Presynaptic filopodia form kinapses and promote convective membrane flow to sustain synchronous neurotransmitter release.

Dynamic presynaptic filopodia emerge during active synaptic transmission, deform synaptic boutons, and form transient contacts (“neuronal kinapses”) that favor increased synchronous neurotransmitter release.

• Why it matters: Structural remodeling of presynaptic boutons is poorly understood, yet it may be a key mechanism linking activity to changes in synaptic efficacy and timing precision.
• What they did: The study shows activity-dependent filopodia formation in intact circuits and human brain, and links filopodial growth to convective in-plane membrane flow toward the filopodium that accelerates release site clearance.
• The result: Membrane flow is associated with sustained release probability during repeated vesicle fusion and is linked to a shift toward synchronous over asynchronous neurotransmitter release.