A single-component optogenetic toolkit for programmable control of microtubule

Area of Science:

• Cell Biology
• Biophysics
• Molecular and Structural Biology

Background:

• Microtubules (MTs) are crucial cytoskeletal components regulating intracellular transport, organelle positioning, and signaling.
• MT dynamics are modulated by microtubule-associated proteins (MAPs), post-translational modifications (PTMs), and molecular motors.

Purpose of the Study:

• To develop a genetically encoded optogenetic toolkit for precise spatiotemporal control of MT organization and dynamics in living systems.
• To investigate the functional link between MT integrity, PTMs, and cellular processes like trafficking and signaling.

Main Methods:

• Engineered single-component probes (OptoMT, OptoTIP) using blue light-responsive oligomerization domains for MT labeling and plus-end tracking.
• Developed light-activatable modules (OptoMotor, OptoSAW) for controlling tubulin PTMs, cargo transport, and MT disassembly.
• Utilized the toolkit to perturb MTs and observe effects on lysosomal trafficking and ER-associated signaling.

Main Results:

• Demonstrated reversible control over MT labeling and plus-end tracking with tunable kinetics (seconds to minutes).
• Showcased localized induction of tubulin acetylation and detyrosination, linking PTMs to MT stability.
• Revealed the impact of local MT integrity on lysosomal trafficking and ER signaling dynamics.

Conclusions:

• The developed optogenetic toolkit provides unprecedented spatiotemporal control over MT organization and dynamics.
• This toolkit enables direct interrogation of how MT architecture coordinates intracellular organization, transport, and signaling.
• Offers new avenues for studying cytoskeletal function and its role in cellular processes.