昆虫神经肽PBAN的细胞内信号转导

Intracellular signal transduction of insect neuropeptide PBAN

昆虫性信息素多数为长链的不饱和醇、醋酸酯、醛或酮类,链长一般为10-20碳,主要在性信息素腺体内由乙酰辅酶A经过脂肪酸合成、碳链缩短、去饱和以及碳酰基的还原修饰等步骤合成的;而性信息素合成激活肽(pheromone biosynthesis activating neuropeptide,PBAN)是由昆虫食管下神经节中的部分神经细胞合成和分泌的神经肽,通常由33个氨基酸组成,在C-末端有一个相同的五肽序列,主要调控性信息素的生物合成。有关PBAN的细胞内信号转导是近几年的研究热点,研究显示 PBAN首先与性信息素腺体细胞表面的G蛋白偶联受体结合,随后依据昆虫种类的不同,其细胞内信号转导方式主要有三种:(1)以cAMP信号传导途径进行信号转导;(2)以cAMP和磷脂酰肌醇信号传导途径共同进行信号转导;(3)主要以Ca2+为第二信使进行信号传导。

Insect sex pheromones are mainly constituted by C10-20 unsaturated acyclic aliphatic compounds with limited functional groups such as alcohol, acetate ester, aldehyde or ketone. They are synthesized in the pheromone gland from acetyl-CoA through fatty acid synthesis, chain-shortening, desaturation and reductive modification of the carbonyl carbon. Pheromone biosynthesis activating neuropeptide （PBAN） produced by neuroendocrine cells of the suboesophageal ganglion is a 33 amino acid neuropeptide which has a common C- terminal pentapeptide for pheromonotropic activity. In the past decade extensive studies were focused on the intracellular signal transduction of PBAN. PBAN acts firstly on pheromone gland cells of mature females by binding to a specific G-protein coupled membrane receptor, then one of three defferent pathways for intracellular signal transduction of PBAN is opened according to insect species. The three pathways are： 1. involvement of cAMP; 2. involvement of cAMP and phosphatidylinositol; 3. only involvement of Ca^2＋ as the second messenger.