Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Tokyo, Japan.
Laboratory of Cellular Neurobiology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan.
Neurosci Lett. 2014 Jun 6;570:10-5. doi: 10.1016/j.neulet.2014.04.011. Epub 2014 Apr 18.
Animals collect and integrate information from their environment, and select an appropriate strategy to elicit a behavioral response. Here, we investigate the behavioral strategy employed by Drosophila larvae during chemotaxis toward a food source functioning as an attractive odor source. In larvae, sharp turns have been identified as the main strategy during locomotion to odorant sources, but the existence of runs orienting toward the direction of higher odor concentrations has not been described. In this study, we show the existence of such a successive orientation toward an odor source, which we term as biased running. Our behavioral analysis, which examines the relationship between larval rotational velocities and larval positions relative to an attractive odor source, brings out this newly found behavioral strategy. Additionally, theoretically estimated concentration gradients of chemoattractants between left and right olfactory organs were statistically correlated with rotational velocities during biased running. Finally, computer simulations demonstrated that biased running enhances navigation accuracy. Taken together, biased running is an effective behavioral strategy during chemotaxis, and this notion may provide a new insight on how animals can efficiently approach the odor source.
动物从环境中收集和整合信息，并选择适当的策略来引发行为反应。在这里，我们研究了果蝇幼虫在向作为有吸引力气味源的食物源进行趋化性时所采用的行为策略。在幼虫中，急转弯已被确定为向气味源运动的主要策略，但尚未描述朝向更高气味浓度方向的奔跑的存在。在这项研究中，我们展示了这种对气味源的连续定向的存在，我们称之为偏置奔跑。我们的行为分析检查了幼虫旋转速度与相对于有吸引力的气味源的幼虫位置之间的关系，从而揭示了这种新发现的行为策略。此外，理论上估计的左右嗅觉器官之间的化学引诱剂浓度梯度与偏置奔跑期间的旋转速度呈统计学相关。最后，计算机模拟表明，偏置奔跑可提高导航精度。总之，偏置奔跑是趋化性过程中的一种有效行为策略，这一概念可能为动物如何有效地接近气味源提供新的见解。
