Description

The MazeEngineers Drosophila Array allows for one of a kind Drosophila experiments. Based on the work done by De Bivort et al, the arrays allow for a few key features:

• Multiple arrays with a backlight allow for precise video tracking of multiple Drosophila at once
• Precision made arrays allow individual drosophila to run unique experiments. Each array is well lit using this configuration
• Multiple arrays possible including Y, T, +, and -.
• Customized array shapes possible as well. Please contact us for more details
• There are 4 key layers for the Array
  • Layer 1: The bottom, which is translucent with a light backdrop
  • Layer 2: The walls of the individual maze. (Height: 1/16 in)
  • Layer 3: Infrastructure around the maze to allow for robust strength to each array
  • Layer 4: A clear non reflective acrylic lid.

Documentation

Introduction

The Drosophila Maze Array is designed to study locomotor behavior in Drosophila. Locomotor behavior is a form of behavioral handedness or the preferential performance of behavior on one side of the body or with a particular chiral twist (Buchanan, 2015). This locomotor handedness is not related to a genetic dominance or morphological asymmetry. Instead, it is related to the asymmetric involved in the collection and processing of sensory information by the subject. In the Drosophila Maze Array, light and different pattern configurations are used to study how specific sensory exposures affect Drosophila’s locomotive behavior. The Y-maze Array configuration is an efficient test to evaluate the chemosensory responses in Drosophila (Simonnet, 2014). The T-maze Array configuration can be utilized to test memory (Malik, 2014) and phototaxic reflex in adult flies (Swinderen, 2011). By studying Drosophila locomotor behavior using the different maze array configurations, one can start to understand and analyze the variability in physiological, morphological and behaviors exhibited by Drosophila that has grown up in identical environments (Buchanan, 2015).

Apparatus and Equipment

The Drosophila Maze Array consists of four layers, each representing a specific purpose. The first layer is the bottom of the maze, it is made of translucent material and contains a light backdrop. The second layer is the walls of the individual maze that can be configured as requested. The height of the walls is 1/16^th inch no matter the configuration. The third layer of the maze is the infrastructure that surrounds the maze. This infrastructure provides the maze array with robust strength. The fourth and final layer consists of a non-reflective acrylic lid.

Training Protocol

Y and T- Shaped Configurations

Pre-Training

The subjects are starved the for about 16 to 18 hours and are maintained at 25⁰C.

Testing Procedure

Each maze is kept symmetrical for unbiased design. For automated activity tracking, ConductVision is placed at the top of the apparatus with all the lights properly lit. At the start of the experiment, flies are placed individually in the Y- shaped configuration with each maze evenly lit and symmetrical. The subject is allowed to move freely for the prescribed period, and the scoring is automatic. Turn bias score is referred as the time spent by the fly to pass the center of the maze and chose to go right (Buchanan et al. 2015).

T-Shaped Configuration

Pre-Training

The flies should be feed and stored at around 25⁰C and 70% humidity before being introduced to the maze. An air pump should be attached to the T-maze, to allow odors to be drawn across the flies, the air flow should be mild at ~2 L/min. Two different odors should be used, 4- methylcyclohexane (1:67) and 3-octanol (1:100) diluted in mineral oil. About 30µl of the diluted solution should be pipetted into a custom-made odor cup and placed in an odor block covered by a plastic tube with a perforated top to allow air to be drawn over the odor cup. Experiments should be performed under a dim red light that allows the researcher to see but prevents the flies from seeing so they can focus on olfaction instead of visual input.

Testing Procedure

Flies are introduced to the T-maze and are allowed to adapt to the airflow for 90 seconds. The first odor is introduced to the maze with a 60-V shock for 60 seconds. This is followed by 30 seconds of rest without the odor or the shock. The second odor is introduced for 60 seconds without a shock. The flies are then moved from the training tube to the central chamber of the T-ma

Evaluation of Chemosensory responses

The Y-maze Array configuration is an efficient test to evaluate the chemosensory responses in Drosophila (Simonnet, 2014).

Evaluation of Genetic variability for olfactory responses

The Y- type configuration was also employed to investigate the intrapopulation genetic variability for olfactory responses to odorous stimuli (Alcorta and Rubio 1998). The application of stimuli paired with the maze allows the researcher to understand locomotive behavioral characteristics of flies that were grown in identical environments. This information can, in turn, be applied to gathering a basic understanding of how genetically identical subjects can display a variability in their physiology, morphology, and behavior.

Evaluation of locomotor handedness

Buchanan et al. 2015 studied locomotor handedness in Drosophila melanogaster.

Modifications

The maze can be modified to include both “+” and “-” configurations.

Sample Data

Strengths & Limitations

Strengths

It can be utilized in a number of different configurations (T, Y, etc.) to adjust to the specific needs of any study. A Drosophila Maze Array can provide a platform to introduce Drosophila flies to a number of different stimuli (odor, light, shock waves) in order to study the locomotive behavior of the subjects.

Limitations

The limitations associated with a Drosophila Maze Array is that they are limited to odor and visual stimuli, and would need to be modified to allow for testing using other stimuli. Drosophila Maze Arrays must be used in controlled environments with minimized external factors.

Summary and Key Points

• The Drosophila Maze Array is designed to study locomotor behavior in Drosophila flies.
• The Drosophila Maze Array consists of four layers; a translucent backlit bottom, walls of the individual maze, infrastructure around the maze to allow for strength, and a clear reflective acrylic lid.
• The Drosophila Maze Array comes in four configurations’ Y, T, +, and -; and can be custom built upon request.

References

Buchanan, Sean M. Kain, Jamey S., and de Bivort, Benjamin L. (2015). Neuronal Control of Locomotor Handedness in Drosophila. PNAS, vol 112 (no. 21), p. 6700-6705.

Malik, Bilal R., and Hodge, James J.L. (2014). Drosophila Adult Olfactory Shock Learning. Journal of Visualized Experiments, vol. 90 (e50107), p. 1-5.

Martin, Fernando, Charro, Maria J., and Alcarta, Esther. (2001). Mutations Affecting the cAMP Transduction Pathway Modify Olfaction in Drosophila. J. Comp Physiol A, p. 359-370.

Simonnet, Megane M., Berthelot-Grosjean, Martine, Grosjean, Yael. (2014). Testing Drosophila Olfaction with a Y-maze Assay. Journal of Visualized Experiments, vol. 88 (e51241), p. 1-4.

Swinderen, Bruno van. (2011). Aversive Phototaxic Suppression Assay for Individual Adult Drosophila. Cold Spring Harbor Protocols, p. 1203-1205.

Alcorta E, Rubio J. (1989). Intrapopulational variation of olfactory responses in Drosophila melanogaster. Behav Genet ;19(2):285-99.