Lysosomal-associated transmembrane protein 4B (Lysosome-associated transmembrane protein 4-beta)
1_MTSRT 6_ RVTWP 11_ SPPRP 16_ LPVPA 21_ AAAVA 26_ FGAKG 31_ TDPAE 36_ ARSSR 41_ GIEEA 46_ GPRAH 51_ GRAGR 56_ EPERR 61_ RSRQQ 66_ RRGGL 71_ QARRS 76_ TLLKT 81_ CARAR 86_ ATAPG 91_ AMKMV 96_ APWTR 101_ FYSNS 106_ CCLCC 111_ HVRTG 116_ TILLG 121_ VWYLI 126_ INAVV 131_ LLILL 136_ SALAD 141_ PDQYN 146_ FSSSE 151_ LGGDF 156_ EFMDD 161_ ANMCI 166_ AIAIS 171_ LLMIL 176_ ICAMA 181_ TYGAY 186_ KQRAA 191_ WIIPF 196_ FCYQI 201_ FDFAL 206_ NMLVA 211_ ITVLI 216_ YPNSI 221_ QEYIR 226_ QLPPN 231_ FPYRD 236_ DVMSV 241_ NPTCL 246_ VLIIL 251_ LFISI 256_ ILTFK 261_ GYLIS 266_ CVWNC 271_ YRYIN 276_ GRNSS 281_ DVLVY 286_ VTSND 291_ TTVLL 296_ PPYDD 301_ ATVNG 306_ AAKEP 311_PPPYV
1: Required for optimal lysosomal function (PubMed:21224396). Blocks EGF-stimulated EGFR intraluminal sorting and degradation. Conversely by binding with the phosphatidylinositol 4,5-bisphosphate, regulates its PIP5K1C interaction, inhibits HGS ubiquitination and relieves LAPTM4B inhibition of EGFR degradation (PubMed:25588945). Recruits SLC3A2 and SLC7A5 (the Leu transporter) to the lysosome, promoting entry of leucine and other essential amino acid (EAA) into the lysosome, stimulating activation of proton-transporting vacuolar (V)-ATPase protein pump (V-ATPase) and hence mTORC1 activation (PubMed:25998567). Plays a role as negative regulator of TGFB1 production in regulatory T cells (PubMed:26126825). Binds ceramide and facilitates its exit from late endosome in order to control cell death pathways (PubMed:26280656)