中国医科大学学报2025，Vol.54Issue(4)：306-311,6.DOI:10.12007/j.issn.0258-4646.2025.04.004
钙调蛋白突变体D130V与心肌Cav1.2通道IQ基序的相互作用
Interaction between calmodulin mutant D130V and IQ motif of cardiac Cav1.2 channel
摘要
Abstract
Objective To investigate the binding interaction between the calmodulin(CaM)mutant D130V and the IQ motif of the car-diac Cav1.2 channel.Methods The binding of mutant CaM-D130V to the IQ motif was predicted by fold recognition modeling,homology modeling,and protein docking.The plasmid was transformed into Escherichia coli BL-21 sensory cells via heat shock at 42 ℃ to induce the expression of glutathione S-transferase(GST)fusion protein.The protein was extracted by ultrasonic fragmentation and purified using GS-4B beads.PreScission protease was applied to remove the GST.SDS-PAGE was performed to detect the purity of protein.A GST pull-down assay was conducted to detect the interaction between CaM-D130V and IQ motif.Results Protein docking results showed that both CaM-WT and CaM-D130V could bind to the IQ motif of the cardiac Cav1.2 channel,but the binding sites of the mutant CaM-D130V to the IQ motif were reduced,and its binding conformation was changed compared with the CaM-WT,with decreased binding energy(|S|reduced from 48.086 6 kcal/mol to 47.309 5 kcal/mol).The GST pull-down assay indicated that the binding of CaM-D130V to IQ motif significantly decreased(P＜0.01),and the affinity was significantly reduced at 2 mmol/L Ca2+concentration compared with CaM-WT.Conclusion The reduced binding ability of CaM-D130V to the IQ motif of the cardiac Cav1.2 channel may contribute to functional alterations in the channel.These findings provide a theoretical basis for understanding the pathogenesis of CaM mutant-associated cardio-vascular diseases as well as targeted therapies.关键词
钙调蛋白/突变体/心肌Cav1.2通道/结合能力/长QT综合征Key words
calmodulin/mutant/cardiac Cav1.2 channel/binding ability/long QT syndrome分类
医药卫生引用本文复制引用
唐路红,刘忆芳,潘雪婷,邢英美,郝丽英,苏敬阳..钙调蛋白突变体D130V与心肌Cav1.2通道IQ基序的相互作用[J].中国医科大学学报,2025,54(4):306-311,6.基金项目
辽宁省自然科学基金(2022-BS-139) （2022-BS-139）
中国博士后科学基金(2021M693914) （2021M693914）
