SLC15A4

Description

The SLC15A4 (solute carrier family 15 member 4) is a protein-coding gene located on chromosome 12.

Solute carrier family 15, member 4 is a protein in humans that is encoded by the SLC15A4 gene.

SLC15A4, also known as Peptide transporter 4, Peptide/histidine transporter 1, is a proton-coupled amino-acid transporter that moves L-histidine and some di- and tripeptides from inside the lysosome to the cytosol. It plays a crucial role in innate immune response by transporting a variety of di- and tripeptides, including carnosine and some peptidoglycans. The transporter's activity is pH-dependent and is most efficient in the acidic lysosomal environment. SLC15A4 is involved in the detection of microbial pathogens by toll-like receptors (TLRs) and NOD-like receptors (NLRs), likely by transporting bacterial peptidoglycans across the endolysosomal membrane. It facilitates the transport of specific bacterial peptidoglycans, such as muramyl dipeptide (MDP), the NOD2 ligand, and L-alanyl-gamma-D-glutamyl-meso-2,6-diaminoheptanedioate (tri-DAP), the NOD1 ligand. SLC15A4 is necessary for TLR7, TLR8, and TLR9-mediated type I interferon (IFN-I) production in plasmacytoid dendritic cells (pDCs). Apart from its transporter activity, it promotes the recruitment of innate immune adapter TASL to the endolysosome downstream of TLR7, TLR8, and TLR9. This TASL recruitment leads to the specific recruitment and activation of IRF5. SLC15A4 is also essential for isotype class switch recombination to IgG2c isotype in response to TLR9 stimulation. It is required for mast cell secretory-granule homeostasis by limiting mast cell functions and inflammatory responses. SLC15A4 interacts with TASL, leading to TASL recruitment to the endolysosome.

SLC15A4 is also known as FP12591, PHT1, PTR4.

Associated Diseases

WES Whole Exome Sequencing