title: DNA-HMGB1 interaction: The nuclear aggregates of polyamine mediation.
abstract: Nuclear aggregates of polyamines (NAPs) are supramolecular compounds generated by the self-assembly of protonated nuclear polyamines (spermine, spermidine and putrescine) and phosphate ions. In the presence of genomic DNA, the hierarchical process of self-structuring ultimately produces nanotube-like polymers that envelop the double helix. Because of their modular nature and their aggregation-disaggregation dynamics, NAPs confer plasticity and flexibility to DNA. Through the disposition of charges, NAPs also enable a bidirectional stream of information between the genome and interacting moieties. High mobility group (HMG) B1 is a non-histone chromosomal protein that binds to DNA and that influences multiple nuclear processes. Because genomic DNA binds to either NAPs or HMGB1 protein, we explored the ability of in vitro self-assembled NAPs (ivNAPs) to mediate the DNA-HMGB1 interaction. To this end, we structured DNA-NAPs-HMGB1 and DNA-HMGB1-NAPs ternary complexes in vitro through opportune sequential incubations. Mobility shift electrophoresis and atomic force microscopy showed that the DNA-ivNAPs-HGMB1 complex had conformational assets supposedly more suitable those of the DNA-HGMB1-ivNAPs to comply with the physiological and functional requirements of DNA. Our findings indicated that ivNAPs act as mediators of the DNA-HMGB1 interaction.
authors.affiliation: Istituto di Scienze dell'Alimentazione - CNR, Via Roma 64 - 83100, Avellino, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Iacomino
authors.affiliation: Istituto di Scienze dell'Alimentazione - CNR, Via Roma 64 - 83100, Avellino, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Picariello
authors.affiliation: Istituto di Biofisica - CNR, Via De Marini 6 - 16149, Genova, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Sbrana
authors.affiliation: Istituto di Biofisica - CNR, Via De Marini 6 - 16149, Genova, Italy; Dipartimento di Informatica, Bioingegneria, Robotica ed Ingegneria dei Sistemi - Università degli Studi di Genova, Via All'Opera Pia 13 - 16145, Genova, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Raiteri
authors.affiliation: Istituto di Scienze dell'Alimentazione - CNR, Via Roma 64 - 83100, Avellino, Italy. Electronic address: luciano@isa.cnr.it.
authors.forename: Luciano
authors.initials: L
authors.lastname: D'Agostino
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism*; D004247:DNA / Q000378:metabolism*; D016678:Genome / Q000235:genetics; D024243:HMGB1 Protein / Q000378:metabolism*; D006801:Humans; D018625:Microscopy, Atomic Force / Q000379:methods; D009690:Nucleic Acid Conformation; D011073:Polyamines / Q000378:metabolism*; D066329:Protein Aggregates / Q000502:physiology*; D013095:Spermidine / Q000378:metabolism; D013096:Spermine / Q000378:metabolism
chemical_list: D024243:HMGB1 Protein; D011073:Polyamines; D066329:Protein Aggregates; D013096:Spermine; D004247:DNA; D013095:Spermidine
keywords: Atomic force microscopy; DNA conformational transitions; EMSA; HMGB1; Nuclear aggregates of polyamines; Supramolecular nanotubes