creatinetransporter

Creatine transporter refers to a membrane transport protein that mediates the uptake of creatine into cells. In humans, it is encoded by the SLC6A8 gene on the X chromosome, and it belongs to the solute carrier family 6 (SLC6). The protein functions as a sodium- and chloride-dependent symporter, typically comprising multiple transmembrane segments that facilitate creatine transport across the cell membrane in response to the electrochemical gradients of sodium and chloride.

The transporter plays a crucial role in maintaining intracellular creatine pools, which are used to regenerate adenosine triphosphate (ATP) via the phosphocreatine system. This energy buffering is especially important in tissues with high energy demands, such as skeletal muscle and brain. The SLC6A8-encoded transporter is expressed in several tissues, including kidney, brain, and skeletal muscle, where it supports cellular energy homeostasis and normal metabolic function.

Genetic mutations in SLC6A8 cause creatine transporter deficiency (CTD), an X-linked neurodevelopmental disorder. Affected individuals, typically males, often present with intellectual disability, speech and language delays, developmental delay, seizures, and autistic-like features. Brain magnetic resonance spectroscopy frequently shows reduced or absent creatine peaks. Diagnosis is established through genetic testing for pathogenic SLC6A8 variants or corroborating neuroimaging findings. Treatment options are limited; oral creatine supplementation may be ineffective in CTD due to transporter dysfunction, and research continues into alternative therapeutic strategies and supportive care.