ASCT

ASCT (Alanine Serine Cysteine Transporters) belongs to the SLC1 family and functions as a membrane protein responsible for the transport of neutral amino acids, including ASCT1 (SLC1A4) and ASCT2 (SLC1A5). ASCTs mediate Na⁺-dependent amino acid exchange but do not utilize the Na⁺ gradient as a driving force; instead, they maintain homeostasis by exchanging amino acids between the intracellular and extracellular environments. ASCT1 and ASCT2 exhibit different substrate selectivities, with ASCT1 showing a higher affinity for alanine and serine, whereas ASCT2 can also transport glutamine, playing a crucial role in tumor metabolism. ASCT2 is highly expressed in various tumor tissues, where it facilitates glutamine uptake, supplying nitrogen and energy to rapidly proliferating cancer cells, making it a potential target for cancer therapy. In contrast, ASCT1 is primarily associated with neurological disorders, as mutations in the SLC1A4 gene can lead to intellectual disability, postnatal microcephaly, spasticity, and thinning of the corpus callosum. ASCTs provide new strategies for research in both cancer and neurological diseases^[1].