Chemistry Reference
In-Depth Information
FIGURE 11.6
A schematic representation of the transport of Ca
2
þ
in and out of mitochondria. The cartoon shows all the Ca
2
þ
transporters,
and stresses the activation of matrix dehydrogenases. The permeability transition pore (PTP) is enclosed in a dashed box because its role in
Ca
2
þ
release is not established. Abbreviations: AcetylCoA, acetyl-coenzyme A;
a
KGDH,
a
-ketoglutarate dehydrogenase; NAD-IDH, NAD
þ
-
dependent isocitrate dehydrogenase; PDH, pyruvate dehydrogenase; TCA cycle, tricarboxylic acid cycle.
(From
Carafoli, 2003
. Copyright
2003, with permission from Elsevier.)
FIGURE 11.7
The microdomain concept of mitochondrial Ca
2
þ
transport. Ca
2
þ
penetrating from outside or released from the ER generates
restricted domains of high Ca
2
þ
concentration (20
m
M or more), adequate to activate the low-affinity Ca
2
þ
uptake system of neighboring
mitochondria. The Ca
2
þ
-releasing agonist shown is InsP
3
; however, other agonists acting on different channels (e.g., cADPr) also generate the
Ca
2
þ
hotspots.
(From
Carafoli, 2002
. Copyright, 2002, National Academy of Sciences, USA.)
