Non-histone chromosomal proteins HMG1 and 2 enhance ligation reaction of DNA double-strand breaks.
DNA ligase IV in a complex with XRCC4 is responsible for DNA end-joining in repair of DNA double-strand breaks (DSB) and V(D)J recombination. We found that non-histone chromosomal high mobility group (HMG) proteins 1 and 2 enhanced the ligation of linearized pUC119 DNA with DNA ligase IV from rat liver nuclear extract. Intra-molecular and inter-molecular ligations of cohesive-ended and blunt-ended DNA were markedly stimulated by HMG1 and 2. Recombinant HMG2-domain A, B, and (A + B) polypeptides were similarly, but non-identically, effective for the stimulation of DSB ligation reaction. Ligation of single-strand breaks (nicks) was only slightly activated by the HMG proteins. The DNA end-binding Ku protein singly or in combination with the catalytic component of DNA-dependent protein kinase (DNA-PK) as the DNA-PK holoenzyme was ineffective for the ligation of linearized pUC119 DNA. Although the stimulatory effect of HMG1 and 2 on ligation of DSB in vitro was not specific to DNA ligase IV, these results suggest that HMG1 and 2 are involved in the final ligation step in DNA end-joining processes of DSB repair and V(D)J recombination.
Nagaki
S
S
Department of Pathological Biochemistry, Tokyo Medical and Dental University, Japan.
Yamamoto
M
M
Yumoto
Y
Y
Shirakawa
H
H
Yoshida
M
M
Teraoka
H
H
D000818:Animals; D034961:Antigens, Nuclear; D002467:Cell Nucleus / Q000378:metabolism; D004249:DNA Damage; D004265:DNA Helicases; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000302:isolation & purification / Q000378:metabolism; D004260:DNA Repair / Q000187:drug effects* / Q000502:physiology*; D004277:DNA, Single-Stranded / Q000378:metabolism; D051747:DNA-Activated Protein Kinase; D004268:DNA-Binding Proteins / Q000378:metabolism / Q000494:pharmacology; D006609:High Mobility Group Proteins / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D000072200:Ku Autoantigen; D008099:Liver / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D013552:Swine
D034961:Antigens, Nuclear; D004277:DNA, Single-Stranded; D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; C000607893:LIG4 protein, human; C000607895:Lig1 protein, rat; D009687:Nuclear Proteins; D011994:Recombinant Proteins; D051747:DNA-Activated Protein Kinase; C497263:PRKDC protein, human; D017346:Protein Serine-Threonine Kinases; D004265:DNA Helicases; C106893:XRCC5 protein, human; C000606509:Xrcc6 protein, human; C000606511:Xrcc6 protein, rat; D000072200:Ku Autoantigen; D011088:DNA Ligases; D000072481:DNA Ligase ATP