大黄粉虫幼虫体内黑色素合成相关蛋白的鉴定

Identification of melanization-associated proteins in Tenebrio molitor larvae

目的鉴定大黄粉虫幼虫体内与酚氧化酶（PO）诱导的黑色素合成相关的蛋白（MAPs）。方法体外诱导大黄粉虫幼虫血淋巴中黑色素合成反应，对上清液中的蛋白质进行SDS-PAGE分析，比较黑色素合成前后、合成过程中及在苯硫脲存在下蛋白质的变化，对黑色素合成过程中消失的蛋白进行氨基端氨基酸序列分析。结果6条蛋白带（MAP-1～6）呈时间依赖性地从黑色素合成反应的上清液中消失。苯硫脲可阻断此反应而取消蛋白的消失；氨基端氨基酸序列分析表明MAP-1，2为已知的大黄粉虫卵黄素样蛋白，MAP-3，4，5为未知蛋白，MAP-6为已知的大黄粉虫干燥蛋白。结论大黄粉虫幼虫血淋巴中至少5种蛋白与PO诱导的黑色素合成反应特异性相关。

Objective To identify the proteins associated with PO-induced melanin synthesis （MAPs） in Tenebrio molitor larvae. Methods The melanin synthesis of G-100 solution was induced by β-1,3-D-glucan and Ca2 ＋ in the presence of dopamine in vitro. The proteins in the supernatant of the reaction mixture were analyzed by 12 % SDS-PAGE electrophoresis. The amino-terminal amino acid sequences of the proteins disappeared during the PO-induced melanin synthesis were determined. Results Six proteins disappeared from the supernatant of the melanization reaction mixture in a time-dependent manner. In the presence of PTU, an inhibitor of PO activity, the six bands did not disappear. The amino-terminal sequence analysis showed that both MAP-1 and 2 were the vitellogenin-like protein of T. molitor. The MAP-3, 4 and 5 were unknown proteins. The MAP-6 was the desiccation protein of T. molitor. Conclusions At least 5 proteins are specially associated with PO-induced melanin synthesis in T. molitor larvae.