A genetically encoded ratiometric calcium sensor enables quantitative measurement of the local calcium microdomain in the endoplasmic reticulum  

作　　者：Chen Luo Huiyu Wang Qi Liu Wenting He Lin Yuan Pingyong Xu 

机构地区：[1]Key Laboratory of RNA Biology,Inst让ute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China [2]College of Life Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《Biophysics Reports》2019年第1期31-42,共12页生物物理学报（英文版）

基　　金：the National Key R&D Program of China (2016YFA0501500);the National Natural Science Foundation of China (31421002, 31401174 and 21778069);the Project of the Chinese Academy of Sciences (XDB08030203).

摘　　要：The local Ca^2+ release from the heterogeneously distributed endoplasmic reticulum (ER) calcium store has a critical role in calcium homeostasis and cellular function. However;single fluorescent proteinbased ER calcium probes experience challenges in quantifying the ER calcium store in differing live cells, and intensity-based measurements make it difficult to detect local calcium microdomains in the ER. Here, we developed a genetically encoded ratiometric ER calcium indicator [GCEPIA1-SNAPer] that can detect the real-time ER calcium store and local calcium microdomains in live cells. GCEPIA1-SNAPer was located in the lumen of the ER and showed a linear;reversible and rapid response to changes in the ER calcium store. The GCEPIA1-SNAPer probe effectively monitored the depletion of the ER calcium store by TG or starvation treatment, and through 让s use we identified heterogeneously distributed calcium microdomains in the ER which were correlated w让h the distribution of STIM1 clusters upon ER calcium store depletion. Lastly, GCEPIA1-SNAPer can be used to detect the ER calcium store by high-throughput flow cytometry and confers the ability to study the function of calcium microdomains of the ER.

关 键 词：RATIOMETRIC CALCIUM sensor LOCAL CALCIUM microdomain  Endoplasmic reticulum 

分 类 号：Q[生物学]