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N ⁶-methyladenosine binding induces a metal-centered rearrangement that activates the human RNA demethylase Alkbh5.

ABSTRACT: Alkbh5 catalyzes demethylation of the N ⁶-methyladenosine (m⁶A), an epigenetic mark that controls several physiological processes including carcinogenesis and stem cell differentiation. The activity of Alkbh5 comprises two coupled reactions. The first reaction involves decarboxylation of α-ketoglutarate (αKG) and formation of a Fe⁴⁺═O species. This oxyferryl intermediate oxidizes the m⁶A to reestablish the canonical base. Despite coupling between the two reactions being required for the correct Alkbh5 functioning, the mechanisms linking dioxygen activation to m⁶A binding are not fully understood. Here, we use solution NMR to investigate the structure and dynamics of apo and holo Alkbh5. We show that binding of m⁶A to Alkbh5 induces a metal-centered rearrangement of αKG that increases the exposed area of the metal, making it available for binding O₂ Our study reveals the molecular mechanisms underlying activation of Alkbh5, therefore opening new perspectives for the design of novel strategies to control gene expression and cancer progression.

SUBMITTER: Purslow JA

PROVIDER: S-EPMC8373141 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Promoting axon regeneration by inhibiting RNA N6-methyladenosine demethylase ALKBH5.

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The N6-methyladenosine demethylase ALKBH5 regulates the hypoxic HBV transcriptome.

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