STAMP: Spatio-Temporal Association Mapping of Proteins

Area of Science:

• Biochemistry
• Molecular Biology
• Cell Biology

Background:

• Protein-protein interactions (PPIs) are crucial for cellular functions.
• Identifying PPIs in specific cellular locations and times remains challenging.
• Cytidine 5'-triphosphate synthase (CTPS) forms filamentous structures called cytoophidia.

Purpose of the Study:

• To introduce Spatio-Temporal Association Mapping of Proteins (STAMP), a novel tool for identifying protein interactomes.
• To demonstrate the utility of STAMP for mapping in vivo PPIs with spatiotemporal resolution.
• To investigate PPIs of CTPS in various developmental stages and tissues of Drosophila.

Main Methods:

• STAMP utilizes proximity labeling with TurboID to biotinylate bait proteins.
• The method was applied to cytidine 5'-triphosphate synthase (CTPS) in Drosophila.
• Cell-specific GAL4 drivers were used to target labeling in individual cells.
• Wild-type and mutant CTPS were used as bait proteins to identify distinct proximate proteomes.

Main Results:

• STAMP successfully biotinylated the bait protein CTPS in situ.
• The application of STAMP identified distinct sets of proximate proteomes using wild-type and mutant CTPS.
• The study confirmed the feasibility of capturing in vivo PPIs at a defined spatiotemporal resolution.

Conclusions:

• STAMP is a powerful and feasible tool for identifying protein interactomes.
• The method enables the study of PPIs within specific cellular contexts and developmental times.
• STAMP provides a valuable approach for understanding the dynamic nature of protein interactions in vivo.