1. Katherine Xiong 04-14-14

2. Figure 3A: GlutR1Ct and GlutR2Ct reduce branch stability 3 days after transfection GFP and GlutR1/2Ct transfected tectal neurons Time lapse imaging over 6 hours (every 2 hours)

3. Figure 3B-D: GlutR1Ct and GlutR2Ct reduce branch stability R1/R2 neurons = MORE DYNAMIC – Higher % branches retracted (Figure 3B) – Faster rate of loss of branches present at 0 hr (Figure 3C) – More branches with shorter lifespan (Figure 3D) R1/R2 neurons = LESS STABLE

4. Figure 4A: Synapses on GlutR1/2Ct are less mature Electron microscopy images  white arrow heads = synapses Looking at effects of AMPA c-tail expression presynaptically Stage 39 = tadpole developing limbs; Stage 47 = end of metamorphosis (frog) mature control; GFP = control transfected w/ GFP; Ctail = transfected w/ GlutR1Ct; stage 47

5. Figure 4B-D: GlutR1Ct prevents synapse maturation Developing synapse = increased synaptic vesicle/axon terminal profile Ac/At = area of synapse w/ clustered synaptic vesicle/total synapse area PSP = post synaptic profile R1 had less than half as much area occupied by synaptic vesicle clusters compared to S47 controls (Figure 4B) Most of synaptic vesicle clusters in R1 were of lower Ac/At ratios (Figure 4C) Synaptic contacts on R1 were on larger caliber dendrites (Figure 4D)

6. Figure 5: GluR1Ct block experience driven plasticity Total dendritic arbor length: – Decreased in GluR1Ct upon visual stimulation (Figure 5A) Number of branch tips: – Decreased in GluR1Ct with visual stimulation (Figure 5B) AMPAR transmission is required for experience dependent structural plasticity

7. Conclusions AMPAR-mediated gluatmatergic transmission is necessary for: – Dendritic arbor stabilization R1/R2 = shorter, fewer, and more dynamic – Synapse maturation R1/R2 = fewer vesicle clusters/presynaptic area – Experience dependent structural plasticity Visual activity retracts dendrites