B(0,+)-type amino acid transporter 1

B(0,+)-type amino acid transporter 1 (B0AT1), also known as SLC6A19, is a protein that in humans is encoded by the SLC6A19 gene. It is a member of the solute carrier family 6, which includes neurotransmitter transporters, ion transporters, and amino acid transporters. B0AT1 is primarily expressed in the kidney and intestine, where it plays a crucial role in the absorption of neutral amino acids.

Structure

The B0AT1 protein is a multi-pass membrane protein, meaning it crosses the cell membrane multiple times. It is composed of 12 transmembrane domains with both the N- and C- termini located intracellularly. The protein also contains several potential glycosylation and phosphorylation sites, which may be involved in its regulation.

Function

B0AT1 functions as a sodium-dependent and chloride-independent transporter of neutral amino acids. This means it uses the sodium gradient across the cell membrane to drive the uptake of amino acids into the cell. The transporter has a broad substrate specificity, being able to transport a variety of neutral amino acids including leucine, isoleucine, valine, phenylalanine, tyrosine, tryptophan, methionine, and others.

Clinical significance

Mutations in the SLC6A19 gene can lead to Hartnup disorder, a metabolic condition characterized by the impaired absorption of certain amino acids in the gut and kidney. Symptoms of Hartnup disorder can include skin rashes, neurological symptoms, and aminoaciduria.

See also

• Solute carrier family
• Amino acid transporter
• Hartnup disorder