Rapamycin-based inducible translocation systems for studying phagocytosis

Area of Science:

• Immunology
• Cell Biology
• Molecular Biology

Background:

• Phagocytosis is a critical cellular process for engulfing particles, involving dynamic, sequential events.
• Investigating these dynamic events in live cells requires noninvasive methods for protein recruitment.
• Understanding phagocytosis regulation necessitates tools to dissect protein functions at specific cellular locations.

Purpose of the Study:

• To describe a genetically encoded rapamycin-induced heterodimerization system for targeted protein recruitment in macrophages.
• To enable dynamic and temporally controlled studies of phagocytosis and other organelle-related processes.
• To provide a versatile method for dissecting regulatory mechanisms in live-cell imaging.

Main Methods:

• Utilized a rapamycin-inducible system based on FKBP and FRB protein association.
• Engineered a synthetic system to recruit proteins of interest fused to FRB to specific cellular locations via FKBP-fusion targeting domains.
• Employed fluorescent microscopy to monitor protein recruitment in RAW264.7 murine macrophages.

Main Results:

• Successfully demonstrated the rapamycin-induced heterodimerization system for protein recruitment.
• Showcased the system's ability to target proteins to phagosomes and plasma membranes.
• Validated the monitoring of FRB-module recruitment using fluorescent microscopy.

Conclusions:

• The developed rapamycin-induced system offers a powerful, noninvasive tool for studying dynamic cellular processes like phagocytosis.
• This method facilitates the dissection of protein functions and regulatory mechanisms in live cells.
• The system's adaptability allows its application to various organelles beyond phagocytosis.