Significantly reduced miniature end-plate current (mEPC) frequency in hom/hom mutants. A–C: the passive membrane properties membrane potential (Vm; A), capacitance (Cm; B), and membrane resistance (Rm; C) of fast-twitch muscle cells at 48 h postfertilization for the following different genotypes: wild type (WT), tardbp−/−, tardbpl−/−, het/hom, and hom/hom. hom/hom mutants displayed a significantly depolarized membrane potential compared with the other different genotypes (P < 0.01). D: recordings of mEPCs, which result from spontaneous release of quanta, were done. hom/hom mutants showed a significantly reduced frequency (**P < 0.01). *P < 0.05. E: representative mEPCs for 5 min for all different genotypes from a 10-min recording. F: mEPC amplitude. G: overlay of representative individual mEPC from all different genotypes. H and I: decay constant (τ; H) and rise time (I) were measured across all different genotypes. No other significant differences were found. Numbers in parentheses indicate sample sizes. Data are means ± SE.
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