Figure 3.

Whole-cell Ca²⁺ current recordings in cells expressing the indicated Numb isoforms, cultured for 4–5 days after cell plating. A. Representative traces of Ca²⁺ currents (ICa) recorded from cells transfected with vector, or the indicated Numbs in response to the test potentials from −60 mV to 50 mV from a holding potential of −70 mV. B. Quantification of the mean Ca²⁺ current densities in cells expressing vector or the indicated Numb isoforms. Values are the mean ± SEM of the determinations made in 10–14 cells expressing each Numb isoform from 5 independent cultures in different days. *p<0.05, **p<0.01, ***p<0.001 compared to values of ICa density from cells transfected with vector and LPTB Numb, ANOVA followed by Holm-Sidak methods for multiple comparison. SPTB/SPRR-D: differentiated cells expressing SPTB/SPRR, SPTB/SPRR: undifferentiated cells expressing SPTB/SPRR Numb. C. Representative traces of Ca²⁺ currents recorded from cells transfected with vector in the presence or absence of NGF, or with SPTB/SPRR Numb in response to the test potential of 10 mV from a holding potential of −70 mV. D. The average changes in ICa density recorded in the cells expressing vector in the presence (n=6) or absence (n=6) of NGF and in the cells expressing SPTB/SPRR numb (n=7). Values are the mean ± SEM. *p<0.05, **p<0.01compared to the value of ICa density from the cells expressing vector, Student t-test.