2017.03.21 Oregon Health & Science University 马志国博士学术报告会
报告人：马志国博士，Vollum Institute, Oregon Health & Science University 时间：2017年3月21日上午10:00 地点：生命科学楼531会议室
报告题目：Neuromodulators Signal Through Astrocytes to Alter Neural Circuit Activity and Behavior
摘要： Astrocytic calcium (Ca2+) signaling has been proposed to modulate neural circuit activity, but the pathways that regulate these events are poorly defined and in vivoevidence linking changes in astrocyte Ca2+levels to alterations in neurotransmission or behavior is limited. Here we show that Drosophilaastrocytes exhibit activity-regulated Ca2+signaling in vivo. Tyramine and octopamine released from neurons expressing tyrosine decarboxylase 2 (Tdc2) signal directly to astrocytes to stimulate Ca2+increases through the octopamine/tyramine receptor (Oct-TyrR) and the transient receptor potential (TRP) channel Water witch (Wtrw), and astrocytes in turn modulate downstream dopaminergic neurons. Application of tyramine or octopamine to live preparations silenced dopaminergic neurons and this inhibition required astrocytic Oct-TyrR and Wtrw. Increasing astrocyte Ca2+signaling was sufficient to silence dopaminergic neuron activity, which was mediated by astrocyte endocytic function and adenosine receptors. Selective disruption of Oct-TyrR or Wtrw expression in astrocytes blocked astrocytic Ca2+signaling and profoundly altered olfactory-driven chemotaxis and touch-induced startle responses. Our work identifies Oct-TyrR and Wtrw as key components of the astrocytic Ca2+signaling machinery, provides direct evidence that octopamine- and tyramine-based neuromodulation can be mediated by astrocytes, and demonstrates that astrocytes are essential for multiple sensory-driven behaviors in Drosophila.
报告人简介： 马志国博士本科毕业于安徽医科大学，博士毕业于中科院遗传与发育研究所。其后分别在University of Massachusetts Medical School和Oregon Health & Science University从事研究工作。