Metastases suppressor NM23-H2 interaction with G-quadruplex DNA within c-MYC promoter nuclease hypersensitive element...

Area of Science:

• Molecular Biology
• Gene Regulation
• Biochemistry

Background:

• The c-MYC gene promoter contains a nuclease hypersensitive element (NHE) with a G-quadruplex (G4) motif, known to influence gene regulation.
• The protein NM23-H2 has been associated with the activation of c-MYC.

Purpose of the Study:

• To investigate the mechanistic link between NM23-H2 and the G4 motif within the c-MYC NHE.
• To determine if NM23-H2 directly interacts with the G4 motif and if this binding is responsible for c-MYC activation.

Main Methods:

• Luciferase reporter assays were employed to assess c-MYC promoter activity.
• Chromatin immunoprecipitation (ChIP) was used to detect NM23-H2 binding to the c-MYC NHE.
• Fluorescence energy transfer (FRET) assays were utilized to confirm direct binding between NM23-H2 and the G4 motif.

Main Results:

• NM23-H2 mediated c-MYC activation was shown to involve direct binding to the G4 motif within the c-MYC NHE.
• ChIP assays confirmed the association of NM23-H2 with the c-MYC NHE.
• FRET analysis confirmed complex formation between recombinant NM23-H2 and the G4 motif, demonstrating G4 motif resolution upon binding.

Conclusions:

• NM23-H2 directly binds to the G4 motif in the c-MYC NHE, leading to c-MYC transcriptional activation.
• This study elucidates a novel mechanism for transcriptional regulation involving direct protein-G4 motif interaction.