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Omelchenko, A. A.

Publications and source records attributed to Omelchenko, A. A..

3 recordsLinked to original sources

Responses to Temperatures of Different Drosophila Species

Temperature is a critical environmental variable that affects the distribution, survival, and reproduction of most animals. Although temperature receptors have been identified in different animals, how these receptors respond to temperatures is largely unknown. Here we use modified single-fly thermotactic assays to analyze movements and temperature preferences of nine Drosophila species. The ability/inclination to move varies among these species and at different temperatures. Importantly, different species prefer various ranges of temperatures. While wild-type D. melanogaster flies avoid the warm temperature in the warm avoidance assay and the cool temperature in the cool avoidance assay, D. bipectinata and D. yakuba avoid neither warm nor cool temperatures and D. biarmipes and D. mojavensis do not avoid the warm temperature in the warm avoidance assay. These results demonstrate that Drosophila species have different mobilities and temperature preferences, thereby benefiting the research on molecular mechanisms of temperature responsiveness. Summary statementThe ability to move and the preference for temperatures vary among fly species when flies are exposed to steep temperature gradients.

animal behavior and cognition↗

An open-source method for analysis of confocal calcium imaging with sparse cells

Research in the field of neuroscience has evolved to use complex imaging and computational tools to extract comprehensive information from data sets. Calcium imaging is a widely used technique that requires sophisticated software to obtain reproducible results, but many laboratories struggle to adopt computational methods when updating protocols to meet modern standards. Difficulties arise due to the lack of computational knowledge and paywalls for software. In addition, most calcium imaging analysis approaches ignore motion on the z-axis. Here, we described a workflow to use ImageJ to analyze 3D calcium imaging. We applied TrackMate, an open-source ImageJ plugin, to track neurons in the lateral (x/y) direction, detect regions of interest (ROIs), and extract fluorescence intensities. To track motion on the z-axis, we developed a new ImageJ plugin, TrackMate Analysis of Calcium Imaging (TACI). For neurons appearing on multiple z-positions, maximum fluorescence values were identified to represent neurons intensities of corresponding z-stacks. This workflow does not require coding ability, avoids human bias, and increases reproducibility. We validated this workflow using fly larval thermosensitive neurons that displayed movements in all directions during temperature fluctuation and a 3D calcium imaging dataset acquired from the fly brain.

neuroscience↗

Using TrackMate to Analyze Drosophila Larval and Adult Locomotion

Drosophila adult and larvae exhibit sophisticated behaviors that are widely used in development, synaptic transmission, sensory physiology, and learning and memory research. Many of these behaviors depend on locomotion, the ability of an animal to move. However, the statistical analysis of locomotion is not trivial. Here we use an open-source Fiji plugin TrackMate to track the locomotion of Drosophila adults and larvae. We build optimal experimental setups to rapidly process recordings by Fiji and analyze by TrackMate. We also provide tips for analyzing non-optimal recordings. TrackMate extracts the X and Y positions of an animal on each frame of an image sequence or a video. This information allows for generating moving trajectories, calculating moving distances, and determining preference indices in two-choice assays. Notably, this free-cost analysis method does not require programming skills. Summary statementThis study uses an open-source Fiji plugin TrackMate to computationally analyze Drosophila adult and larval behavioral assays, which does not require programming skills.

animal behavior and cognition↗