WAKE 通過神經內分泌軸調節特定嗅覺神經元影響雄果蠅同性間求偶行為

WAKE via a Hierarchical Neuro-Endocrine Axis Modulates the Specific Olfactory Sensory Neurons for Drosophila Male to Male Courtship Inhibition

周怡棋(Yi-Qi Chou)

指導教授 ： 傅在峰

國立暨南國際大學/科技學院/應用化學學系生物醫學碩士班/碩士(2021年)

https://doi.org/10.6837/ncnu202100014

摘要

神經與內分泌系統共同協調影響動物的行為。證據顯示胰島素製造細胞(insulin-producing cells; IPCs)中wake (wide awake)中失能會促使IPCs持續分泌類胰島素(insulin-like peptide; Ilps)，高量類胰島素/類胰島素生長因子訊號(insulin/insulin-like growth factor signaling; IIS)進入corpus allata (CA)進而促進青春激素(juvenile hormone, JH)生合成，同時也觀察到啟動蛻皮激素訊號的20-羥基蛻皮酮(20-hydroxyecdysone; 20E)水平降低。在本文中進一步確認上述受wake突變導致IIS、青春激素訊號與蛻皮激素訊號失衡影響接收雄性特有氣味11-cis vaccenyl acetate (cVA)的Or67d嗅覺感覺神經元誘發雄性同性間求偶行為。結果證實在Or67d嗅覺感覺神經元中提高胰島素訊號、青春激素訊號或是降低蛻皮激素訊號可以誘發雄性間同性求偶行為發生，進一步的在IPCs中下調WAKE或是wake突變雄蠅的背景下，在Or67d中抑制胰島素訊號、青春激素訊號或是提高蛻皮激素訊號可以降低原先的雄性間求偶行為，證實上述的內分泌訊號通過影響Or67d感覺神經元誘發同性間求偶行為；此外，在wake突變雄蠅或是IPCs中下調WAKE的背景下，在Or67d嗅覺感覺神經元上表現綠色螢光(GFP)或是Bruchpilot::GFP (Brp::GFP)並聚焦在DA1嗅小球觀察到與下游神經元projection neurons的連結能力明顯的變弱；通過鈣離子影像分析，在Or67d神經元表現GCaMP觀察到對cVA氣味的反應程度也顯著降低。

關鍵字

果蠅 ； WAKE ； 嗅覺感覺神經元 ； cVA ； 胰島素 ； 蛻皮激素 ； 青春激素 ； 同性間求偶行為

並列摘要

The coordination of the nervous and endocrine systems closely affects the behavioral response in animals. Evidence indicates that wake deficiency in insulin producing cells (IPCs) promotes the synthesis of juvenile hormones by corpus allata (CA) via insulin/insulin-like growth factor signalling (IIS) and reduces the level of ecdysone. Finally, it ultimately affects the olfactory sensory neurons in Drosophila melanogaster to induce male-male courtship behavior. This study further identifies the area of endocrines affected to the sensory neuron Or67d, which receives the male-specific odor cVA. The results showed that directly enhancing the insulin signal, JH signal or weakening the ecdysone signal in Or67d can induce inter-male courtship behavior; while IPCs down-regulate WAKE or under the background of wake mutation, after down-regulating the insulin signaling or JH signaling and up-regulating the ecdysone signaling in Or67d neurons, they can effectively inhibit the courtship behavior of male fruit flies. The courtship behavior between males is indeed caused by the influence of these endocrine message transmission pathways on Or67d. Furthermore, under the genetic background of wake mutation or IPCs down-regulation of WAKE, which observe the axon distribution of the olfactory sensory neuron in the DA1 olfactory glomerulus through GFP or Bruchpilot::GFP (Brp::GFP) expressed in Or67d neurons, the intensity or the connection relationship with downstream projection neurons (PNs) can be obviously weakened or reduced; and the degree of response of Or67d neurons to cVA through GCaMP analysis is also significantly reduced.

並列關鍵字

Drosophila ； WAKE ； OSNs ； cVA ； Insulin ； Ecdysone ； Juvenile Hormone ； Male-Male Courtship

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