5'-3' exonuclease PLD4 (EC 3.1.16.1) (Choline phosphatase 4) (Phosphatidylcholine-hydrolyzing phospholipase D4) (Phospholipase D family member 4) (Phospholipase D4) (PLD 4)
1_MLKPL 6_ WKAAV 11_ APTWP 16_ CSMPP 21_ RRPWD 26_ REAGT 31_ LQVLG 36_ ALAVL 41_ WLGSV 46_ ALICL 51_ LWQVP 56_ RPPTW 61_ GQVQP 66_ KDVPR 71_ SWEHG 76_ SSPAW 81_ EPLEA 86_ EARQQ 91_ RDSCQ 96_ LVLVE 101_ SIPQD 106_ LPSAA 111_ GSPSA 116_ QPLGQ 121_ AWLQL 126_ LDTAQ 131_ ESVHV 136_ ASYYW 141_ SLTGP 146_ DIGVN 151_ DSSSQ 156_ LGEAL 161_ LQKLQ 166_ QLLGR 171_ NISLA 176_ VATSS 181_ PTLAR 186_ TSTDL 191_ QVLAA 196_ RGAHV 201_ RQVPM 206_ GRLTR 211_ GVLHS 216_ KFWVV 221_ DGRHI 226_ YMGSA 231_ NMDWR 236_ SLTQV 241_ KELGA 246_ VIYNC 251_ SHLAQ 256_ DLEKT 261_ FQTYW 266_ VLGVP 271_ KAVLP 276_ KTWPQ 281_ NFSSH 286_ FNRFQ 291_ PFHGL 296_ FDGVP 301_ TTAYF 306_ SASPP 311_ ALCPQ 316_ GRTRD 321_ LEALL 326_ AVMGS 331_ AQEFI 336_ YASVM 341_ EYFPT 346_ TRFSH 351_ PPRYW 356_ PVLDN 361_ ALRAA 366_ AFGKG 371_ VRVRL 376_ LVGCG 381_ LNTDP 386_ TMFPY 391_ LRSLQ 396_ ALSNP 401_ AANVS 406_ VDVKV 411_ FIVPV 416_ GNHSN 421_ IPFSR 426_ VNHSK 431_ FMVTE 436_ KAAYI 441_ GTSNW 446_ SEDYF 451_ SSTAG 456_ VGLVV 461_ TQSPG 466_ AQPAG 471_ ATVQE 476_ QLRQL 481_ FERDW 486_ SSRYA 491_ VGLDG 496_ QAPGQ 501_DCVWQ
1: 5'->3' exonuclease that hydrolyzes the phosphodiester bond of single-stranded DNA (ssDNA) and RNA molecules to form nucleoside 3'-monophosphates and 5'-end 5'-hydroxy deoxyribonucleotide/ribonucleotide fragments (PubMed:30111894, PubMed:34620855, PubMed:38537643, PubMed:39423811). Partially redundant with PLD3, can cleave all four nucleotides displaying higher efficiency for ssDNA and RNA fragments initiated with uridine and guanosine residues and lower efficiency for cytidine-initiated substrates (PubMed:30111894, PubMed:34620855, PubMed:38537643, PubMed:39423811). As a result, it does not always degrade polynucleotides to the single nucleotide level, it can stall at specific sites sparing certain fragments from exonucleolytic degradation (PubMed:30111894, PubMed:34620855, PubMed:38537643, PubMed:39423811). Processes self and pathogenic ssDNA and RNA molecules that reach the endolysosomal compartment via phagocytosis or autophagy and may serve as 'danger' signals for recognition by innate immune receptors such as toll-like receptors (TLRs) (PubMed:38697119). Degrades mitochondrial CpG-rich ssDNA fragments to prevent TLR9 activation and autoinflammatory response, but it can cleave viral RNA to generate ligands for TLR7 activation and initiate antiviral immune responses (PubMed:38697119). In plasmacytoid dendritic cells, it cooperates with endonuclease RNASET2 to release 2',3'-cyclic guanosine monophosphate (2',3'-cGMP), a potent stimulatory ligand for TLR7 (PubMed:38697119). Produces 2',3'-cGMPs and cytidine-rich RNA fragments that occupy TLR7 ligand-binding pockets and trigger a signaling-competent state (PubMed:38697119). Can exert polynucleotide phosphatase activity toward 5'-phosphorylated ssDNA substrates although at a slow rate (PubMed:38537643). Transphosphatidylase that catalyzes the exchange with R to S stereo-inversion of the glycerol moiety between (S,R)-lysophosphatidylglycerol (LPG) and monoacylglycerol (MAG) substrates to yield (S,S)-bis(monoacylglycero)phosphate (BMP) (PubMed:39423811). Can synthesize a variety of (S,S)-BMPs representing the main phospholipid constituent of lysosomal intralumenal vesicle (ILV) membranes that bind acid hydrolases for lipid degradation (PubMed:39423811). Regulates the homeostasis and interorganellar communication of the endolysosomal system with an overall impact on cellular removal of dysfunctional organelles via autophagy as well as proper protein and lipid turnover. May play a role in myotube formation in response to ER stress (By similarity)