Reduced SNAP-25 alters short-term plasticity at developing glutamatergic synapses

Area of Science:

• Neuroscience
• Molecular Biology
• Cell Biology

Background:

• SNAP-25 ( सहायता न्यूरोनल गतिविधि प्रोटीन 25) is crucial for synaptic vesicle fusion and implicated in psychiatric disorders.
• Reduced SNAP-25 expression is observed in schizophrenia and ADHD, but its functional impact remains unclear.

Purpose of the Study:

• To investigate how reduced SNAP-25 levels affect synaptic transmission properties.
• To elucidate the mechanisms underlying neuronal circuit alterations in psychiatric diseases associated with decreased SNAP-25.

Main Methods:

• Utilized neuronal cultures at 13-14 days in vitro (DIV) with halved SNAP-25 levels.
• Assessed evoked glutamatergic neurotransmission, spontaneous quantal events, and readily releasable vesicle pools.
• Analyzed short-term plasticity using paired-pulse stimulation.

Main Results:

• Halved SNAP-25 levels enhanced evoked glutamatergic neurotransmission without affecting spontaneous events or vesicle pools.
• Synapses with reduced SNAP-25 exhibited paired-pulse depression, unlike paired-pulse facilitation in wild-type controls.
• This plasticity phenotype was transient, disappearing with synapse maturation.

Conclusions:

• Reduced SNAP-25 enhances synaptic transmission and alters short-term plasticity in developing neurons.
• These findings offer mechanistic insights into cognitive impairments in intellectual disabilities and psychiatric disorders linked to SNAP-25 reduction.