感覺訊號對高度性慾所引發之果蠅雄性間求偶行為的影響

Reliance on External Sensory Cues for Male-Male Courtship Initiation in a High Sex Drive Drosophila Male

余昱緯(Yhu-Wei Yu)

指導教授 ： 傅在峰

國立暨南國際大學/科技學院/應用化學系生物醫學碩士班/碩士(2015年)

https://doi.org/10.6837/NCNU.2015.00265

摘要

多巴胺(Dopamine；DA)調控許多重要的生理與行為反應，包括對性慾(sexuality)的調控。本實驗團隊過去的研究發現，果蠅(Drosophila)大腦中的PPL2ab多巴胺神經元(dopaminergic PPL2ab neurons)參與調節雄性果蠅的求偶強度；而本論文也證實當PPL2ab神經元的多巴胺含量增加後也可以誘發雄果蠅產生動態訊號依賴(motion cue-dependent)的同性間求偶行為，但對雌性的性別選擇偏好(sexual preference)則未改變；有趣的是，如果將雄蠅大腦中的PPL2ab神經元多巴胺含量降低時，可能導致體表碳氫化合物(cuticular hydrocarbons; CHs)組成的改變，在剝奪視覺訊息的黑暗環境中仍可觀察到PPL2ab多巴胺含量增加的雄果蠅對其展開同性求偶行為。求偶行為是自然界中動物的一種本能，雄性透過求偶的行為達到交配、繁衍後代的目的，同性間求偶的行為並不常見，大腦中調控此行為的神經網絡目前仍未被清楚地釐清，本研究藉由控制雄果蠅大腦中的PPL2ab神經元的多巴胺含量即可操控雄果蠅同性間courter 與courtee的角色轉換，預期此結果將提供後續針對神經網絡與性反應相關研究上一個有趣的平台。

關鍵字

果蠅 ； 雄性間求偶行為 ； 多巴胺 ； PPL2ab神經元 ； 性費洛蒙

並列摘要

Dopamine (DA) regulated many physiological responses and behaviors. Scattered evidence has suggested that DA affects sexual desire in many species. In our previous findings imply PPL2ab neurons function to regulate male strength. Interesting, when we induced up-regulated DA levels in PPL2ab neurons, visual cues-dependent intermale courtship behavior was also observed significantly. However, in a detailed analysis of male courtship propensity female courtees, which implies the increased DA levels in PPL2ab neurons did not change male sexual orientation. Nevertheless, in dark environment to block the visual cues, when decreased DA level in PPL2ab neurons, other male Drosophila with increased DA level in PPL2ab neurons would be attracted for courtship behavior Our results indicate that PPL2ab neurons have played a critical role manipulating the courtship behavior between courtee and courter Drosophila. As such a complicated behavior could be simply controlled by this neurak circuitry, it is expected that outcome would become an effective platform for relevant research on homosexual behavior. Hope in the further that more molecular and anatomical insights gained from our extend work in Drosophila will be mirrored mammalian behavior, provide a model for studying the underlying mechanism and neuronal circuitry involved in the effect or sexuality.

並列關鍵字

Drosophila ； male-male courtship ； PPL2ab neurons ； dopamine ； sex pheromone

參考文獻

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