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ABSTRACT In complex nervous systems, neurons must identify their correct partners to form synaptic connections. The prevailing model to ensure correct recognition posits that cell-surface proteins (CSPs) in individual neurons act as identification tags. Thus, knowing what cells express which CSPs would provide insights into neural development, synaptic connectivity, and nervous system evolution. Here, we investigated expression of Dpr and DIP genes, two CSP subfamilies belonging to the immunoglobulin superfamily, in Drosophila larval motor neurons (MNs), muscles, glia and sensory neurons (SNs) using a collection of GAL4 driver lines. We found that Dpr genes are more broadly expressed than DIP genes in MNs and SNs, and each examined neuron expresses a unique combination of Dpr and DIP genes. Interestingly, many Dpr and DIP genes are not robustly expressed, but are found instead in gradient and temporal expression patterns. In addition, the unique expression patterns of Dpr and DIP genes revealed three uncharacterized MNs. This study sets the stage for exploring the functions of Dpr and DIP genes in Drosophila MNs and SNs and provides genetic access to subsets of neurons.
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Cell Ablation Techniques for the Larval Drosophila Neuromuscular System
Tissue development requires local and long-distance communication between cells. Cell ablation experiments have provided critical insights into the functions of specific cell types and the tissue surrounding the dead cells. In theDrosophilaneuromuscular system, ablation of motor neurons and muscles has revealed the roles of the ablated cells in axon pathfinding and circuit wiring. For example, when muscles are denervated due to laser ablation of their motor neuron inputs, they receive ectopic innervation from neighboring motor neurons. Here, we describe two methods of specific cell ablation. The first is a genetic ablation approach that usesGAL4(ideally expressed in a small subset of cells) to drive expression of cell death genesreaperandhead involution defective. The second method relies on reactive oxygen species produced by light activation of theArabidopsis-derived Singlet Oxygen Generator, miniSOG2, expressed in a subset of cells. For the latter, the precision stems from both theGAL4and the restricting of the blue-light stimulation area.
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- Award ID(s):
- 2048080
- PAR ID:
- 10564913
- Publisher / Repository:
- Cold Spring Harbor Laboratory Press
- Date Published:
- Journal Name:
- Cold Spring Harbor Protocols
- ISSN:
- 1940-3402
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1101/pdb.prot108503
