Binds to membranes via its F-BAR domain and mediates membrane tubulation. Plays a role in cellular transport processes by recruiting dynamins to membranes. Plays a role in the reorganization of the actin cytoskeleton and in neuron morphogenesis via its interaction with cobl, and by recruiting cobl to the cell cortex. Plays a role in the regulation of neurite formation, neurite branching and the regulation of neurite length. Required for normal synaptic vesicle endocytosis; this process retrieves previously released neurotransmitters to accommodate multiple cycles of neurotransmission. Required for normal excitatory and inhibitory synaptic transmission (By similarity). Required for normal embryonic development, including normal development of laterality, normal body size and shape, as well as normal brain and heart development. Required for normal development of stereocilia and kinocilia in sensory hair cells of neuromasts in the posterior lateral line organ, and thus also for balance keeping and normal swimming behavior. Interacts with cobl. Detected in axons. In primary neuronal cultures, present at a high level in presynaptic nerve terminals and in the cell body. Detected at vesicular structures in neuron cell bodies and neurites (By similarity). Detected at the apical surface of cells at the basis of forming cilia, but not in the cilia themselves. Highly expressed throughout embryogenesis, from fertilization to hatching. Detected in embryonic neuronal tissues, including forebrain, hindbrain, spinal cord and retina. The F-BAR domain mediates membrane-binding and membrane tubulation.