DNA-directed RNA polymerase I subunit RPA1 (RNA polymerase I subunit A1) (EC 2.7.7.6) (A190) (DNA-directed RNA polymerase I largest subunit) (DNA-directed RNA polymerase I subunit A) (RNA polymerase I 194 kDa subunit) (RPA194)
1_MLISK 6_ NMPWR 11_ RLQGI 16_ SFGMY 21_ SAEEL 26_ KKLSV 31_ KSITN 36_ PRYLD 41_ SLGNP 46_ SANGL 51_ YDLAL 56_ GPADS 61_ KEVCS 66_ TCVQD 71_ FSNCS 76_ GHLGH 81_ IELPL 86_ TVYNP 91_ LLFDK 96_ LYLLL 101_ RGSCL 106_ NCHML 111_ TCPRA 116_ VIHLL 121_ LCQLR 126_ VLEVG 131_ ALQAV 136_ YELER 141_ ILNRF 146_ LEENP 151_ DPSAS 156_ EIREE 161_ LEQYT 166_ TEIVQ 171_ NNLLG 176_ SQGAH 181_ VKNVC 186_ ESKSK 191_ LIALF 196_ WKAHM 201_ NAKRC 206_ PHCKT 211_ GRSVV 216_ RKEHN 221_ SKLTI 226_ TFPAM 231_ VHRTA 236_ GQKDS 241_ EPLGI 246_ EEAQI 251_ GKRGY 256_ LTPTS 261_ AREHL 266_ SALWK 271_ NEGFF 276_ LNYLF 281_ SGMDD 286_ DGMES 291_ RFNPS 296_ VFFLD 301_ FLVVP 306_ PSRYR 311_ PVSRL 316_ GDQMF 321_ TNGQT 326_ VNLQA 331_ VMKDV 336_ VLIRK 341_ LLALM 346_ AQEQK 351_ LPEEV 356_ ATPTT 361_ DEEKD 366_ SLIAI 371_ DRSFL 376_ STLPG 381_ QSLID 386_ KLYNI 391_ WIRLQ 396_ SHVNI 401_ VFDSE 406_ MDKLM 411_ MDKYP 416_ GIRQI 421_ LEKKE 426_ GLFRK 431_ HMMGK 436_ RVDYA 441_ ARSVI 446_ CPDMY 451_ INTNE 456_ IGIPM 461_ VFATK 466_ LTYPQ 471_ PVTPW 476_ NVQEL 481_ RQAVI 486_ NGPNV 491_ HPGAS 496_ MVINE 501_ DGSRT 506_ ALSAV 511_ DMTQR 516_ EAVAK 521_ QLLTP 526_ ATGAP 531_ KPQGT 536_ KIVCR 541_ HVKNG 546_ DILLL 551_ NRQPT 556_ LHRPS 561_ IQAHR 566_ ARILP 571_ EEKVL 576_ RLHYA 581_ NCKAY 586_ NADFD 591_ GDEMN 596_ AHFPQ 601_ SELGR 606_ AEAYV 611_ LACTD 616_ QQYLV 621_ PKDGQ 626_ PLAGL 631_ IQDHM 636_ VSGAS 641_ MTTRG 646_ CFFTR 651_ EHYME 656_ LVYRG 661_ LTDKV 666_ GRVKL 671_ LSPSI 676_ LKPFP 681_ LWTGK 686_ QVVST 691_ LLINI 696_ IPEDH 701_ IPLNL 706_ SGKAK 711_ ITGKA 716_ WVKET 721_ PRSVP 726_ GFNPD 731_ SMCES 736_ QVIIR 741_ EGELL 746_ CGVLD 751_ KAHYG 756_ SSAYG 761_ LVHCC 766_ YEIYG 771_ GETSG 776_ KVLTC 781_ LARLF 786_ TAYLQ 791_ LYRGF 796_ TLGVE 801_ DILVK 806_ PKADV 811_ KRQRI 816_ IEEST 821_ HCGPQ 826_ AVRAA 831_ LNLPE 836_ AASYD 841_ EVRGK 846_ WQDAH 851_ LGKDQ 856_ RDFNM 861_ IDLKF 866_ KEEVN 871_ HYSNE 876_ INKAC 881_ MPFGL 886_ HRQFP 891_ ENSLQ 896_ MMVQS 901_ GAKGS 906_ TVNTM 911_ QISCL 916_ LGQIE 921_ LEGRR 926_ PPLMA 931_ SGKSL 936_ PCFEP 941_ YEFTP 946_ RAGGF 951_ VTGRF 956_ LTGIK 961_ PPEFF 966_ FHCMA 971_ GREGL 976_ VDTAV 981_ KTSRS 986_ GYLQR 991_ CIIKH 996_ LEGLV 1001_ VQYDL 1006_ TVRDS 1011_ DGSVV 1016_ QFLYG 1021_ EDGLD 1026_ IPKTQ 1031_ FLQPK 1036_ QFPFL 1041_ ASNYE 1046_ VIMKS 1051_ QHLHE 1056_ VLSRA 1061_ DPKKA 1066_ LHHFR 1071_ AIKKW 1076_ QSKHP 1081_ NTLLR 1086_ RGAFL 1091_ SYSQK 1096_ IQEAV 1101_ KALKL 1106_ ESENR 1111_ NGRSP 1116_ GTQEM 1121_ LRMWY 1126_ ELDEE 1131_ SRRKY 1136_ QKKAA 1141_ ACPDP 1146_ SLSVW 1151_ RPDIY 1156_ FASVS 1161_ ETFET 1166_ KVDDY 1171_ SQEWA 1176_ AQTEK 1181_ SYEKS 1186_ ELSLD 1191_ RLRTL 1196_ LQLKW 1201_ QRSLC 1206_ EPGEA 1211_ VGLLA 1216_ AQSIG 1221_ EPSTQ 1226_ MTLNT 1231_ FHFAG 1236_ RGEMN 1241_ VTLGI 1246_ PRLRE 1251_ ILMVA 1256_ SANIK 1261_ TPMMS 1266_ VPVLN 1271_ TKKAL 1276_ KRVKS 1281_ LKKQL 1286_ TRVCL 1291_ GEVLQ 1296_ KIDVQ 1301_ ESFCM 1306_ EEKQN 1311_ KFQVY 1316_ QLRFQ 1321_ FLPHA 1326_ YYQQE 1331_ KCLRP 1336_ EDILR 1341_ FMETR 1346_ FFKLL 1351_ MESIK 1356_ KKNNK 1361_ ASAFR 1366_ NVNTR 1371_ RATQR 1376_ DLDNA 1381_ GELGR 1386_ SRGEQ 1391_ EGDEE 1396_ EEGHI 1401_ VDAEA 1406_ EEGDA 1411_ DASDA 1416_ KRKEK 1421_ QEEEV 1426_ DYESE 1431_ EEEER 1436_ EGEEN 1441_ DDEDM 1446_ QEERN 1451_ PHREG 1456_ ARKTQ 1461_ EQDEE 1466_ VGLGT 1471_ EEDPS 1476_ LPALL 1481_ TQPRK 1486_ PTHSQ 1491_ EPQGP 1496_ EAMER 1501_ RVQAV 1506_ REIHP 1511_ FIDDY 1516_ QYDTE 1521_ ESLWC 1526_ QVTVK 1531_ LPLMK 1536_ INFDM 1541_ SSLVV 1546_ SLAHG 1551_ AVIYA 1556_ TKGIT 1561_ RCLLN 1566_ ETTNN 1571_ KNEKE 1576_ LVLNT 1581_ EGINL 1586_ PELFK 1591_ YAEVL 1596_ DLRRL 1601_ YSNDI 1606_ HAIAN 1611_ TYGIE 1616_ AALRV 1621_ IEKEI 1626_ KDVFA 1631_ VYGIA 1636_ VDPRH 1641_ LSLVA 1646_ DYMCF 1651_ EGVYK 1656_ PLNRF 1661_ GIRSN 1666_ SSPLQ 1671_ QMTFE 1676_ TSFQF 1681_ LKQAT 1686_ MLGSH 1691_ DELRS 1696_ PSACL 1701_ VVGKV 1706_ VRGGT 1711_GLFEL
1: Catalytic core component of RNA polymerase I (Pol I), a DNA-dependent RNA polymerase which synthesizes ribosomal RNA precursors using the four ribonucleoside triphosphates as substrates. Transcribes 47S pre-rRNAs from multicopy rRNA gene clusters, giving rise to 5.8S, 18S and 28S ribosomal RNAs (PubMed:11250903, PubMed:11283244, PubMed:16858408, PubMed:34671025, PubMed:34887565, PubMed:36271492). Pol I-mediated transcription cycle proceeds through transcription initiation, transcription elongation and transcription termination stages. During transcription initiation, Pol I pre-initiation complex (PIC) is recruited by the selectivity factor 1 (SL1/TIF-IB) complex bound to the core promoter that precedes an rDNA repeat unit. The PIC assembly bends the promoter favoring the formation of the transcription bubble and promoter escape. Once the polymerase has escaped from the promoter it enters the elongation phase during which RNA is actively polymerized, based on complementarity with the template DNA strand. Highly processive, assembles in structures referred to as 'Miller trees' where many elongating Pol I complexes queue and transcribe the same rDNA coding regions. At terminator sequences downstream of the rDNA gene, PTRF interacts with Pol I and halts Pol I transcription leading to the release of the RNA transcript and polymerase from the DNA (PubMed:11250903, PubMed:11283244, PubMed:16858408, PubMed:34671025, PubMed:34887565, PubMed:36271492). Forms Pol I active center together with the second largest subunit POLR1B/RPA2. Appends one nucleotide at a time to the 3' end of the nascent RNA, with POLR1A/RPA1 contributing a Mg(2+)-coordinating DxDGD motif, and POLR1B/RPA2 participating in the coordination of a second Mg(2+) ion and providing lysine residues believed to facilitate Watson-Crick base pairing between the incoming nucleotide and the template base. Typically, Mg(2+) ions direct a 5' nucleoside triphosphate to form a phosphodiester bond with the 3' hydroxyl of the preceding nucleotide of the nascent RNA, with the elimination of pyrophosphate. Has proofreading activity: Pauses and backtracks to allow the cleavage of a missincorporated nucleotide via POLR1H/RPA12. High Pol I processivity is associated with decreased transcription fidelity (By similarity) (PubMed:11250903, PubMed:11283244, PubMed:16858408, PubMed:34671025, PubMed:34887565, PubMed:36271492)