Endosomal/lysosomal potassium channel TMEM175 (Transmembrane protein 175) (hTMEM175)
1_MSQPR 6_ TPEQA 11_ LDTPG 16_ DCPPG 21_ RRDED 26_ AGEGI 31_ QCSQR 36_ MLSFS 41_ DALLS 46_ IIATV 51_ MILPV 56_ THTEI 61_ SPEQQ 66_ FDRSV 71_ QRLLA 76_ TRIAV 81_ YLMTF 86_ LIVTV 91_ AWAAH 96_ TRLFQ 101_ VVGKT 106_ DDTLA 111_ LLNLA 116_ CMMTI 121_ TFLPY 126_ TFSLM 131_ VTFPD 136_ VPLGI 141_ FLFCV 146_ CVIAI 151_ GVVQA 156_ LIVGY 161_ AFHFP 166_ HLLSP 171_ QIQRS 176_ AHRAL 181_ YRRHV 186_ LGIVL 191_ QGPAL 196_ CFAAA 201_ IFSLF 206_ FVPLS 211_ YLLMV 216_ TVILL 221_ PYVSK 226_ VTGWC 231_ RDRLL 236_ GHREP 241_ SAHPV 246_ EVFSF 251_ DLHEP 256_ LSKER 261_ VEAFS 266_ DGVYA 271_ IVATL 276_ LILDI 281_ CEDNV 286_ PDPKD 291_ VKERF 296_ SGSLV 301_ AALSA 306_ TGPRF 311_ LAYFG 316_ SFATV 321_ GLLWF 326_ AHHSL 331_ FLHVR 336_ KATRA 341_ MGLLN 346_ TLSLA 351_ FVGGL 356_ PLAYQ 361_ QTSAF 366_ ARQPR 371_ DELER 376_ VRVSC 381_ TIIFL 386_ ASIFQ 391_ LAMWT 396_ TALLH 401_ QAETL 406_ QPSVW 411_ FGGRE 416_ HVLMF 421_ AKLAL 426_ YPCAS 431_ LLAFA 436_ STCLL 441_ SRFSV 446_ GIFHL 451_ MQIAV 456_ PCAFL 461_ LLRLL 466_ VGLAL 471_ ATLRV 476_ LRGLA 481_ RPEHP 486_ PPAPT 491_ GQDDP 496_QSQLL
1: Proton-activated proton channel that catalyzes proton efflux from endosomes and lysosomes to maintain a steady-state pH (PubMed:35333573, PubMed:35750034, PubMed:37390818). Activated at low pH (under pH 4.6) by luminal side protons: selectively mediates lysosomal proton release from lysosomes, eliciting a proton leak that balances V-ATPase activity to maintain pH homeostasis (PubMed:35750034). Regulation of lumenal pH stability is required for autophagosome-lysosome fusion (PubMed:26317472, PubMed:32267231). Also acts as a potassium channel at higher pH, regulating potassium conductance in endosomes and lysosomes (PubMed:26317472, PubMed:28723891, PubMed:32228865, PubMed:32267231, PubMed:33505021). Constitutes the pore-forming subunit of the lysoK(GF) complex, a complex activated by extracellular growth factors (PubMed:33505021). The lysoK(GF) complex is composed of TMEM175 and AKT (AKT1, AKT2 or AKT3), a major target of growth factor receptors: in the complex, TMEM175 channel is opened by conformational changes by AKT, leading to its activation (PubMed:33505021). The lysoK(GF) complex is required to protect neurons against stress-induced damage (PubMed:33505021)