Ca2+ Hot Spots on the Mitochondrial Surface Are Generated by Ca2+ Mobilization from Stores, but Not by Activation of Store-Operated Ca2+ Channels

被引：317

作者：

Giacomello, Marta ^{[1
,2
]}

Drago, Ilaria ^{[1
,2
]}

Bortolozzi, Mario ^{[3
]}

Scorzeto, Michele ^{[5
]}

Gianelle, Alessio ^{[4
]}

Pizzo, Paola ^{[1
,2
]}

Pozzan, Tullio ^{[1
,2
,3
]}

机构：

[1] Univ Padua, Dept Biomed Sci, I-35121 Padua, Italy

[2] CNR, Inst Neurosci, I-35121 Padua, Italy

[3] Venetian Inst Mol Med, I-35131 Padua, Italy

[4] Ist Nazl Fis Nucl, I-00044 Frascati, Italy

[5] Univ Padua, Dept Human Anat & Physiol, I-35131 Padua, Italy

来源：

MOLECULAR CELL | 2010年 / 38卷 / 02期

关键词：

ENDOPLASMIC-RETICULUM; INTRACELLULAR CA2+; CALCIUM; DETERMINANTS; APOPTOSIS; DYNAMICS; STIM1;

D O I：

10.1016/j.molcel.2010.04.003

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Although it is widely accepted that mitochondria in living cells can efficiently uptake Ca2+ during stimulation because of their vicinity to microdomains of high [Ca2+], the direct proof of Ca2+ hot spots' existence is still lacking. Thanks to a GFP-based Ca2+ probe localized on the cytosolic surface of the outer mitochondrial membrane, we demonstrate that, upon Ca2+ mobilization, the [Ca2+] in small regions of the mitochondrial surface reaches levels 5- to 10-fold higher than in the bulk cytosol. We also show that the [Ca2+] to which mitochondria are exposed during capacitative Ca2+ influx is similar between near plasma membrane mitochondria and organelles deeply located in the cytoplasm, whereas it is 2- to 3-fold higher in subplasma membrane mitochondria upon activation of voltage-gated Ca2+ channels. These results demonstrate that mitochondria are exposed to Ca2+ hot spots close to the ER but are excluded from the regions where capacitative Ca2+ influx occurs.

引用

页码：280 / 290

页数：11

共 30 条

[1] SOURCE OF NUCLEAR CALCIUM SIGNALS [J].