A possible postsynaptic role for SNAP-25 in hippocampal synapses

TY - JOUR

T1 - A possible postsynaptic role for SNAP-25 in hippocampal synapses

AU - Hussain, S.

AU - Ringsevjen, H.

AU - Schupps, M.

AU - Hvalby, Ø.

AU - Sørensen, J. B.

AU - Jensen, V.

AU - Davanger, S.

N1 - Correction to: A possible postsynaptic role for SNAP-25 in hippocampal synapses DOI: 10.1007/s00429-018-01823-3

PY - 2019/3/4

Y1 - 2019/3/4

N2 - The SNARE protein SNAP-25 is well documented as regulator of presynaptic vesicle exocytosis. Increasing evidence suggests roles for SNARE proteins in postsynaptic trafficking of glutamate receptors as a basic mechanism in synaptic plasticity. Despite these indications, detailed quantitative subsynaptic localization studies of SNAP-25 have never been performed. Here, we provide novel electron microscopic data of SNAP-25 localization in postsynaptic spines. In addition to its expected presynaptic localization, we show that the protein is also present in the postsynaptic density (PSD), the postsynaptic lateral membrane and on small vesicles in the postsynaptic cytoplasm. We further investigated possible changes in synaptic SNAP-25 protein expression after hippocampal long-term potentiation (LTP). Quantitative analysis of immunogold-labeled electron microscopy sections did not show statistically significant changes of SNAP-25 gold particle densities 1 h after LTP induction, indicating that local trafficking of SNAP-25 does not play a role in the early phases of LTP. However, the strong expression of SNAP-25 in postsynaptic plasma membranes suggests a function of the protein in postsynaptic vesicle exocytosis and a possible role in hippocampal synaptic plasticity.

AB - The SNARE protein SNAP-25 is well documented as regulator of presynaptic vesicle exocytosis. Increasing evidence suggests roles for SNARE proteins in postsynaptic trafficking of glutamate receptors as a basic mechanism in synaptic plasticity. Despite these indications, detailed quantitative subsynaptic localization studies of SNAP-25 have never been performed. Here, we provide novel electron microscopic data of SNAP-25 localization in postsynaptic spines. In addition to its expected presynaptic localization, we show that the protein is also present in the postsynaptic density (PSD), the postsynaptic lateral membrane and on small vesicles in the postsynaptic cytoplasm. We further investigated possible changes in synaptic SNAP-25 protein expression after hippocampal long-term potentiation (LTP). Quantitative analysis of immunogold-labeled electron microscopy sections did not show statistically significant changes of SNAP-25 gold particle densities 1 h after LTP induction, indicating that local trafficking of SNAP-25 does not play a role in the early phases of LTP. However, the strong expression of SNAP-25 in postsynaptic plasma membranes suggests a function of the protein in postsynaptic vesicle exocytosis and a possible role in hippocampal synaptic plasticity.

KW - Electron microscopy

KW - Hippocampus

KW - LTP

KW - SNARE proteins

KW - Synaptic plasticity

UR - https://doi.org/10.1007/s00429-018-01823-3

U2 - 10.1007/s00429-018-1782-2

DO - 10.1007/s00429-018-1782-2

M3 - Journal article

C2 - 30377802

AN - SCOPUS:85055738116

SN - 1863-2653

VL - 224

SP - 521

EP - 532

JO - Brain Structure and Function

JF - Brain Structure and Function

IS - 2

ER -