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Abstract The auxin-inducible degradation system has been widely adopted in the Caenorhabditis elegans research community for its ability to empirically control the spatiotemporal expression of target proteins. This system can efficiently degrade auxin-inducible degron (AID)-tagged proteins via the expression of a ligand-activatable AtTIR1 protein derived from A. thaliana that adapts target proteins to the endogenous C. elegans proteasome. While broad expression of AtTIR1 using strong, ubiquitous promoters can lead to rapid degradation of AID-tagged proteins, cell type-specific expression of AtTIR1 using spatially restricted promoters often results in less efficient target protein degradation. To circumvent this limitation, we have developed an FLP/FRT3-based system that functions to reanimate a dormant, high-powered promoter that can drive sufficient AtTIR1 expression in a cell type-specific manner. We benchmark the utility of this system by generating a number of tissue-specific FLP-ON::TIR1 drivers to reveal genetically separable cell type-specific phenotypes for several target proteins. We also demonstrate that the FLP-ON::TIR1 system is compatible with enhanced degron epitopes. Finally, we provide an expandable toolkit utilizing the basic FLP-ON::TIR1 system that can be adapted to drive optimized AtTIR1 expression in any tissue or cell type of interest.
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Labeling of Cell Surface Proteins at the Drosophila Larval Neuromuscular Junction Using Binding Partner Peptides
Determining the precise localization of interacting proteins provides fundamental insight into their putative function. Classically, immunolabeling of endogenous proteins or generating tagged versions of proteins has been used to localize interacting proteins. However, in many cases, the interacting partner of a protein of interest is unknown. For cell surface proteins, it is possible to determine the localization of interacting proteins if one of the binding partners is known. This approach is based on generating purified, recombinant, tagged extracellular domains (ECDs) of a protein of interest, and incubating tissue to allow the recombinant protein to bind to its interacting partner(s). In this protocol, we detail the cloning of secreted, tagged ECDs from cell surface proteins, transfection of cloned plasmids into S2 cells, collection of secreted domains, concentration of the cell culture medium to enrich for the ECDs, and labeling of tissue with these ECDs.
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- Award ID(s):
- 2048080
- PAR ID:
- 10564911
- 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.prot108501
