Histone PARylation factor 1
1_MVGGG 6_ GKRRP 11_ GGEGP 16_ QCEKT 21_ TDVKK 26_ SKFCE 31_ ADVSS 36_ DLRKE 41_ VENHY 46_ KLSLP 51_ EDFYH 56_ FWKFC 61_ EELDP 66_ EKPSD 71_ SLSAS 76_ LGLQL 81_ VGPYD 86_ ILAGK 91_ HKTKK 96_ KSTGL 101_ NFNLH 106_ WRFYY 111_ DPPEF 116_ QTIII 121_ GDNKT 126_ QYHMG 131_ YFRDS 136_ PDEFP 141_ VYVGI 146_ NEAKK 151_ NCIIV 156_ PNGDN 161_ VFAAV 166_ KLFLT 171_ KKLRE 176_ ITDKK 181_ KINLL 186_ KNIDE 191_ KLTEA 196_ ARELG 201_ YSLEQ 206_ RTVKM 211_ KQRDK 216_ KVVTK 221_ TFHGA 226_ GLVVP 231_ VDKND 236_ VGYRE 241_ LPETD 246_ ADLKR 251_ ICKTI 256_ VEAAS 261_ DEERL 266_ KAFAP 271_ IQEMM 276_ TFVQF 281_ ANDEC 286_ DYGMG 291_ LELGM 296_ DLFCY 301_ GSHYF 306_ HKVAG 311_ QLLPL 316_ AYNLL 321_ KRNLF 326_ AEIIE 331_ EHLAN 336_ RSQEN 341_IDQLA
1: Cofactor for serine ADP-ribosylation that confers serine specificity on PARP1 and PARP2 and plays a key role in DNA damage response (PubMed:28190768, PubMed:29480802, PubMed:29954836, PubMed:32028527, PubMed:32939087, PubMed:33186521, PubMed:33589610, PubMed:33683197, PubMed:34108479, PubMed:34210965, PubMed:34486521, PubMed:34625544, PubMed:34732825, PubMed:34795260, PubMed:34874266). Initiates the repair of double-strand DNA breaks: recruited to DNA damage sites by PARP1 and PARP2 and switches the amino acid specificity of PARP1 and PARP2 from aspartate or glutamate to serine residues, licensing serine ADP-ribosylation of target proteins (PubMed:28190768, PubMed:29480802, PubMed:29954836, PubMed:32028527, PubMed:32939087, PubMed:33589610, PubMed:33683197, PubMed:34486521, PubMed:34625544, PubMed:34732825, PubMed:34795260, PubMed:34874266). Serine ADP-ribosylation of target proteins, such as histones, promotes decompaction of chromatin and the recruitment of repair factors leading to the reparation of DNA strand breaks (PubMed:27067600, PubMed:28190768, PubMed:32939087, PubMed:33589610). Serine ADP-ribosylation of proteins constitutes the primary form of ADP-ribosylation of proteins in response to DNA damage (PubMed:29480802). HPF1 acts by completing the active site of PARP1 and PARP2: forms a composite active site composed of residues from HPF1 and PARP1 or PARP2 (PubMed:32028527, PubMed:33589610). While HPF1 promotes the initiation of serine ADP-ribosylation, it restricts the polymerase activity of PARP1 and PARP2 in order to limit the length of poly-ADP-ribose chains (PubMed:33683197, PubMed:34732825, PubMed:34795260). HPF1 also promotes tyrosine ADP-ribosylation, probably by conferring tyrosine specificity on PARP1 (PubMed:29954836, PubMed:30257210)