Any process that initiates the activity of an inactive GTPase through the replacement of GDP by GTP.

A series of molecular signals within the cell that are mediated by a member of the Rho family of proteins switching to a GTP-bound active state.

The aggregation, arrangement and bonding together of a set of components to form a synapse. This process ends when the synapse is mature (functional).

The aggregation, arrangement and bonding together of a set of components to form a synapse. This process ends when the synapse is mature (functional).

The directed movement of organelles or molecules along microtubules in neuron projections.

A process that is carried out at the cellular level which results in the assembly, arrangement of constituent parts, or disassembly of a prolongation or process extending from a cell, e.g. a flagellum or axon.

A process that is carried out at the cellular level which results in the assembly, arrangement of constituent parts, or disassembly of a prolongation or process extending from a cell, e.g. a flagellum or axon.

Any process in which a protein is transported to, and/or maintained in, a specific location at the level of a cell. Localization at the cellular level encompasses movement within the cell, from within the cell to the cell surface, or from one location to another at the surface of a cell.

Self-propelled movement of a cell or organism from one location to another.

The process whose specific outcome is the progression of the R7 photoreceptor over time, from its formation to the mature structure. The R7 photoreceptor is the last photoreceptor to develop in the ommatidium.

The assembly and arrangement of cytomatrix proteins to form complexes in the cell cortex beneath the active zone, i.e. just beneath the presynaptic plasma membrane.

A process which maintains the organization and the arrangement of proteins at the active zone to ensure the fusion and docking of vesicles and the release of neurotransmitters.

The long distance growth of a single cell process, that is involved in the migration of an axon growth cone, where the migration is directed to a specific target site by a combination of attractive and repulsive cues.

Any process that modulates the frequency, rate or extent of small GTPase mediated signal transduction.

Any process that initiates the activity of an inactive GTPase through the replacement of GDP by GTP.

Any process in which a synaptic vesicle or vesicles are transported to, and/or maintained in, a specific location.

A process that results in the assembly, arrangement of constituent parts, or disassembly of a presynaptic active zone.

The part of the cytoplasm that does not contain organelles but which does contain other particulate matter, such as protein complexes.

The junction between the axon of a motor neuron and a muscle fiber. In response to the arrival of action potentials, the presynaptic button releases molecules of neurotransmitters into the synaptic cleft. These diffuse across the cleft and transmit the signal to the postsynaptic membrane of the muscle fiber, leading to a change in post-synaptic potential.

The junction between the axon of a motor neuron and a muscle fiber. In response to the arrival of action potentials, the presynaptic button releases molecules of neurotransmitters into the synaptic cleft. These diffuse across the cleft and transmit the signal to the postsynaptic membrane of the muscle fiber, leading to a change in post-synaptic potential.

A specialized area of membrane of the axon terminal that faces the plasma membrane of the neuron or muscle fiber with which the axon terminal establishes a synaptic junction; many synaptic junctions exhibit structural presynaptic characteristics, such as conical, electron-dense internal protrusions, that distinguish it from the remainder of the axon plasma membrane.

The junction between a nerve fiber of one neuron and another neuron, muscle fiber or glial cell. As the nerve fiber approaches the synapse it enlarges into a specialized structure, the presynaptic nerve ending, which contains mitochondria and synaptic vesicles. At the tip of the nerve ending is the presynaptic membrane; facing it, and separated from it by a minute cleft (the synaptic cleft) is a specialized area of membrane on the receiving cell, known as the postsynaptic membrane. In response to the arrival of nerve impulses, the presynaptic nerve ending secretes molecules of neurotransmitters into the synaptic cleft. These diffuse across the cleft and transmit the signal to the postsynaptic membrane.

The junction between a nerve fiber of one neuron and another neuron, muscle fiber or glial cell. As the nerve fiber approaches the synapse it enlarges into a specialized structure, the presynaptic nerve ending, which contains mitochondria and synaptic vesicles. At the tip of the nerve ending is the presynaptic membrane; facing it, and separated from it by a minute cleft (the synaptic cleft) is a specialized area of membrane on the receiving cell, known as the postsynaptic membrane. In response to the arrival of nerve impulses, the presynaptic nerve ending secretes molecules of neurotransmitters into the synaptic cleft. These diffuse across the cleft and transmit the signal to the postsynaptic membrane.

A specialized region of the plasma membrane and cell cortex of a presynaptic neuron; encompasses a region of the plasma membrane where synaptic vesicles dock and fuse, and a specialized cortical cytoskeletal matrix.

A specialized region below the presynaptic membrane, characterized by electron-dense material, a specialized cytoskeletal matrix and accumulated (associated) synaptic vesicles.