Wo genau wird in den Mitochondrien das Calcium gespeichert?

in den Granula?

Answer 1

[jort93]

https://www.ncbi.nlm.nih.gov/books/NBK28135/

Within cells, the major calcium storing, buffering and signaling organelle appears to be the ER or, as discussed below, a specialized compartment of it. Other specialized structures that may be involved in calcium storage include the mitochondria and the nucleus. There was, for a time, a rather widely held belief that mitochondria represented the major source of signaling calcium that was released by hormone or neurotransmitter receptor activation. Perhaps the most convincing demonstration that mitochondria were not involved primarily in hormonal responses came with the discovery of inositol 1,4,5-trisphosphate (IP₃, or I(1,4,5)P₃ to distinguish it from other positional isomers), as the mediator of intracellular release of Ca²⁺ (reviewed in [4] and discussed below; see also Chap. 21). IP₃ was clearly shown to act only on nonmitochondrial stores. As the default for nonmitochondrial calcium storage was thought to be the ER, this was taken as evidence that the ER was the critical storage site for signaling calcium.

Calcium is stored at other significant sites in the cell

These include secretory granules and the nucleus. The Ca²⁺ in secretory granules generally has been considered to be relatively inert and to function largely in a structural capacity. However, evidence has suggested that this Ca²⁺ can be released during cell stimulation and can participate in the control of secretion.

Also, am meisten nutzbares calcium wird im Endoplasmatischen Retikulum gespeichert, aber auch etwas in den Granula und dem nucleus.

Comments

[sglpd]

vielen Dank!