Y+L amino acid transporter 1 (y+LAT1) (SLC7A7)

Y+L amino acid transporter 1 (SLC7A7) is a transmembrane protein that functions as the light subunit of a heteromeric amino acid transporter complex, primarily responsible for the sodium-independent efflux of cationic amino acids like arginine, lysine, and ornithine in exchange for neutral amino acids and sodium [1, 2]. It is highly expressed in the basolateral membranes of intestinal and renal epithelial cells, as well as in macrophages, where it regulates the intracellular availability of arginine for nitric oxide production and immune signaling [3, 4]. Mutations in the SLC7A7 gene cause Lysinuric Protein Intolerance (LPI), a multi-systemic metabolic disorder characterized by impaired dibasic amino acid transport, leading to urea cycle dysfunction and severe immune-related complications [5]. In macrophages, SLC7A7 deficiency results in an altered inflammatory phenotype, contributing to the development of pulmonary alveolar proteinosis and hemophagocytic lymphohistiocytosis [3, 4]. Current therapeutic approaches focus on dietary management and supplementation with citrulline to mitigate the metabolic consequences of the transporter defect [5]. Additionally, research into the modulation of SLC7A7 in macrophages suggests its potential as a target for treating inflammatory conditions and certain cancers where arginine metabolism is dysregulated [4].

Other names

Solute carrier family 7 member 7y+LAT1y+L amino acid transporter 1Lysinuric protein intolerance proteinMOP-2Monocyte amino acid permease 2

Substrate supplementation to bypass transport defects and nitrogen scavenging to manage hyperammonemia.