Determination of the Spontaneous Locomotor Activity in Drosophila melanogaster

Summary

Drosophila melanogaster are useful in studying genetic or environmental manipulations that affect behaviors such as spontaneous locomotor activity.  Here we describe a protocol that utilizes monitors with infrared beams and data analysis software to quantify spontaneous locomotor activity. 

Abstract

Drosophila melanogaster has been used as an excellent model organism to study environmental and genetic manipulations that affect behavior. One such behavior is spontaneous locomotor activity. Here we describe our protocol that utilizes Drosophila population monitors and a tracking system that allows continuous monitoring of the spontaneous locomotor activity of flies for several days at a time. This method is simple, reliable, and objective and can be used to examine the effects of aging, sex, changes in caloric content of food, addition of drugs, or genetic manipulations that mimic human diseases.

Introduction

Fruit flies, Drosophila melanogaster, have been used as a valuable model organism to study mechanisms underlying complex behaviors, such as learning and memory, social interaction, aggression, drug abuse, sleep, sensory function, courtship, and mating^1,2. One behavior that has been studied through multiple protocols is spontaneous locomotor activity. Negative geotaxis was one of the first methods developed for measuring Drosophila activity, and this protocol involves measuring the percentage of flies that reach a certain height of the vial after flies were shaken to the bottom of the container^1,3.  This method has advantage....

Protocol

Note: The Canton-S strain is the standard wild-type background line obtained from the Bloomington Stock Center.

1. Food Preparation and Recipe for 1,000 ml of Food

Note: This section describes the protocol for food preparation. Large metal pots are used to prepare about 18 L of food at a time. The protocol described here is downsized and uses 1,000 ml H₂O. Food is autoclaved twice.

1. Mix 113 g sucrose and 28 g brewers yeast in 643 ml water. Leave ingredients on a hot plate set at 25 °C with a stir bar to mix throughout for 15 minutes.
2. Autoclave food solution for 20 min.
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Results

The spontaneous locomotor activity in Drosophila depends on fly gender (Figure 3A), calorie content of the food (Figure 3B) and the light/dark cycle. Once the light is switched off fly activity dramatically decreases. Figure 3A illustrates 24 hours of locomotor activity recordings of male and female flies. An asterisk on the x-axis marks the time when the light was switched off and the transition to dark cycle. Figure 3B illustrates the standard.......

Discussion

Spontaneous locomotor activity of flies is influenced by many factors such as age, genetic background, and gender^2,13,18,19. In addition, environmental factors such as caloric content of the food, temperature of the environment, addition of different drugs, and day/night light cycle can affect fly activity. For instance, male flies of the same age have a higher spontaneous physical activity compared to females (Figure 1). Therefore, flies of the same age and gender should be compared to each o.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Sucrose FCC Food Grade 100 LB,	Fisher Scientific MP Biomedicals	ICN90471380
Brewer’s Yeast	Fisher Scientific MP Biomedicals	ICN90331280
Drosophila Agar Fine	SciMart	DR-820-25F
Cornmeal	Fisher Scientific MP Biomedicals	ICN90141125
Methyl4-hydroxybenzoate, tegosept	Sigma	H5501-5KG
EtOH	Pharmco-AAPER	111000200
Active Dry Yeast	Fisher Scientific	ICN10140001
Fly CO2 pad	LabScientific	BGSU-7
Stereo Microscope	Olympus	SZ40
Drosophila carbon dioxide (CO2) tank	Airgas	UN1013
Small paint brush for pushing the flies
Shell vial wide	Fischer Scientific	AS519
Buzzplugs for wide plastic vials	Fischer Scientific	AS275
Glass vials (25 x 95 mm)	Fischer Scientific Kimble 60931-8	AS-574
Sponge plugs for glass vials	SciMart	DR-750
Drosophila Food Dispenser	Applied Scientific (Fischer Scientific)	AS780Q
DPM Drosophila Population Monitor	Trikinetics Inc.
DC Power Supply with line cord	Trikinetics Inc.
PSIU9 The Power Supply Interface Unit	Trikinetics Inc.
Telephone cables and 5 way splitters	Trikinetics Inc.
Universal Serial Bus (USB) hardware	Trikinetics Inc.
Macintosh or Windows PC with UCB port
DAMSystem308X Data Acquisition Software for Macintoch OSX (Intel)	www.trikinetics.com
DAMSystem308 Data Acquisition Software for Windows PC (XP/Vista/7)	www.trikinetics.com
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DAMFileScan108X software for Macintosh	www.trikinetics.com
DAMFileScan108X software for Windows PC (XP/Vista/7)	www.trikinetics.com
USB software (PSIUdrivers.zip)	www.trikinetics.com
DAMSystem Notes 308	(http://www.trikinetics.com/Downloads/DAMSystem%20Notes%20308.pdf