7SK snRNA methylphosphate capping enzyme (MePCE) (EC 2.1.1.-) (Bicoid-interacting protein 3 homolog) (Bin3 homolog)
1_MIEMA 6_ AEKEP 11_ FLVPA 16_ PPPPL 21_ KDESG 26_ GGGGP 31_ TVPPH 36_ QEAAS 41_ GELRG 46_ GTERG 51_ PGRCA 56_ PSAGS 61_ PAAAV 66_ GRESP 71_ GAAAT 76_ SSSGP 81_ QAQQH 86_ RGGGP 91_ QAQSH 96_ GEARL 101_ SDPPG 106_ RAAPP 111_ DVGEE 116_ RRGGG 121_ GTELG 126_ PPAPP 131_ RPRNG 136_ YQPHR 141_ PPGGG 146_ GGKRR 151_ NSCNV 156_ GGGGG 161_ GFKHP 166_ AFKRR 171_ RRVNS 176_ DCDSV 181_ LPSNF 186_ LLGGN 191_ IFDPL 196_ NLNSL 201_ LDEEV 206_ SRTLN 211_ AETPK 216_ SSPLP 221_ AKGRD 226_ PVEIL 231_ IPKDI 236_ TDPLS 241_ LNTCT 246_ DEGHV 251_ VLASP 256_ LKTGR 261_ KRHRH 266_ RGQHH 271_ QQQQA 276_ AGGSE 281_ SHPVP 286_ PTAPL 291_ TPLLH 296_ GEGAS 301_ QQPRH 306_ RGQNR 311_ DAPQP 316_ YELNT 321_ AINCR 326_ DEVVS 331_ PLPSA 336_ LQGPS 341_ GSLSA 346_ PPAAS 351_ VISAP 356_ PSSSS 361_ RHRKR 366_ RRTSS 371_ KSEAG 376_ ARGGG 381_ QGSKE 386_ KGRGS 391_ WGGRH 396_ HHHHP 401_ LPAAG 406_ FKKQQ 411_ RKFQY 416_ GNYCK 421_ YYGYR 426_ NPSCE 431_ DGRLR 436_ VLKPE 441_ WFRGR 446_ DVLDL 451_ GCNVG 456_ HLTLS 461_ IACKW 466_ GPSRM 471_ VGLDI 476_ DSRLI 481_ HSARQ 486_ NIRHY 491_ LSEEL 496_ RLPPQ 501_ TLEGD 506_ PGAEG 511_ EEGTT 516_ TVRKR 521_ SCFPA 526_ SLTAS 531_ RGPIA 536_ APQVP 541_ LDGAD 546_ TSVFP 551_ NNVVF 556_ VTGNY 561_ VLDRD 566_ DLVEA 571_ QTPEY 576_ DVVLC 581_ LSLTK 586_ WVHLN 591_ WGDEG 596_ LKRMF 601_ RRIYR 606_ HLRPG 611_ GILVL 616_ EPQPW 621_ SSYGK 626_ RKTLT 631_ ETIYK 636_ NYYRI 641_ QLKPE 646_ QFSSY 651_ LTSPD 656_ VGFSS 661_ YELVA 666_ TPHNT 671_ SKGFQ 676_ RPVYL 681_FHKAR
1: S-adenosyl-L-methionine-dependent methyltransferase that adds a methylphosphate cap at the 5'-end of 7SK snRNA (7SK RNA), leading to stabilize it (PubMed:17643375, PubMed:19906723, PubMed:30559425). Also has a non-enzymatic function as part of the 7SK RNP complex: the 7SK RNP complex sequesters the positive transcription elongation factor b (P-TEFb) in a large inactive 7SK RNP complex preventing RNA polymerase II phosphorylation and subsequent transcriptional elongation (PubMed:17643375). The 7SK RNP complex also promotes snRNA gene transcription by RNA polymerase II via interaction with the little elongation complex (LEC) (PubMed:28254838). In the 7SK RNP complex, MEPCE is required to stabilize 7SK RNA and facilitate the assembly of 7SK RNP complex (PubMed:19906723, PubMed:38100593). MEPCE has a non-enzymatic function in the 7SK RNP complex; interaction with LARP7 within the 7SK RNP complex occluding its catalytic center (PubMed:19906723). Also required for stability of U6 snRNAs (PubMed:38100593)