Table 2.
Functional changes in NMJs and central synapses upon knockout of active zone proteins.
| Synapse | Gene Knockout | Excitatory/Inhibitory | Evoked EPSC/IPSC/EPP Amplitude | Miniature EPSC/IPSC/EPP Amplitude | Miniature EPSC/IPSC/EPP Frequency | Release Probability | RRP Size | Reference |
|---|---|---|---|---|---|---|---|---|
| Schaffer collateral to hippocampal CA1 pyramidal cell synapses (3- to 7-week) and cultured hippocampal synapses |
Rim1a and Rim1b |
Excitatory | N.P. | No change | Decrease | Decrease | N.P. | [37,38] |
| Hippocampal CA1 synapses (3- to 7-week) and cultured hippocampal synapses |
Rim1a and Rim1b |
Inhibitory | Decrease | No change | Decrease | Decrease | Decrease | [37,38] |
| Calyx of Held synapses in brainstem slices (Postnatal day 9–11) |
Rim1 and Rim2 |
Excitatory | 1/5-fold decrease |
No change | N.P. | ~25% decrease |
75% decrease |
[39] |
| Cultured hippocampal synapses |
Rim1 and Rim2 |
Excitatory | 1/10-fold decrease | No change | 1/10-fold decrease |
N.P. | 1/3- to 1/4-fold decrease |
[40,41] |
| Cultured hippocampal synapses |
Rim1 and Rim2 |
Inhibitory | 1/10-fold decrease |
No change | 1/3-fold decrease |
Decrease | 1/3- to 1/4-fold decrease |
[40,41] |
| Diaphragm NMJs (Embryonic day 18.5) |
Rim1a and Rim2a |
Excitatory | 1/10-fold decrease |
No change | No change (decrease in 40 mM KCl) | Decrease | N.P. | [33] |
| Cultured hippocampal synapses | Munc13-1 | Excitatory | Markedly decrease | No change | Decrease | No change | Markedly decrease |
[42] |
| Cultured hippocampal synapses | Munc13-1 | Inhibitory | No change | N.P. | N.P. | N.P. | No change | [42,43] |
| Cultured hippocampal synapses | Munc13-2 | Excitatory | No change | No change | No change | N.P. | No change | [43] |
| Cultured hippocampal synapses | Munc13-2 | Inhibitory | No change | No change | No change | N.P. | N.P. | [43] |
| Cultured hippocampal synapses |
Munc13-1 and Munc13-2 |
Excitatory | Completely abolish | Completely abolish | Completely abolish | N.P. | Completely abolish | [43] |
| Cultured hippocampal synapses |
Munc13-1 and Munc13-2 |
Inhibitory | Completely abolish | Completely abolish | Completely abolish | N.P. | N.P. | [43] |
| Diaphragm NMJs (Embryonic day 18.5) |
Munc13-1 and Munc13-2 |
Excitatory | 1/16-fold decrease |
No change | More than 2-fold increase | Decrease | Decrease | [32] |
| Schaffer collateral to hippocampal CA1 pyramidal cell synapses (4- to 6-week) and cultured hippocampal synapses | ELKS2a | Excitatory | N.P. | No change | No change | No change | No change | [44] |
| Hippocampal CA1 synapses (4- to 6-week) and cultured hippocampal synapses | ELKS2a | Inhibitory | Increase | No change | No change | Increase | Increase | [44] |
| Calyx of Held synapses in brainstem slices (Postnatal day 16–21) |
ELKS1 and ELKS2 |
Excitatory | No change | No change | Increase | Increase | Decrease | [45] |
| Cultured hippocampal synapses |
ELKS1a and ELKS2a |
Excitatory | 1/2-fold decrease |
No change | 1/2-fold decrease |
No change | Decrease | [46] |
| Cultured hippocampal synapses |
ELKS1a and ELKS2a |
Inhibitory | 1/2-fold decrease |
No change | 1/2-fold decrease |
Decrease | No change | [46,47] |
N.P.: not provided.