HMGB1-mediated DNA bending: Distinct roles in increasing p53 binding to DNA and the transactivation of p53-responsive gene promoters

0492523 - BFÚ 2019 RIV NL eng J - Článek v odborném periodiku
Štros, Michal - Kučírek, Martin - Sani, Soodabeh Abbasi - Polanská, Eva
HMGB1-mediated DNA bending: Distinct roles in increasing p53 binding to DNA and the transactivation of p53-responsive gene promoters.
Biochimica et Biophysica Acta-Gene Regulatory Mechanisms. Roč. 1861, č. 3 (2018), s. 200-210. ISSN 1874-9399. E-ISSN 1876-4320
Grant CEP: GA ČR GA15-01354S
Institucionální podpora: RVO:68081707
Klíčová slova: hmg-box domains * chromosomal-protein hmg1 * mobility group-1 protein * cisplatin-modified dna
Obor OECD: Biochemistry and molecular biology
Impakt faktor: 4.599, rok: 2018

HMGB1 is a chromatin-associated protein that has been implicated in many important biological processes such as transcription, recombination, DNA repair, and genome stability. These functions include the enhancement of binding of a number of transcription factors, including the tumor suppressor protein p53, to their specific DNA binding sites. HMGB1 is composed of two highly conserved HMG boxes, linked to an intrinsically disordered acidic C-terminal tail. Previous reports have suggested that the ability of HMGB1 to bend DNA may explain the in vitro HMGB1-mediated increase in sequence-specific DNA binding by p53. The aim of this study was to reinvestigate the importance of HMGB1-induced DNA bending in relationship to the ability of the protein to promote the specific binding of p53 to short DNA duplexes in vitro, and to transactivate two major p53-regulated human genes: Mdm2 and p21/WAF1. Using a number of HMGB1 mutants, we report that the HMGB1-mediated increase in sequence-specific p53 binding to DNA duplexes in vitro depends very little on HMGB1-mediated DNA bending. The presence of the acidic C-terminal tail of HMGB1 and/or the oxidation of the protein can reduce the HMGB1-mediated p53 binding. Interestingly, the induction of transactivation of p53-responsive gene promoters by HMGB1 requires both the ability of the protein to bend DNA and the acidic C-terminal tail, and is promoter specific. We propose that the efficient transactivation of p53-responsive gene promoters by HMGB1 depends on complex events, rather than solely on the promotion of p53 binding to its DNA cognate sites.
Trvalý link: http://hdl.handle.net/11104/0286023