Tau associates with actin in differentiating PC12 cells

Area of Science:

• Neuroscience
• Cell Biology

Background:

• Microtubule-associated protein tau is vital for axonal maintenance.
• Tau protein has demonstrated in vitro interactions with actin filaments.
• The in vivo interaction between tau and actin remains largely uncharacterized.

Purpose of the Study:

• To investigate the interaction between tau and actin in PC12 cells.
• To determine the role of nerve growth factor (NGF) in mediating tau-actin association.
• To identify the specific domains of tau protein responsible for actin binding.

Main Methods:

• Utilized PC12 cell line for studying tau-actin interactions.
• Applied NGF stimulation to induce cellular extensions and tau reorganization.
• Employed F-actin disruption assays to assess the necessity of actin assembly.
• Investigated truncated tau protein variants (N-terminal and C-terminal) fused to GFP.

Main Results:

• Tau-actin interaction was observed in PC12 cells specifically upon NGF stimulation.
• Tau localized to the ends of cellular extensions and associated with actin independently of microtubules.
• NGF-induced tau reorganization and actin association required F-actin assembly at extension tips.
• The C-terminal domain of tau (tau23) directly associated with actin, while the N-terminal domain did not.
• NGF enhanced the interaction between the tau C-terminus and actin.

Conclusions:

• The C-terminal region of tau is essential for its association with actin.
• The N-terminal region of tau may regulate the tau-actin interaction.
• NGF signaling is a key regulator of tau-actin association in cellular extensions.
• The tau-actin interaction is potentially involved in neurite outgrowth processes.