日本研究人员10日在美国《神经元》杂志上报告说,他们发现了果蝇的求爱机制。如果能证实脊椎动物也有类似的机制,就有可能以此提高家畜等的繁殖效率。
雄性果蝇和雌性果蝇的脑神经细胞种类不同。日本东北大学教授山元大辅领导的研究小组发现,只有雄性果蝇拥有名为P1的神经细胞,这种细胞负责控制果蝇的求爱行动。雄性果蝇接触到雌性果蝇时,会感知到雌性果蝇身上的信息素,使P1细胞兴奋起来,从而发出求爱行动的指令。
研究人员向雄性果蝇的P1细胞中加入荧光物质,这种物质在神经细胞兴奋时就会发光。随后研究人员用针插入雄性果蝇的后背,将其固定住,然后让雌性果蝇靠近它们。结果发现只要雄性果蝇的足接触到雌性的身体,P1细胞就开始发光,雄性果蝇马上开始了包括扇动单侧翅膀在内的求爱行动。
研究小组认为,这说明雄性果蝇的足部拥有化学传感器,能够感知到雌性果蝇身上的信息素。他们表示,鱼类等脊椎动物也很可能通过特定的脑神经细胞发出采取求爱行动的指令,如果这一推测能够得到证实,养殖业就有望实现人工对动物的繁殖活动加以控制。(生物谷Bioon.com)
生物谷推荐原文出处:
Neuron DOI:10.1016/j.neuron.2010.12.017
Female Contact Activates Male-Specific Interneurons that Trigger Stereotypic Courtship Behavior in Drosophila
Soh Kohatsu, Masayuki Koganezawa, Daisuke Yamamoto
Highlights
Forcible activation of P1 or P2b fru-expressing neurons triggers male courtship
A tethered male initiates courtship when stimulated by a female contact
Tarsal contact with the female body causes a rapid Ca2+ rise in male P1 neurons
Transmidline P1 and descending P2b neurons compose a trigger system for courtship
Summary
We determined the cellular substrate for male courtship behavior by quasinatural and artificial stimulation of brain neurons. Activation of fruitless (fru)-expressing neurons via stimulation of thermosensitive dTrpA1 channels induced an entire series of courtship acts in male Drosophila placed alone without any courting target. By reducing the number of neurons expressing dTrpA1 by MARCM, we demonstrated that the initiation of courtship behavior is significantly correlated with the activation of the transmidline P1 interneurons, the descending P2b interneurons, or both, indicating that these interneurons trigger courtship. Using an experimental paradigm in which a tethered male can be stimulated to initiate courtship by touching his foreleg tarsus to a female's abdomen, we found that P1 neurites of tethered males showed a transient Ca2+ rise after tarsal stimulation with the female-associated sensory cues. These observations strongly suggest that P1 neurons are the prime components of the neural circuitry that initiates male courtship.