Description

Snap-8 (Acetyl Octapeptide-3) – Technical Biochemical Mechanism Profile

(Argireline-Derived Octapeptide; SNARE Complex Modulation Peptide – Research Use Only)

SNAP-8 is a synthetic octapeptide analog derived from the N-terminal domain of SNAP-25, a core component of the SNARE (Soluble NSF Attachment Protein Receptor) complex.
In in-vitro biochemical assays, SNAP-8 acts as a competitive substrate analog that interferes with vesicle docking and fusion by altering SNARE protein interactions that regulate Ca²⁺-dependent neurotransmitter and neuromodulator release.

✅ 1. Core Molecular Targets

SNAP-8 interacts with components of the SNARE fusion machinery, primarily:

SNAP-8 mimics the N-terminal SNAP-25 domain, competing for binding and modifying complex formation kinetics.

✅ 2. Biochemical Pathway – SNARE Complex Modulation

Normal Exocytosis Sequence:

1. V-SNARE (VAMP) + T-SNAREs (SNAP-25 + Syntaxin)

2. “Zippering” of SNARE helix bundles

3. Membrane fusion

4. Vesicle release triggered by Ca²⁺-bound synaptotagmin

With SNAP-8 present (in vitro models):

• Competes with SNAP-25 for SNARE binding sites

• Incomplete trans-SNARE complex assembly

• Altered helical “zippering”

• Modified Ca²⁺-triggered vesicle fusion efficiency

• ↓ synaptic vesicle release capacity

✅ 3. Cell Signaling & Second Messengers

Although SNAP-8 does not directly activate classical receptors, downstream effects of reduced vesicle fusion can influence:

• Ca²⁺ influx demands from voltage-gated Ca²⁺ channels (CaV2.1 / CaV2.2)

• PKC and Calmodulin pathways linked to synaptic release

• Feedback on cAMP–PKA signaling through reduced GPCR neurotransmitter output

✅ 4. Key Enzymes / Proteins Potentially Affected

Modification of SNARE complex assembly changes vesicle fusion turnover and NSF cycling dynamics.

✅ 5. Gene Targets Often Monitored in Assays

While SNAP-8 does not directly regulate gene transcription, in vitro gene-expression studies typically monitor:

• SNAP25, STX1A, VAMP2 (SNARE machinery)

• SYT1 (synaptotagmin)

• CACNA1A / CACNA1B (Ca²⁺ channels)

• RAB3A (vesicle trafficking)

• SLC17A7, SLC32A1 (vesicular transporters)

These genes act as biomarkers for synaptic vesicle docking and regulated exocytosis.

✅ Mechanistic Summary

• Synthetic octapeptide derived from SNAP-25 N-terminal domain

• Functions as competitive substrate analog for SNARE complex

• Reduces SNARE helix formation → vesicle fusion modulation

• Alters Ca²⁺-triggered exocytosis of synaptic vesicles in vitro

• Does not operate through GPCRs or membrane receptors

• Affects key proteins: SNAP-25, Syntaxin-1A, VAMP2, Synaptotagmin, NSF

✅ Research-Only Classification

SNAP-8 is supplied solely as a laboratory research chemical for in-vitro or biochemical experimentation.
Not approved for human or animal use, ingestion, injection, topical application, or therapeutic purposes.