GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:11124895

From GONUTS
Jump to: navigation, search
Citation

Allen, MJ, Shan, X and Murphey, RK (2000) A role for Drosophila Drac1 in neurite outgrowth and synaptogenesis in the giant fiber system. Mol. Cell. Neurosci. 16:754-65

Abstract

Recent studies have shown the small GTPases, Rac1, Rho, and CDC42, to have a role in axon guidance. To assess their participation in synapse assembly and function we have expressed various forms of Drac1 in the giant fiber system of Drosophila. Overexpression of wild-type Drac1 in the giant fiber (GF) lead to a disruption in axonal morphology; axons often terminate prematurely in a large swelling in the target area but lack the normal lateral bend where the synapse with the jump motor neuron would normally be found. Electrophysiological assays revealed longer latencies and lowering following frequencies indicating defects in the synapse between the GF and the tergotrochanteral motor neuron (TTMn). Thickened abnormal GF dendrites were also observed in the brain. Overexpression of the dominant-negative form of Drac1, (N17), resulted in axons that produced extra branches in the second thoracic neuromere (T2); however, the synaptic connection to the TTMn was present and functioned normally. Conversely, expression of the constitutively active form, Drac1(V12), resulted in a complete lack of neurite outgrowth and this was also seen with overexpression of Dcdc42(V12). In the absence of a GF, these flies showed no response in the jump (TTM) or flight (DLM) muscles upon brain stimulation. Taken together these results show that the balance of actin polymerization and depolymerization determines local process outgrowth and thereby synapse structure and function.

Links

PubMed Online version:10.1006/mcne.2000.0903

Keywords

Action Potentials/genetics; Animals; Cell Size/genetics; Central Nervous System/cytology; Central Nervous System/growth & development; Central Nervous System/metabolism; Drosophila/cytology; Drosophila/growth & development; Drosophila/metabolism; Drosophila Proteins; GTP-Binding Proteins/genetics; GTP-Binding Proteins/metabolism; Ganglia, Invertebrate/cytology; Ganglia, Invertebrate/growth & development; Ganglia, Invertebrate/metabolism; Gene Expression Regulation, Developmental/physiology; Nerve Fibers/metabolism; Nerve Fibers/ultrastructure; Neural Pathways/cytology; Neural Pathways/growth & development; Neural Pathways/metabolism; Neurites/metabolism; Neurites/ultrastructure; Synapses/metabolism; Synapses/ultrastructure; rac GTP-Binding Proteins/genetics; rac GTP-Binding Proteins/metabolism

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

DROME:RAC1

involved_in

GO:0031175: neuron projection development

ECO:0000315: mutant phenotype evidence used in manual assertion

P

Seeded From UniProt

complete

DROME:RAC1

involved_in

GO:0051963: regulation of synapse assembly

ECO:0000315: mutant phenotype evidence used in manual assertion

P

Seeded From UniProt

complete

DROME:CDC42

involved_in

GO:0031175: neuron projection development

ECO:0000315: mutant phenotype evidence used in manual assertion

P

Seeded From UniProt

complete


See also

References

See Help:References for how to manage references in GONUTS.