Transport of Calcium Ions into Mitochondria

Abstract

To uptake calcium ions of mitochondria is of significant functional connotation for cells, because calcium ions in mitochondria are involved in energy production, regulatory signals transfer, and mitochondrial permeability transition pore opening and even programmed cell death of apoptosis, further playing more roles in plant productivity and quality. Cytoplasmic calcium ions access into outer mitochondrial membrane (OMM) from voltage dependent anion-selective channel (VDAC) and were absorbed into inner mitochondrial membrane (IMM) by mitochondrial calcium uniporter (MCU), rapid mitochondrial calcium uptake (RaM) or mitochondrial ryanodine receptor (mRyR). Although both mitochondria and the mechanisms of calcium transport have been extensively studied, but there are still long-standing or even new challenges. Here we review the history and recent discoveries of the mitochondria calcium ions channel complex involved calcium assimilation, and discuss the role of calcium ions into mitochondria.

Keywords: Calcium ions uptake; Channels; Mitochondria; Uniporter..

Fig. (1)

Schematic representation of MCU based on published data [44]. At high calcium ions levels, the EF hands of both MICU2 and M1CU1 are bound with calcium ions, quieting inhibitory of MICU2 and activating stimulatory MICU1, the MCU opens, and calcium is taken up rapidly into the mitochondria.

Fig. (2)

Schematic representation of calcium ion in plant cell under salt stress. Under salt stress, more calcium ions will accumulate in the cells and will go through MCU into mitochondria, and with salt stress the mitochondrial calcium ion concentration will be very high, but high concentration calcium induces the generation of mitochondrial reactive oxygen species, which affect the efficiency of ATP synthesis in mitochondria, resulting in root and leaf due to lack of energy supply, and affect a variety of ion transport and metabolism in plant cell.