Golgi-associated microtubules are fast cargo tracks and required for persistent cell migration

Area of Science:

• Cell Biology
• Microscopy
• Molecular Motors

Background:

• Microtubules originating from the Golgi apparatus (Golgi MTs) are suggested to be crucial for sustained cell migration.
• The precise mechanisms governing Golgi MT-dependent vesicular transport and their role in cell motility are not fully understood.
• Direct observation of post-Golgi cargo trafficking along these specific microtubule structures has been limited.

Purpose of the Study:

• To investigate the role of Golgi MTs in post-Golgi vesicular trafficking and cell migration.
• To elucidate the structural and dynamic properties of Golgi MTs compared to non-Golgi MTs.
• To determine the functional significance of Golgi MTs in persistent cell movement.

Main Methods:

• Super-resolution stochastic optical reconstruction microscopy (STORM) for high-resolution imaging of microtubules and cargo.
• Live-cell imaging to observe dynamic trafficking events.
• Optogenetic manipulation to control cell direction and assess migration dynamics.

Main Results:

• Post-Golgi cargos exhibit higher enrichment and significantly faster movement on Golgi MTs compared to non-Golgi MTs.
• Golgi MTs display distinct morphology: increased polarization towards the cell leading edge, fewer intersections, greater stability, and fewer repair sites.
• Cargo pausing occurs at microtubule intersections and defects; Golgi MTs are vital for persistent migration but not for changing direction.

Conclusions:

• Golgi MTs function as specialized 'fast tracks' facilitating efficient anterograde transport of post-Golgi cargos.
• The unique structural and dynamic properties of Golgi MTs underpin their role in directed cell migration.
• This study provides direct evidence for the essential contribution of Golgi MTs to persistent cell motility.