SLC7A11
Description
The SLC7A11 (solute carrier family 7 member 11) is a protein-coding gene located on chromosome 4.
The SLC7A11 gene encodes a sodium-independent cystine-glutamate antiporter, also known as xCT. It forms a heterodimer with SLC3A2, creating system Xc-, the functional cystine-glutamate antiporter. SLC7A11 is critical for glutathione production in nervous and non-nervous tissues. In the nervous system, it regulates synaptic activity by stimulating extrasynaptic receptors and facilitating nonvesicular glutamate release. SLC7A11 is highly expressed by astrocytes and couples cystine uptake with glutamate release. Its expression is detected throughout the brain, with higher levels in the basolateral amygdala, retina, and prefrontal cortex. Inhibition of system Xc- affects behavior, indicating its importance in excitatory signaling.
SLC7A11 forms a heterodimer with SLC3A2, acting as an antiporter that exchanges extracellular L-cystine for intracellular L-glutamate across the cell membrane. It facilitates L-cystine uptake for redox balance, glutathione synthesis, and cell protection against oxidative stress. This sodium-independent, electroneutral transport occurs with a 1:1 stoichiometry, driven by intracellular L-glutamate concentration and L-cystine reduction. SLC7A11 also mediates L-kynurenine import for anti-ferroptotic signaling, N-acetyl-L-cysteine uptake in the placenta, and can transport L-aspartate in vitro. This protein may be involved in astrocyte and meningeal cell proliferation during development, providing neuroprotection by promoting glutathione delivery to immature neurons. It directly controls pheomelanin pigment production.
SLC7A11 is also known as CCBR1, xCT.
