O-GlcNAcylation of High Mobility Group Box 1 (HMGB1) Alters Its DNA Binding and DNA Damage Processing Activities

We performed a comparative analysis of the effect of high-mobility group box protein 1 (HMGB1) on DNA binding by the DNA-binding domains (DBDs) of the androgen, glucocorticoid, progesterone and mineralocorticoid receptors. The affinity of the DBDs of the different receptors for the tyrosine aminotransferase glucocorticoid response element, a classical high-affinity binding element, was augmented up to 7-fold by HMGB1. We found no major differences in the effects of HMGB1 on DNA binding between the different steroid hormone receptors. In transient transfection assays, however, HMGB1 significantly enhances the activity of the glucocorticoid and progesterone receptors but not the androgen or mineralocorticoid receptor. We also investigated the effect of HMGB1 on the binding of the androgen receptor DBD to a subclass of directly repeated response elements that is recognized exclusively by the androgen receptor and not by the glucocorticoid, progesterone or mineralocorticoid receptor. Surprisingly, a deletion of 26 amino acid residues from the C-terminal extension of the androgen receptor DBD does not influence DNA binding but destroys its sensitivity to HMGB1. Deletion of the corresponding fragment in the DBDs of the glucocorticoid, progesterone and mineralocorticoid receptor destroyed their DNA binding. This 26-residue fragment is therefore essential for the influence of HMGB1 on DNA recognition by all steroid hormone receptors that were tested. However, it is dispensable for DNA binding by the androgen receptor.

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The High Mobility Group Protein 1 Enhances Binding of the Estrogen Receptor DNA Binding Domain to the Estrogen Response Element

Molecular Endocrinology ◽

10.1210/mend.12.5.0111 ◽

1998 ◽

Vol 12 (5) ◽

pp. 664-674 ◽

Cited By ~ 23

Author(s):

Lorene E. Romine ◽

Jennifer R. Wood ◽

LuAnne A. Lamia ◽

Paul Prendergast ◽

Dean P. Edwards ◽

...

Keyword(s):

Estrogen Receptor ◽

Dna Binding ◽

High Mobility ◽

High Mobility Group ◽

Estrogen Response Element ◽

Dna Binding Domain ◽

High Mobility Group Protein ◽

Response Element ◽

Estrogen Response ◽

Group Protein

Abstract We have examined the ability of the high-mobility group protein 1 (HMG1) to alter binding of the estrogen receptor DNA-binding domain (DBD) to the estrogen response element (ERE). HMG1 dramatically enhanced binding of purified, bacterially expressed DBD to the consensus vitellogenin A2 ERE in a dose-dependent manner. The ability of HMG1 to stabilize the DBD-ERE complex resulted in part from a decrease in the dissociation rate of the DBD from the ERE. Antibody supershift experiments demonstrated that HMG1 was also capable of forming a ternary complex with the ERE-bound DBD in the presence of HMG1-specific antibody. HMG1 did not substantially affect DBD-ERE contacts as assessed by methylation interference assays, nor did it alter the ability of the DBD to induce distortion in ERE-containing DNA fragments. Because HMG1 dramatically enhanced estrogen receptor DBD binding to the ERE, and the DBD is the most highly conserved region among the nuclear receptor superfamily members, HMG1 may function to enhance binding of other nuclear receptors to their respective response elements and act in concert with coactivator proteins to regulate expression of hormone-responsive genes.

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