DOI: 10.5061/dryad.ghx3ffc0b
title: Data for: A synapse-specific refractory period for plasticity at individual dendritic spines

description: How newly formed memories are preserved while brain plasticity is ongoing
 has been a source of debate. One idea is that synapses which experienced
 recent plasticity become resistant to further plasticity, a type of
 metaplasticity often referred to as saturation. Here, we probe the local
 dendritic mechanisms that limit plasticity at recently potentiated
 synapses. We show that recently potentiated individual synapses exhibit a
 synapse-specific refractory period for further potentiation. We further
 found that the refractory period is associated with reduced postsynaptic
 CaMKII signaling; however, stronger synaptic activation fully restored
 CaMKII signaling but only partially restored the ability for further
 plasticity. Importantly, the refractory period is released after one hour,
 a timing that coincides with the enrichment of several postsynaptic
 proteins to pre-plasticity levels. Notably, increasing the level of the
 postsynaptic scaffolding protein, PSD95, but not of PSD93, overcomes the
 refractory period. Our results support a model in which potentiation at a
 single synapse is sufficient to initiate a synapse-specific refractory
 period that persists until key postsynaptic proteins regain their
 steady-state synaptic levels.
description: # Dataset for: A synapse-specific refractory period for plasticity at
 individual dendritic spines. [Access Dataset on
 Dryad](https://doi.org/10.5061/dryad.ghx3ffc0b) # Overview Fluorescence
 data was collected using a custom-built 2-photon microscope. Green
 fluorescence from Green Fluorescent Protein (GFP) or Super Ecliptic
 Phluorin (SEP) were acquired in channel 1 and red fluoroescence from
 td-DsRed or DsRedExpress were acquired in channel 2. Analysis was
 performed using custom MATLAB software. Forster Resonance Energy
 Transfer-Fluorescence Lifetime Imaging Microscopy (FRET-FLIM) data was
 collected using a custom-built 2-photon microscope with time correlated
 single photon counting (TCSPC). Lifetime data is stored in channel 1 and
 the fluorescence intensity of a red cell fill is stored in channel 2. Data
 was analyzed using custom MATLAB software. ## Description of the data and
 file structure We have provided our raw data in the
 "FloresEtAl_2024_RawData.zip" file and our analysis files in the
 "FloresEtAl_2024_Analysis.zip" file. These two folders are
 sub-divided into files for each individual figure. ### Raw data: Folders
 for Figures 1, 2, 4, 5 & 6 contain date from 2-photon imaging
 experiments. These Figure folders are separated into Figure panels folders
 containing individual cells folders. Cell folders are named with the
 following convention: [initials, cell number]. Each cell folder contains
 all of the images for each cell in the experiment with the image name
 convention: [initials, cell number, dendrite identifier (a or b)].
 Z-stacks and maximum projection images are both included and stored in
 .tif format. A zoomed out image of the whole cell is included in .tif
 format with the name 'whole' added. Folders for Figures 3 &
 4 contain date from 2-photon FRET-FLIM experiments. These Figure folders
 are separated into Figure panels folders containing individual cells
 folders with the naming convention: [initials, cell number]. The cell
 folder contains the raw fluorescence data from channel 2 (red) and a
 sub-folder named "spc" which contains the raw single photon
 counting data per pixel. Both are stored in .tif format and use the naming
 convention [initials, cell number, dendrite identifier (a or b)]. The
 "spc" folders also include .mat files used to determine whether
 enough photons were collected. ### Analysis: Folders for Figures 1, 2, 4,
 5 & 6 contain analysis files for 2-photon imaging experiments. These
 Figure folders are separated into Figure panels folders containing .ann
 files and .xls files. The .ann files store integrated fluorescence data
 for green and red fluorescence (channel 1 and channel 2, respectively) and
 the positions of the analyzed ROIs. These have the naming convention
 [initials, cell number, dendrite identifier (a or b)]. The .xls files
 store the integrated background subtracted fluorescence for the analyzed
 spines with the naming convention [initials, cell number, dendrite
 identifier (a or b), channel (red or green)]. Folders for Figures 3 &
 4 contain analysis files for FRET-FLIM experiments. These Figure folders
 are separated into Figure panels folders containing .MAT files and .xls
 files. The .MAT files store data detailing the ROI position, the average
 lifetime (tau_m) and the red fluorescence intensity (int_int2). These .MAT
 files are named with the following convention:["A_", initials,
 cell number, dendrite identifier (a or b), "_ROI2"]. The .xls
 files store the raw lifetime and fluorescence intensities for each cell
 with the convention: [initials, cell number, dendrite identifier (a or
 b)]. All Figure folders contain summary .xlsx files where normalization
 and averaging of spine size or average lifetime across cells were
 performed. ## Usage Notes .tif images can be opened using most image
 analysis softwares (e.g. ImageJ) .MAT and .ann files can be opened using
 MATLAB .xls and .xlsx files can be opened using Microsoft Excel