Interactions between αCaMKII and calmodulin in living cells: conformational changes arising from CaM-dependent and -independent relationships.
Interactions between αCaMKII and calmodulin in living cells: conformational changes arising from CaM-dependent and -independent relationships.
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DOI：
10.1186/1756-6606-6-37
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发表时间：
2013-08-19
期刊：
影响因子：
3.6
通讯作者：
Kida S
中科院分区：
文献类型：
--
作者：
Kato K;Iwamoto T;Kida S
αCaMKII在长时程增强（LTP）、学习和记忆中起着核心和必要的作用。αCaMKII在Ca2+浓度升高时通过与Ca2+/CaM结合而激活。此外，Ca2+浓度的持续升高导致αCaMKII在T286位点的自磷酸化，即使在Ca2+/CaM解离后仍保持αCaMKII的活化。重要的是，αCaMKII的活性形式被认为表现出构象变化。为了阐明αCaMKII与CaM的相互作用与αCaMKII的构象变化之间的关系，我们制作了分子探针（YFP-αCaMKII与CFP-CaM和YFP-αCaMKII- cfp），并在活细胞中使用FRET分别对αCaMKII与CaM的相互作用和构象变化进行了时序成像。Ca2+浓度的升高同时诱导了YFP-αCaMKII与CFP-CaM的相互作用和YFP-αCaMKII- cfp的构象变化。与先前的预测一致，当CFP-CaM从YFP-αCaMKII中释放时，高水平的Ca2+信号维持了YFP-αCaMKII- cfp的构象变化。这些结果表明，α - camkii的构象变化由cam依赖性转变为cam非依赖性。此外，对αCaMKII突变体的分析表明，在与CaM的体内相互作用中，T286和T305/306位点的磷酸化分别发挥了积极和消极的作用，进一步表明CaM依赖性和CaM非依赖性构象改变形式具有相似但不同的结构。重要的是，cam依赖性和cam非依赖性αCaMKII之间的这些结构差异可能表现出αCaMKII的不同功能，例如与LTP和记忆所需的其他分子的相互作用。因此，我们的分子探针可用于识别与αCaMKII调节错误相关的认知障碍的治疗靶点。
αCaMKII plays central and essential roles in long-term potentiation (LTP), learning and memory. αCaMKII is activated via binding with Ca2+/CaM in response to elevated Ca2+ concentration. Furthermore, prolonged increase in Ca2+ concentration leads to the auto-phosphorylation of αCaMKII at T286, maintaining the activation of αCaMKII even after Ca2+/CaM dissociation. Importantly, the active form of αCaMKII is thought to exhibit conformational change. In order to elucidate the relationships between the interaction of αCaMKII with CaM and the conformational change of αCaMKII, we generated molecular probes (YFP-αCaMKII with CFP-CaM and YFP-αCaMKII-CFP) and performed time-lapse imaging of the interaction with CaM and the conformational change, respectively, in living cells using FRET. The interaction of YFP-αCaMKII with CFP-CaM and the conformational change of YFP-αCaMKII-CFP were induced simultaneously in response to increased concentrations of Ca2+. Consistent with previous predictions, high levels of Ca2+ signaling maintained the conformational change of YFP-αCaMKII-CFP at the time when CFP-CaM was released from YFP-αCaMKII. These observations indicated the transfer of αCaMKII conformational change from CaM-dependence to CaM-independence. Furthermore, analyses using αCaMKII mutants showed that phosphorylation at T286 and T305/306 played positive and negative roles, respectively, during in vivo interaction with CaM and further suggested that CaM-dependent and CaM-independent conformational changed forms displays similar but distinct structures. Importantly, these structual differences between CaM-dependent and -independent forms of αCaMKII may exhibit differential functions for αCaMKII, such as interactions with other molecules required for LTP and memory. Our molecular probes could thus be used to identify therapeutic targets for cognitive disorders that are associated with the misregulation of αCaMKII.
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影响因子：
64.8
作者：
Lee, Seok-Jin R.;Escobedo-Lozoya, Yasmin;Szatmari, Erzsebet M.;Yasuda, Ryohei
通讯作者：
Yasuda, Ryohei
DOI：
10.1073/pnas.92.24.11175
发表时间：
1995-11-21
影响因子：
11.1
作者：
LLEDO, PM;HJELMSTAD, GO;NICOLL, RA
通讯作者：
NICOLL, RA
影响因子：
64.5
作者：
BEACH, ME;HAWKINS, RD;MAYFORD, M
通讯作者：
MAYFORD, M
DOI：
10.1073/pnas.84.16.5962
发表时间：
1987-08-01
影响因子：
11.1
作者：
LIN, CR;KAPILOFF, MS;ROSENFELD, MG
通讯作者：
ROSENFELD, MG
影响因子：
64.5
作者：
MAYFORD, M;WANG, J;ODELL, TJ
通讯作者：
ODELL, TJ