SUMO-activating enzyme subunit 1 (Ubiquitin-like 1-activating enzyme E1A) [Cleaved into: SUMO-activating enzyme subunit 1, N-terminally processed]
1_MVEKE 6_ EAGGG 11_ ISEEE 16_ AAQYD 21_ RQIRL 26_ WGLEA 31_ QKRLR 36_ ASRVL 41_ LVGLK 46_ GLGAE 51_ IAKNL 56_ ILAGV 61_ KGLTM 66_ LDHEQ 71_ VTPED 76_ PGAQF 81_ LIRTG 86_ SVGRN 91_ RAEAS 96_ LERAQ 101_ NLNPM 106_ VDVKV 111_ DTEDI 116_ EKKPE 121_ SFFTQ 126_ FDAVC 131_ LTCCS 136_ RDVIV 141_ KVDQI 146_ CHKNS 151_ IKFFT 156_ GDVFG 161_ YHGYT 166_ FANLG 171_ EHEFV 176_ EEKTK 181_ VAKVS 186_ QGVED 191_ GPDTK 196_ RAKLD 201_ SSETT 206_ MVKKK 211_ VVFCP 216_ VKEAL 221_ EVDWS 226_ SEKAK 231_ AALKR 236_ TTSDY 241_ FLLQV 246_ LLKFR 251_ TDKGR 256_ DPSSD 261_ TYEED 266_ SELLL 271_ QIRND 276_ VLDSL 281_ GISPD 286_ LLPED 291_ FVRYC 296_ FSEMA 301_ PVCAV 306_ VGGIL 311_ AQEIV 316_ KALSQ 321_ RDPPH 326_ NNFFF 331_ FDGMK 336_ GNGIV 341_ECLGP
1: The heterodimer acts as an E1 ligase for SUMO1, SUMO2, SUMO3, and probably SUMO4. It mediates ATP-dependent activation of SUMO proteins followed by formation of a thioester bond between a SUMO protein and a conserved active site cysteine residue on UBA2/SAE2