Axonal guidance by surface microstructuring for intracellular transport investigations

Area of Science:

• Cell Biology
• Biophysics
• Neuroscience

Background:

• Intracellular transport is vital for cell development, function, and survival.
• Active transport relies on molecular motors (kinesin, dynein) moving cargoes along microtubules.
• Understanding motor-microtubule interactions and diffusion is key for efficient transport, especially in motor neurons.

Purpose of the Study:

• To establish one-dimensional (1D) intracellular transport geometries for comparing experimental data with theoretical models.
• To investigate stochastic mechanisms in motor-microtubule interactions and diffusion processes.
• To provide a framework for validating and clarifying current theoretical transport models.

Main Methods:

• Guiding axonal outgrowth of pheochromocytoma (PC12) cells along predefined chemical surface structures (2 microm width) using microscale plasma-initiated patterning (microPIP).
• Utilizing one-dimensional (1D) geometries with aligned microtubules in straight axons.
• Quantifying intracellular transport of quantum dots (QDs) via a time-resolved mean-square displacement (MSD) analysis algorithm.

Main Results:

• Successfully created 1D intracellular transport geometries in PC12 cell axons.
• Quantified quantum dot (QD) transport dynamics in these controlled environments.
• Generated experimental data suitable for direct comparison with 1D theoretical transport models.

Conclusions:

• The established 1D geometries and quantification methods facilitate a direct link between theoretical predictions and experimental findings.
• This approach aids in dissecting and understanding the complex mechanisms of intracellular transport.
• The study provides a valuable tool for validating and refining theoretical models of molecular motor-driven transport.