Köblös Gabriella, Dankó Tamás, Sipos Kitti, Geiger Ágnes, Szlanka Tamás, Fodor József, Fónagy Adrien
Department of Pathophysiology, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Herman Ottó út 15, H-1022 Budapest, Hungary.
Ecotoxicology and Environmental Analysis Group, Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Herman Ottó út 15, H-1022 Budapest, Hungary.
Gen Comp Endocrinol. 2015 Sep 15;221:217-27. doi: 10.1016/j.ygcen.2015.03.004. Epub 2015 Mar 18.
Cabbage moth (Mamestra brassicae) females produce sex pheromones to attract conspecific males. In our M. brassicae colony, the pheromone blend is composed of Z11-hexadecenyl acetate (Z11-16Ac) and hexadecyl acetate (16Ac) in a 93:7 ratio. A fatty acyl Δ11-desaturase is involved in the production of the main pheromone component. The release of Pheromone Biosynthesis Activating Neuropeptide (PBAN) regulates the pheromone production in the pheromone gland (PG). We cloned a cDNA encoding the MambrΔ11-desaturase and analyzed its expression profile over time in M. brassicae tissues. Transcript levels of the Δ11-desaturase in larvae, pupal PGs, fat body, brain and muscle tissues were <0.1% of that in female PGs, whereas expression in male genitalia was 2%. In the PGs of virgin females the expression level increased continuously from eclosion to the end of the 1st day when it reached a plateau without further significant fluctuation up to the 8th day. In contrast, we recorded a characteristic daily rhythmicity in pheromone production with a maximum around 200 ng Z11-16Ac/PG. In some experiments, females were decapitated to prevent PBAN release and thereby inhibit pheromone production, which remarkably increased after treatment with Mambr-Pheromonotropin. Further experiments revealed that mating resulted in a significant suppression of pheromone production. However, expression of the Δ11-desaturase was not affected by any of these interventions, suggesting that it's not regulated by PBAN. Fluorescent microscopy was used to study the potential role of lipid droplets during pheromone production, however, no lipid droplets were identified indicating that pheromonogenesis is regulated via de novo fatty acid synthesis.
小菜蛾（甘蓝夜蛾）雌蛾会产生性信息素以吸引同种雄蛾。在我们的小菜蛾种群中，性信息素混合物由乙酸Z11 - 十六碳烯酯（Z11 - 16Ac）和乙酸十六酯（16Ac）按93:7的比例组成。一种脂肪酰基Δ11 - 去饱和酶参与主要性信息素成分的合成。信息素生物合成激活神经肽（PBAN）的释放调节性信息素腺（PG）中的信息素合成。我们克隆了一个编码MambrΔ11 - 去饱和酶的cDNA，并分析了其在小菜蛾组织中的表达谱随时间的变化。Δ11 - 去饱和酶在幼虫、蛹期PG、脂肪体、脑和肌肉组织中的转录水平仅为雌蛾PG中的<0.1%，而在雄蛾生殖器中的表达为2%。在未交配雌蛾的PG中，表达水平从羽化到第1天结束时持续增加，在第1天达到平台期，直至第8天无进一步显著波动。相比之下，我们记录到信息素产生具有特征性的每日节律性，最大值约为200 ng Z11 - 16Ac/PG。在一些实验中，对雌蛾进行断头处理以阻止PBAN释放，从而抑制信息素产生，而在用Mambr - 促信息素处理后，信息素产生显著增加。进一步实验表明交配会导致信息素产生显著抑制。然而，Δ11 - 去饱和酶的表达不受这些干预措施的影响，这表明它不受PBAN调节。使用荧光显微镜研究脂滴在信息素产生过程中的潜在作用，但未发现脂滴，这表明信息素生成是通过从头脂肪酸合成来调节的。
