Department of Biological Sciences, University of Cape Town, Cape Town, South Africa.
Biology Centre, Czech Academy of Sciences, České Budĕjovice, Czech Republic.
Arch Insect Biochem Physiol. 2021 Apr;106(4):e21778. doi: 10.1002/arch.21778. Epub 2021 Mar 15.
One representative of the order Trichoptera, namely the caddisfly Chaetopteryx villosa, was investigated along with the pygmy mole cricket Xya capensis which is a representative of the most basal superfamily of the caeliferan Orthoptera, that is, the Tridactyloidea. From both clades neuropeptides have not been biochemically characterized before this study. Here, members of the adipokinetic hormone family (AKHs) are sequenced via liquid chromatography (LC)-ion trap mass spectrometry from methanolic extracts from the corpora cardiaca of respective species. The corpora cardiaca were dissected, methanolic extracts prepared, peptides separated by liquid chromatography (LC), and AKHs detected and sequenced by ion trap mass spectrometry. Both species investigated contain an octapeptide AKH: the trichopteran species has the peptide with the sequence pGlu-Leu-Thr-Phe-Thr-Pro-Ser-Trp amide; the ambiguity of the isobaric amino acids Leu and Ile at position two was solved by comparing retention times on LC and by co-elution with the synthetic Leu -form. This peptide is known as Aedae-AKH and found in certain dipteran species and in an alderfly (Megaloptera). The tridactyloid species contains the peptide with the sequence pGlu-Val-Asn-Phe-Ser-Pro-Gly-Trp amide which had first been identified in a member of the order Mantophasmatodea and is called Manto-CC. Comparisons are made between the AKH complements of the sister groups Trichoptera and Lepidoptera and their possible relatedness and, on the other hand, between the AKH of X. capensis with those of closely related caeliferan superfamilies. The biology of the two studied species is used to speculate about a possible function of the elucidated hormones. Lastly, the use of a larval stage as starting material for structural neuropeptide information is discussed.
研究了一个毛翅目（Trichoptera）代表，即束毛翅石蛾（Chaetopteryx villosa），以及最基础的直翅目（Orthoptera）超科原尾目（Caelifera）的代表小蝼蛄（Xya capensis）。在这项研究之前，这两个进化枝的神经肽都没有进行过生化特性分析。本研究通过液相色谱（LC）-离子阱质谱法，从各自物种的心侧体甲醇提取物中对类脂酮激素家族（AKHs）成员进行了测序。心侧体被解剖，甲醇提取物被制备，肽通过液相色谱（LC）分离，AKHs 通过离子阱质谱法检测和测序。所研究的两个物种都含有一个八肽 AKH：毛翅目物种的肽序列为 pGlu-Leu-Thr-Phe-Thr-Pro-Ser-Trp amide；位置 2 上的等电氨基酸亮氨酸和异亮氨酸的不明确性通过比较 LC 上的保留时间和与合成亮氨酸形式的共洗脱来解决。这种肽被称为 Aedae-AKH，在某些双翅目物种和蜻蜓目（Megaloptera）中发现。原尾目物种含有肽序列 pGlu-Val-Asn-Phe-Ser-Pro-Gly-Trp amide，该肽最初在 Mantophasmatodea 目成员中被鉴定出来，称为 Manto-CC。比较了姐妹群毛翅目和鳞翅目 AKH 补充的可能相关性，以及另一方面，比较了 X. capensis 的 AKH 与密切相关的直翅目超科的 AKH。利用两种研究物种的生物学知识，推测了阐明的激素的可能功能。最后，讨论了使用幼虫阶段作为结构神经肽信息的起始材料的问题。
