Marquart A, Flockerzi V
Institut für Pharmakologie, Universität Heidelberg, Germany.
FEBS Lett. 1997 Apr 28;407(2):137-40. doi: 10.1016/s0014-5793(97)00316-5.
The beta subunits of voltage-gated calcium channels normalize current amplitude, kinetics and voltage dependence of these channels by interacting with the channel's pore forming subunit alpha1. By screening an epitope expression library of alpha1Ca fusion proteins, a beta2a binding site of 22 amino acids was identified within the I-II cytoplasmic linker but not on other cytoplasmic sequences of alpha1Ca. This binding site overlaps by 14 amino acids with the conserved 18 amino acid peptide assumed to be essential for alpha1-beta interaction. The common 14 amino acid motif of alpha1Ca is sufficient to bind beta2a, and in addition beta1a, beta3 and beta4.
电压门控性钙通道的β亚基通过与通道的孔形成亚基α1相互作用，使这些通道的电流幅度、动力学和电压依赖性正常化。通过筛选α1Ca融合蛋白的表位表达文库，在I-II胞质连接区内而非α1Ca的其他胞质序列中鉴定出一个22个氨基酸的β2a结合位点。该结合位点与假定对α1-β相互作用至关重要的保守18个氨基酸肽有14个氨基酸重叠。α1Ca的共同14个氨基酸基序足以结合β2a，此外还能结合β1a、β3和β4。
