ATP-dependent low-affinity peptide transporter which translocates a broad spectrum of peptides from the cytosol to the lysosomal lumen for degradation. Displays a broad peptide length specificity from 6-mer up to at least 59-mer peptides with an optimum of 23-mers. Binds and transports smaller and larger peptides with the same affinity. Favors positively charged, aromatic or hydrophobic residues in the N- and C-terminal positions whereas negatively charged residues as well as asparagine and methionine are not favored.
|Gene References into Functions
- The structure of the unique domain of TAPL, is reported. PMID: 24013930
- LAMP proteins retain TAPL on the limiting membrane of endosomes and prevent its sorting to intraluminal vesicles. PMID: 22641697
- These results suggest that TAPL may be localized to the microdomains (lipid rafts) of lysosomal membranes enriched in cholesterol. PMID: 21212514
- By dissecting ABCB9, distinct functions were assigned to the core complex and the extra N-terminal transmembrane domain. PMID: 20377823
- is part of the peptide-loading complex in the classic route of antigen processing via major histocompatibility complex class I molecules PMID: 15863492
- These findings suggest that the transport activity of hTAPL is important for conferring high valinomycin-sensitive phenotype to yeast. PMID: 16554024
- the TAPL-specific translocation of peptides into isolated lysosomes strictly requires ATP hydrolysis PMID: 17977821
- The ATP-binding of TAPL required Mg(2+), and was observed at neutral pH. Chemical cross-linking experiments suggested that TAPL forms a homodimer in the membrane and under the solubilized conditions. PMID: 18175933
- analysis of lipid activation of the lysosomal transport complex ABCB9 PMID: 18434309
- These results suggest that the sorting signal for lysosomes is present within the amino-terminal transmembrane domain (Met(1)-Arg(141)) of the TAPL molecule. PMID: 18952056
||Lysosome membrane; Multi-pass membrane protein.
||ABC transporter superfamily, ABCB family, MHC peptide exporter (TC 3.A.1.209) subfamily
||Highly expressed in testis, and at moderate levels in brain, spinal cord, and thyroid. Not expressed in monocytes but strongly expressed during differentiation of monocytes to dendritic cells and macrophages.