Choi Man-Yeon, Raina Ashok, Vander Meer Robert K
Center of Medical, Agricultural and Veterinary Entomology, United States Department of Agriculture-Agriculture Research Service, 1600 SW 23rd Drive, Gainesville, FL 32608, USA.
Cell Tissue Res. 2009 Feb;335(2):431-9. doi: 10.1007/s00441-008-0721-6. Epub 2008 Nov 11.
The pyrokinin/pheromone-biosynthesis-activating neuropeptide (PBAN) family of peptides found in insects is characterized by a 5-amino-acid C-terminal sequence, FXPRLamide. The pentapeptide is the active core required for diverse physiological functions, including the stimulation of pheromone biosynthesis in female moths, muscle contraction, induction of embryonic diapause, melanization, acceleration of puparium formation, and termination of pupal diapause. We have used immunocytochemical techniques to demonstrate the presence of pyrokinin/PBAN-like peptides in the central nervous system of the fire ant, Solenopsis invicta. Polyclonal antisera against the C-terminal end of PBAN have revealed the location of the peptide-producing cell bodies and axons in the central nervous system. Immunoreactive material is detectable in at least three groups of neurons in the subesophageal ganglion and corpora cardiaca of all adult sexual forms. The ventral nerve cord of adults consists of two segmented thoracic ganglia and four segmented abdominal ganglia. Two immunoreactive pairs of neurons are present in the thoracic ganglia, and three neuron pairs in each of the first three abdominal ganglia. The terminal abdominal ganglion has no immunoreactive neurons. PBAN immunoreactive material found in abdominal neurons appears to be projected to perisympathetic organs connected to the abdominal ganglia. These results indicate that the fire ant nervous system contains pyrokinin/PBAN-like peptides, and that these peptides are released into the hemolymph. In support of our immunocytochemical results, significant pheromonotropic activity is found in fire ant brain-subesophageal ganglion extracts from all adult fire ant forms (queens, female and male alates, and workers) when extracts are injected into decapitated females of Helicoverpa zea. This is the first demonstration of the presence of pyrokinin/PBAN-like peptides and pheromonotropic activity in an ant species.
在昆虫中发现的促速激肽/信息素生物合成激活神经肽（PBAN）家族的肽类，其特征在于具有一个5氨基酸的C末端序列FXPRLamide。该五肽是多种生理功能所需的活性核心，包括刺激雌蛾的信息素生物合成、肌肉收缩、诱导胚胎滞育、黑化、加速蛹形成以及终止蛹滞育。我们已使用免疫细胞化学技术来证明在火蚁（红火蚁）的中枢神经系统中存在促速激肽/PBAN样肽。针对PBAN C末端的多克隆抗血清已揭示了肽产生细胞体和轴突在中枢神经系统中的位置。在所有成年有性形态的咽下神经节和心侧体的至少三组神经元中可检测到免疫反应性物质。成年火蚁的腹神经索由两个分节的胸神经节和四个分节的腹神经节组成。胸神经节中有两对免疫反应性神经元，前三腹神经节中各有三对神经元。末腹神经节没有免疫反应性神经元。在腹神经节神经元中发现的PBAN免疫反应性物质似乎投射到与腹神经节相连的交感周缘器官。这些结果表明，火蚁神经系统含有促速激肽/PBAN样肽，并且这些肽会释放到血淋巴中。为支持我们的免疫细胞化学结果，当将来自所有成年火蚁形态（蚁后、雌性和雄性有翅蚁以及工蚁）的火蚁脑 - 咽下神经节提取物注射到被斩首的烟芽夜蛾雌性体内时，在提取物中发现了显著的促信息素活性。这是首次在蚁类中证明存在促速激肽/PBAN样肽和促信息素活性。
