BEHAVIORAL /HORMONAL REGULATION OF EXCITABLE MEMBRANES

我们已经开发了一个模型系统，用于探索动物的物理和社会环境的变化如何导致其可兴奋膜的重塑。硬骨鱼电鱼Brachyhypomus pinnicaudatus产生用于电定位和通信的电波形。波形的形状和幅度由离子电导和电器官中可兴奋膜的动力学决定。波形属性会逐渐（小时-天）和快速（分钟）变化。这两个时间进程是一致的基因组类固醇的行动和非基因组行动，分别为身份不明的激素工作，以修改兴奋膜的电器官。我们可以通过在实验室中操纵光线和社会条件来引起鱼的电波波形特性的变化。在所提出的项目中，我们将确定哪些激素产生我们在电波形中看到的快速和缓慢变化，并确定变化波形背后的离子机制。这个系统的一个优势是其生物相关性的范围;我们了解电波形变化的行为意义，因此通过确定细胞和分子机制，我们可以绘制一长串连续的因果关系，从社会行为到离子通道和第二信使系统的潜在基因调控。该项目的一个潜在好处是定位重要的新生物分子的可能性，包括性类固醇的膜受体。

We have developed a model system for exploring how changes in an animal's physical and social environment result in the remodeling of its excitable membranes. The teleost electric fish Brachyhypomus pinnicaudatus produces an electric waveform for electrolocation and communication. Shape and amplitude of the electric waveform are determined by ion conductance and kinetics of excitable membranes in the electric organ. Waveform properties change both gradually (hours- days) and quickly (minutes). These two time courses are consistent with genomic steroid action and a non-genomic action respectively of unidentified hormones working to modify the excitable membranes of the electric organ. We can elicit changes in the fish's electric waveform properties by manipulating light and social conditions in the lab. In the project proposed, we shall determine which hormones produce the rapid and slow changes we see in the electric waveform and identify the ionic mechanisms underlying the changing waveform. A strength of this system is the scope of its biological relevance; we understand the behavioral significance of the electric waveform changes, so by determining the cellular and molecular mechanisms, we can draw a long chain of continuous causal connections, from social behavior to the underlying gene regulation of ion channels and 2nd messenger systems. A potential benefit of this project is the possibility of localizing important new biomolecules including membrane receptors for sex steroids.