Veelaert D, Devreese B, Schoofs L, Van Beeumen J, Vanden Broeck J, Tobe S S, De Loof A
Zoological Institute, Katholieke Universiteit Leuven, Belgium.
Mol Cell Endocrinol. 1996 Sep 18;122(2):183-90. doi: 10.1016/0303-7207(96)03889-0.
Eight myoinhibiting peptides were purified by high performance liquid chromatography from a methanolic extract of 7000 brains of the desert locust, Schistocerca gregaria. Complete sequences were obtained via a novel, combined approach employing: (1) chemical microsequencing and (2) post-source decay analysis on a reflectron time-of-flight mass spectrometer using matrix-assisted laser desorption/ionisation. Each of the peptides shows C-terminal amino acid sequence similarity to cockroach and cricket allatostatins and to blowfly callatostatins. Therefore, these novel peptides were designated Schistocerca gregaria allatostatins (Scg-ASTs) or schistostatins and their primary structures were determined to be: Ala-Tyr-Thr-Tyr-Val-Ser-Glu-Tyr-Lys-Arg-Leu-Pro-Val-Tyr-Asn-Phe-Gly-Leu- NH2 (Scg-AST-2), Ala-Thr-Gly-Ala-Ala-Ser-Leu-Tyr-Ser-Phe-Gly-Leu-NH2 (Scg-AST-3), Gly-Pro-Arg-Thr-Tyr-Ser-Phe-Gly-Leu-NH2 (Scg-AST-4), Gly-Arg-Leu-Tyr-Ser-Phe-Gly-Leu-NH2 (Scg-AST-5), Ala-Arg-Pro-Tyr-Ser-Phe-Gly-Leu-NH2 (Scg-AST-6), Ala-Gly-Pro-Ala-Pro-Ser-Arg-Leu-Tyr-Ser-Phe-Gly-Leu-NH2 (Scg-AST-7), Glu-Gly-Arg-Met-Tyr-Ser-Phe-Gly-Leu-NH2 (Scg-AST-8), and Ala-Pro-Ala-Glu-His-Arg-Phe-Ser-Phe-Gly-Leu-NH2 (Scg-AST-10). Synthetic Scg-AST peptides inhibit the peristaltic movements of the oviduct of S. gregaria. Although all eight peptides show potent inhibitory effects on juvenile hormone (JH) biosynthesis by corpora allata (CA) of the cockroach Diploptera punctata, no allatostatic effects were observed on CA of the desert locust (S. gregaria).
通过高效液相色谱法从7000只沙漠蝗虫（Schistocerca gregaria）的甲醇提取物中纯化出了8种肌抑制肽。通过一种新颖的组合方法获得了完整序列，该方法包括：（1）化学微量测序，以及（2）在反射式飞行时间质谱仪上使用基质辅助激光解吸/电离进行源后衰变分析。每种肽在C端氨基酸序列上与蟑螂和蟋蟀的咽侧体抑制素以及绿头苍蝇的咽侧体抑制素有相似性。因此，这些新型肽被命名为沙漠蝗虫咽侧体抑制素（Scg-ASTs）或蝗虫抑制素，其一级结构确定为：Ala-Tyr-Thr-Tyr-Val-Ser-Glu-Tyr-Lys-Arg-Leu-Pro-Val-Tyr-Asn-Phe-Gly-Leu-NH2（Scg-AST-2）、Ala-Thr-Gly-Ala-Ala-Ser-Leu-Tyr-Ser-Phe-Gly-Leu-NH2（Scg-AST-3）、Gly-Pro-Arg-Thr-Tyr-Ser-Phe-Gly-Leu-NH2（Scg-AST-4）、Gly-Arg-Leu-Tyr-Ser-Phe-Gly-Leu-NH2（Scg-AST-5）、Ala-Arg-Pro-Tyr-Ser-Phe-Gly-Leu-NH2（Scg-AST-6）、Ala-Gly-Pro-Ala-Pro-Ser-Arg-Leu-Tyr-Ser-Phe-Gly-Leu-NH2（Scg-AST-7）、Glu-Gly-Arg-Met-Tyr-Ser-Phe-Gly-Leu-NH2（Scg-AST-8）和Ala-Pro-Ala-Glu-His-Arg-Phe-Ser-Phe-Gly-Leu-NH2（Scg-AST-10）。合成的Scg-AST肽可抑制沙漠蝗虫输卵管的蠕动。尽管所有这8种肽对双斑大蠊咽侧体（CA）的保幼激素（JH）生物合成均显示出强效抑制作用，但对沙漠蝗虫（Schistocerca gregaria）的咽侧体未观察到咽侧体抑制作用。
