Transporter that mediates resorption of neutral amino acids across the apical membrane of renal and intestinal epithelial cells. This uptake is sodium-dependent and chloride-independent. Requires CLTRN in kidney or ACE2 in intestine for cell surface expression and amino acid transporter activity. L-alanine(in) + Na(+)(in) = L-alanine(out) + Na(+)(out) L-cysteine(in) + Na(+)(in) = L-cysteine(out) + Na(+)(out) L-glutamine(in) + Na(+)(in) = L-glutamine(out) + Na(+)(out) glycine(in) + Na(+)(in) = glycine(out) + Na(+)(out) L-isoleucine(in) + Na(+)(in) = L-isoleucine(out) + Na(+)(out) L-leucine(in) + Na(+)(in) = L-leucine(out) + Na(+)(out) L-methionine(in) + Na(+)(in) = L-methionine(out) + Na(+)(out) L-phenylalanine(in) + Na(+)(in) = L-phenylalanine(out) + Na(+)(out) L-serine(in) + Na(+)(in) = L-serine(out) + Na(+)(out) L-tryptophan(in) + Na(+)(in) = L-tryptophan(out) + Na(+)(out) L-tyrosine(in) + Na(+)(in) = L-tyrosine(out) + Na(+)(out) L-valine(in) + Na(+)(in) = L-valine(out) + Na(+)(out) Interacts in a tissue-specific manner with ACE2 in small intestine and with CLTRN in the kidney. Interacts with CLTRN; this interaction is required for trafficking of SLC6A19 to the plasma membrane and for its catalytic activation in kidneys. Interacts with ACE2; this interaction is required for trafficking of SLC6A19 to the plasma membrane and for its catalytic activation in intestine. Interacts with ANPEP; the interaction positively regulates its amino acid transporter activity (By similarity). Belongs to the sodium:neurotransmitter symporter (SNF) (TC 2.A.22) family. SLC6A19 subfamily.