalose phosphate synthase in the cotton bollworm, Helicoverpa armigera
Identification of a novel gene encoding the trehalose phosphate synthase in the cotton bollworm, Helicoverpa armigera
复制标题
棉铃虫 Helicoverpa armigera 中编码磷酸海藻糖合酶的新基因的鉴定。
DOI：
10.1093/glycob/cwn127
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发表时间：
2009-03-01
期刊：
影响因子：
4.3
通讯作者：
Xu, Wei-Hua
中科院分区：
文献类型：
--
作者：
Xu, Jun;Bao, Bin;Xu, Wei-Hua
海藻糖和海藻糖代谢对昆虫的发育至关重要。测定了棉铃虫滞育个体和非滞育个体血淋巴中多羟基化合物的含量。结果表明，滞育个体的海藻糖含量明显高于非滞育个体。研究了H.滞育型个体的棉铃虫幼虫-蛹发育显著更高，并且与海藻糖含量的变化密切相关。从嗜热链球菌的脂肪体中克隆了编码TPS的cDNA，该TPS可将尿苷-5 ′-二磷酸葡萄糖和葡萄糖-6-磷酸转化为海藻糖-6-磷酸。利用cDNA末端快速扩增（RACE）技术对棉铃虫的DNA序列进行扩增。cDNA的分子表征显示，mRNA编码826个氨基酸残基的前体多肽，在残基6-507处含有Har-TPS，在残基512-783处含有推定的海藻糖-6-磷酸磷酸酶，其将海藻糖-6-磷酸转化为游离海藻糖。Har-TPS前体多肽与果蝇的前体多肽具有73%的同源性。用北方印迹法检测到脂肪体和卵巢中存在2.8 kb的转录物。Har-TPS mRNA在6龄后期和滞育蛹的中早期表达量较高，这可能是对血淋巴中TPS活性和海藻糖变化的响应。Har-TPS蛋白在家蚕杆状病毒表达系统中成功过表达，在B中的催化活性提高了约5倍。重组杆状病毒感染的家蚕血液中的蛋白质含量高于对照。滞育解除后，海藻糖含量显著下降，葡萄糖含量迅速增加。这些结果表明，海藻糖参与调节H。棉铃虫蛹滞育
Trehalose and trehalose metabolism are crucial for insect development. We measured the content of polyhydric compounds in the hemolymph of diapause- and nondiapause-destined individuals of Helicoverpa armigera. We found that the trehalose content is much higher in diapause-destined individuals than that in nondiapause individuals. The activity of trehalose-6-phosphate synthase (TPS) during H. armigera larval-pupal development is significantly higher in diapause-type individuals and is closely correlated with the changes in the trehalose content. The cDNA encoding TPS, which converts uridine-5'-diphosphoglucose and glucose-6-phosphate to trehalose-6-phosphate, was cloned from the fat body of H. armigera using rapid amplification of cDNA ends (RACE). The molecular characterization of the cDNA revealed that the mRNA encodes a precursor polypeptide of 826-amino-acid residues, containing Har-TPS at residues 6-507 and a putative trehalose-6-phosphate phosphatase, which converts trehalose-6-phosphate into free trehalose, at residues 512-783. The Har-TPS precursor polypeptide shows 73% identity with that of Drosophila melanogaster. The presence of a 2.8 kb transcript in the fat body and ovary was detected with a northern blot. The Har-TPS mRNA was detected at high levels in the late stage of sixth larval instar and the early middle stage of diapause-destined pupae, which are most likely to respond the changes in TPS activity and trehalose in the hemolymph. The Har-TPS protein was successfully overexpressed in the Bombyx mori baculovirus expression system, and the catalytic activity of Har-TPS was found to be approximately 5-fold higher in B. mori blood infected by the recombined-baculovirus than the control. When diapause is broken, the trehalose content drops significantly and glucose increases rapidly. These results suggest that trehalose is involved in regulating H. armigera pupal diapause.