Temperature Gradient Assay: A Method to Test Temperature Preference in Drosophila Larvae
Published: April 30, 2023
Abstract
Source: Liu, J., et al. A Temperature Gradient Assay to Determine Thermal Preferences of Drosophila Larvae. J. Vis. Exp. (2018).
Drosophila fruit flies can distinguish small changes in temperature and therefore select environments with favorable thermal conditions. This video describes a behavioral assay that tests the temperature preference of Drosophila larvae on a linear thermal gradient.
Protocol
This protocol is an excerpt from Liu et al. A Temperature Gradient Assay to Determine Thermal Preferences of Drosophila Larvae, J. Vis. Exp. (2018). 1. Temperature Gradient Setup Prepare single-directional gradient To create a humid ambient environment during the assays, place the two aluminum blocks connected to two water baths on wet paper towels, separated by 10 cm (Figure 1A).</…
Representative Results
Figure 1: Single and bidirectional gradient assay setups. (A) Single-directional gradient setup with two aluminum assay plates on two aluminum blocks. The temperatures of the aluminum blocks are controlled by circulating water from two water baths. (B) The arrangement of the three aluminum blocks, water baths and an aluminum plate (250 x 220 mm) for a bidirectional gradient. The left…
Materials
| Gradient assay apparatus | |||
| PolyScience 9106, Refrigerated/Heated 6L Circulating Bath | Thomas Scientific | 9106 | This model is discontinued. Updated replacement models include: 1186R00 and 1197U04 for 120 V, 60 Hz, or 1184L08 and 1197U04 for 240 V, 50 Hz. |
| Aluminum assay plate (for single directional gradient) | Outer size: 14 x 10.1 x 0.9 cm, inner size: 12.9 x 8.7 x 0.8 cm, black anodized. | ||
| Aluminum plate (for bidirectional gradient) | 25 x 22 x 0.2 cm, black anodized. | ||
| Aluminum block | Outer size: 25.5 x 5 x 1.4 cm, parameters of inner channels are shown in Figure 1D. | ||
| Connector for aluminum blocks and tubing | McMaster-Carr | 91355K82 | |
| Tygon Sanitary Silicone Tubing | Tygon | 57296 | 1/4" ID x 3/8" OD x 1/16" wall |
| Name | Company | Catalog Number | Comments |
| Items and reagents for assay | |||
| Pestle | USA Scientific | 17361 | Pestle for 1.5 mL microcentrifuge tubes |
| Thermometer | Fluke | 51II | |
| Thermocouple | Fluke | K type | |
| Universal microplate lid | Corning | 6980A77 | |
| 35 mm dish | Corning | 9380D40 | |
| Labeling tape (for bidirectional gradient) | Fisher Scientific | 15-951 | Fisherbrand labeling tape 2 in x 14 yds |
| Agarose | Invitrogen | 16500500 | Prepare 1% solution |
| Sucrose | Sigma | S0389-5KG | Prepare 18% solution right before starting assay |
| Paint brush | Fisher Scientific | 11860 | |
| 50 mL centrifuge tubes | Denville | C1062-P | |
| Scoopula | Fisher Scientific | 14-357Q | |
| 500 mL round wide-mouth bottle | Pyrex | 1395-500 | |
| Cell strainer (300 mm pore) | PluriSelect | 43-50300 | Optional item for larvae washing |
| Cardboard box (vial tray) | Genesee Scientific | FS32-124 |
Citar este artigo
Temperature Gradient Assay: A Method to Test Temperature Preference in Drosophila Larvae. J. Vis. Exp. (Pending Publication), e20147, doi: (2023).