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The Dimerization State of the Mammalian High Mobility Group Protein AT-Hook 2 (HMGA2).

ABSTRACT: The mammalian high mobility group protein AT-hook 2 (HMGA2) is a chromosomal architectural transcription factor involved in cell transformation and oncogenesis. It consists of three positively charged "AT-hooks" and a negatively charged C-terminus. Sequence analyses, circular dichroism experiments, and gel-filtration studies showed that HMGA2, in the native state, does not have a defined secondary or tertiary structure. Surprisingly, using combined approaches of 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) chemical cross-linking, analytical ultracentrifugation, fluorescence resonance energy transfer (FRET), and mass spectrometry, we discovered that HMGA2 is capable of self-associating into homodimers in aqueous buffer solution. Our results showed that electrostatic interactions between the positively charged "AT-hooks" and the negatively charged C-terminus greatly contribute to the homodimer formation.

SUBMITTER: Frost L

PROVIDER: S-EPMC4482583 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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The Dimerization State of the Mammalian High Mobility Group Protein AT-Hook 2 (HMGA2).

Frost Lorraine L Baez Maria A M MA Harrilal Christopher C Garabedian Alyssa A Fernandez-Lima Francisco F Leng Fenfei F

PloS one 20150626 6

The mammalian high mobility group protein AT-hook 2 (HMGA2) is a chromosomal architectural transcription factor involved in cell transformation and oncogenesis. It consists of three positively charged "AT-hooks" and a negatively charged C-terminus. Sequence analyses, circular dichroism experiments, and gel-filtration studies showed that HMGA2, in the native state, does not have a defined secondary or tertiary structure. Surprisingly, using combined approaches of 1-Ethyl-3-(3-dimethylaminopropyl) ...[more]

PMID: 26114780

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