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A protein that mediates the transport of one molecule or ion through a membrane without known coupling to the transport of any other molecule or ion.
Farlex Partner Medical Dictionary © Farlex 2012
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The existence of the mitochondrial [Ca.sup.2+] uniporter, which dynamically buffers physiological [Ca.sup.2+] concentrations in mitochondria, has been confirmed in this shrimp species (data not shown); however, to date there is no information that confirms the existence of proteins such as calcium antiporters either 2[N.sub.a+] or 2[H.sub.+] in crustaceans.
Hang, "Role of mitochondrial calcium uniporter in early brain injury after experimental subarachnoid hemorrhage," Molecular Neurobiology, vol.
The transport, across the inner membrane of Ca++ from the IMS to the mitochondrial matrix, is mainly contributed by the mitochondrial calcium uniporter (MCU), an ion channel that selectively drives the [Ca.sup.2+] entry into the matrix.
The mechanisms underlying CaMKII-mediated apoptosis have been attributed to direct phosphorylation of calcineurin at Ser197 [274] and subsequent repression of calcineurin/NFAT signaling [275], enhancing voltage-gated [Ca.sup.2+] channel- (Cav1.2-) dependent calcium overload [276], or phosphorylation of mitochondrial [Ca.sup.2+] uniporter (MCU) at Ser57/Ser92 and increasing MCU current, leading to mPTP opening and cell death [277].
Saha et al., "Probing novel roles of the mitochondrial uniporter in ovarian cancer cells using nanoparticles," The Journal of Biological Chemistry, vol.
Second, mitochondrial reenergization during reoxygenation allows the recovery of the membrane potential that drives the [Ca.sup.2+] uptake into the mitochondria through the mitochondrial [Ca.sup.2+] uniporter (MCU) channel and subsequently induces m[Ca.sup.2+] overload [4].
Active mitochondrial [Ca.sup.2+] uptake is mediated by a specific transporter, namely the mitochondrial [Ca.sup.2+] uniporter (MCU), which transfers [Ca.sup.2+] through the inner mitochondrial membrane (IMM) at the expense of the proton gradient generated by the mitochondrial respiratory chain.
Zazueta, "Inhibition of the mitochondrial calcium uniporter by the oxo-bridged dinuclear ruthenium amine complex (Ru360) prevents from irreversible injury in postischemic rat heart," The FEBS Journal, vol.
In addition, activation of AMPA receptors also contributes to the influx of [Ca.sup.2+] and [Na.sup.+], which leads to mitochondrial [Ca.sup.2+] loading, and this process can be blocked by ruthenium red, a mitochondrial calcium uniporter blocker [18].
Some of the ion channels located on the outer and inner membrane include voltage dependent anion channel (VDAC), [Ca.sup.2+] uniporter, permeability transition pore (PTP), calcium-activated potassium channels ([formula not reproducible]), ATP-sensitive potassium channels ([K.sub.ATP]), and inner membrane anion channel (IMAC) [51].
Meanwhile, the mechanisms of removing [Ca.sup.2+] are determined by the plasma membrane [Ca.sup.2+] ATPase (PMCA), which mediates [Ca.sup.2+] extrusion across the plasma membrane into the cytoplasm, the sarcoplasmic/endoplasmic reticulum [Ca.sup.2+] ATPase (SERCA), which reintroduces [Ca.sup.2+] into the ER/SR, [Na.sup.+]/[Ca.sup.2+] exchanger (NCX) that involves the clearance of [Ca.sup.2+] through its exchange by [Na.sup.+], and the mitochondrial [Ca.sup.2+] uniporter (MCU) that transports [Ca.sup.2+] into the mitochondria [103, 104].
Mitochondrial [Ca.sup.2+] Uniporter (MCU)/Mitochondrial [Ca.sup.2+] Uptake 1 (MICU1)/MICU2.