Structural insights into the role of domain flexibility in human DNA ligase IV.
Knowledge of the architecture of DNA ligase IV (LigIV) and interactions with XRCC4 and XLF-Cernunnos is necessary for understanding its role in the ligation of double-strand breaks during nonhomologous end joining. Here we report the structure of a subdomain of the nucleotidyltrasferase domain of human LigIV and provide insights into the residues associated with LIG4 syndrome. We use this structural information together with the known structures of the BRCT/XRCC4 complex and those of LigIV orthologs to interpret small-angle X-ray scattering of LigIV in complex with XRCC4 and size exclusion chromatography of LigIV, XRCC4, and XLF-Cernunnos. Our results suggest that the flexibility of the catalytic region is limited in a manner that affects the formation of the LigIV/XRCC4/XLF-Cernunnos complex.
Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA, UK. to237@cam.ac.uk
Takashi
T
Ochi
Qian
Q
Wu
Dimitri Y
DY
Chirgadze
J Günter
JG
Grossmann
Victor M
VM
Bolanos-Garcia
Tom L
TL
Blundell
D020134:Catalytic Domain; D002850:Chromatography, Gel; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D053903:DNA Breaks, Double-Stranded; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004254:DNA Nucleotidyltransferases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004260:DNA Repair; D045643:DNA Repair Enzymes / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli; D006801:Humans; D008958:Models, Molecular; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D053838:Scattering, Small Angle; D014961:X-Ray Diffraction
D004268:DNA-Binding Proteins; C000607893:LIG4 protein, human; C508551:NHEJ1 protein, human; D011994:Recombinant Proteins; C101467:XRCC4 protein, human; D004247:DNA; D004254:DNA Nucleotidyltransferases; D011088:DNA Ligases; D045643:DNA Repair Enzymes; D000072481:DNA Ligase ATP