College of Plant Protection, Henan Agricultural University, Zhengzhou, People's Republic of China.
PLoS One. 2012;7(2):e31045. doi: 10.1371/journal.pone.0031045. Epub 2012 Feb 16.
Pheromone biosynthesis activating neuropeptide (PBAN) is a neurohormone that regulates sex pheromone synthesis in female moths. Bombyx mori is a model organism that has been used to explore the signal transduction pattern of PBAN, which is mediated by a G-protein coupled receptor (GPCR). Although significant progress has been made in elucidating PBAN-regulated lipolysis that releases the precursor of the sex pheromone, little is known about the molecular components involved in this step. To better elucidate the molecular mechanisms of PBAN-stimulated lipolysis of cytoplasmic lipid droplets (LDs), the associated lipase genes involved in PBAN- regulated sex pheromone biosynthesis were identified using digital gene expression (DGE) and subsequent RNA interference (RNAi).
Three DGE libraries were constructed from pheromone glands (PGs) at different developed stages, namely, 72 hours before eclosion (-72 h), new emergence (0 h) and 72 h after eclosion (72 h), to investigate the gene expression profiles during PG development. The DGE evaluated over 5.6 million clean tags in each PG sample and revealed numerous genes that were differentially expressed at these stages. Most importantly, seven lipases were found to be richly expressed during the key stage of sex pheromone synthesis and release (new emergence). RNAi-mediated knockdown confirmed for the first time that four of these seven lipases play important roles in sex pheromone synthesis.
This study has identified four lipases directly involved in PBAN-stimulated sex pheromone biosynthesis, which improve our understanding of the lipases involved in releasing bombykol precursors from triacylglycerols (TAGs) within the cytoplasmic LDs.
信息素生物合成激活神经肽（PBAN）是一种神经激素，它调节雌性飞蛾的性信息素合成。家蚕是一种模式生物，用于探索 PBAN 的信号转导模式，该模式由 G 蛋白偶联受体（GPCR）介导。尽管已经在阐明 PBAN 调节脂解方面取得了重大进展，脂解释放性信息素的前体，但对于涉及该步骤的分子成分知之甚少。为了更好地阐明 PBAN 刺激细胞质脂滴（LDs）脂解的分子机制，涉及 PBAN 调节性信息素生物合成的相关脂肪酶基因通过数字基因表达（DGE）和随后的 RNA 干扰（RNAi）进行鉴定。
从不同发育阶段的性腺体（PGs）构建了三个 DGE 文库，分别为出茧前 72 小时（-72 h）、新出现（0 h）和出茧后 72 小时（72 h），以研究 PG 发育过程中的基因表达谱。每个 PG 样本中的 DGE 评估超过 560 万个清洁标签，并揭示了在这些阶段差异表达的许多基因。最重要的是，在性信息素合成和释放的关键阶段（新出现）发现了七种富含脂肪酶。RNAi 介导的敲低首次证实，这七种脂肪酶中的四种在性信息素合成中发挥重要作用。
本研究鉴定了直接参与 PBAN 刺激的性信息素生物合成的四种脂肪酶，这提高了我们对参与从细胞质 LDs 中的三酰基甘油（TAGs）释放 bombykol 前体的脂肪酶的理解。
