Trio preserves motor synapses and prolongs motor ability during aging

Area of Science:

• Neuroscience
• Aging Research
• Molecular Biology

Background:

• Motor ability decline is a key aspect of aging, linked to motor synaptic terminal degeneration.
• Drosophila motor synapses show age-dependent structural fragmentation and reduced motor ability.

Purpose of the Study:

• To investigate the role of Trio, a guanine nucleotide exchange factor (GEF), in age-dependent motor synapse decline.
• To determine if increasing Trio levels can mitigate age-related synaptic and motor function deterioration.

Main Methods:

• Quantified age-dependent changes in Drosophila motor synapse structure and function.
• Manipulated Trio protein levels in adult Drosophila using transgenics.
• Assessed the impact of Trio on synaptic integrity, neurotransmitter release capacity, and motor behavior.
• Investigated the requirement of Trio's Rac GEF function and tested human Trio's efficacy.

Main Results:

• Motor synapse levels of Trio decrease with age in Drosophila.
• Elevated Trio expression prevented age-dependent synaptic fragmentation and motor ability decline.
• Increased Trio maintained high-intensity neurotransmitter release and ameliorated synapse degeneration from other causes.
• Trio's Rac GEF function is essential for its protective effects, which are conserved in human Trio.

Conclusions:

• Trio plays a critical role in maintaining motor synapse structure and function during aging.
• The structural breakdown of motor synapses precedes motor behavioral decline.
• Interventions targeting Trio can potentially postpone age-related motor function loss.