Dendritic filopodia

Dendritic filopodia are thin, long, flexible protrusions that extend from the dendrite of a developing neuron. They are involved in the formation of synapses, the junctions where neurons communicate with each other.

Function

Dendritic filopodia play a crucial role in the development of the nervous system. They explore the environment around the neuron, make contact with potential presynaptic partners, and initiate the formation of synapses.

Structure

Dendritic filopodia are composed of actin filaments. The actin in filopodia is organized into tight, parallel bundles that run along the length of the protrusion.

Formation

The formation of dendritic filopodia is regulated by a variety of proteins that control actin dynamics. These include proteins that promote actin polymerization, such as Ena/VASP proteins, and proteins that regulate actin filament branching, such as the Arp2/3 complex.

Role in Synapse Formation

When a dendritic filopodium makes contact with a potential presynaptic partner, it can initiate the formation of a synapse. This involves a series of changes in both the filopodium and the presynaptic neuron, including the accumulation of synaptic vesicles at the contact site and the recruitment of postsynaptic density proteins to the tip of the filopodium.

See Also

• Neuron
• Dendrite
• Synapse
• Actin
• Ena/VASP
• Arp2/3 complex
• Synaptic vesicle
• Postsynaptic density