The Hillary Climber trumps manual testing: an automatic system for studying Drosophila climbing

Abstract

Climbing or negative geotaxis is an innate behavior of the fruit fly Drosophila melanogaster. There has been considerable interest in using this simple behavior to gain insights into the changes in brain function associated with aging, influence of drugs, mutated genes, and human neurological disorders. At present, most climbing tests are conducted manually and there is a lack of a simple and automatic device for repeatable and quantitative analysis of fly climbing behavior. Here we present an automatic fly climbing system, named the Hillary Climber (after Sir Edmund Hillary), that can replace the human manual tapping of vials with a mechanical tapping mechanism to provide more consistent force and reduce variability between the users and trials. Following tapping the HC records fly climbing, tracks the fly climbing path, and analyzes the velocity of individual flies and the percentage of successful climbers. The system is relatively simple to build, easy to operate, and efficient and reliable for climbing tests.

Keywords:

• Drosophila
• climbing
• automation
• geotaxis
• aging
• neurological disorders

Acknowledgements

This is an undergraduate honors research project and supported in part by the Life Sciences Undergraduate Research Opportunity Program (LS UROP) and Engineering Undergraduate Research Program at the University of Missouri (to AMW) and by a research grant from the National Science Foundation (NSF) (IOS-1354609 to BZ). We thank the members of the Zhang lab for discussions and support and the machine shop at the Bond Life Sciences Center at the University of Missouri for assisting us in the design and manufacture of the HC system. We also thank two anonymous reviewers for their helpful suggestions that have helped us improve the figures and text. This manuscript is part of the special issue honoring the lifetime achievements of Dr. Barry Ganetzky who recently retired from the University of Wisconsin-Madison. It is fitting to note that Barry was among the first persons to perform the fly climbing test (Ganetzky & Flanagan, 1978), and the method he developed was adopted later by many others, including the Zhang lab. BZ wishes to thank Barry for his mentorship, support, sense of humor, and friendship.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.