Abstract
Ca2+ channel β subunits determine the transport and physiological properties of high voltage-activated Ca2+ channel complexes. Our analysis of the distribution of the Cavβ subunit family members in hippocampal neurons correlates their synaptic distribution with their involvement in transmitter release. We find that exogenously expressed Cavβ4b and Cavβ 2a subunits distribute in clusters and localize to synapses, whereas Cavβ1b and Cavβ3 are homogenously distributed. According to their localization, Ca vβ2a and Cavβ4b subunits modulate the synaptic plasticity of autaptic hippocampal neurons (i.e., Ca vβ2a induces depression, whereas Ca vβ4b induces paired-pulse facilitation [PPF] followed by synaptic depression during longer stimuli trains). The induction of PPF by Cavβ4b correlates with a reduction in the release probability and cooperativity of the transmitter release. These results suggest that Cavβ subunits determine the gating properties of the presynaptic Ca2+ channels within the presynaptic terminal in a subunit-specific manner and may be involved in organization of the Ca 2+ channel relative to the release machinery.
Original language | English (US) |
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Pages (from-to) | 489-502 |
Number of pages | 14 |
Journal | Journal of Cell Biology |
Volume | 178 |
Issue number | 3 |
DOIs | |
State | Published - Jul 30 2007 |
Externally published | Yes |
ASJC Scopus subject areas
- Cell Biology