RESUMO
In the mouse, ZFP57 contains three classical Cys2His2 zinc finger domains (ZF) and recognizes the methylated TGC(met)CGC target sequence using the first and the second ZFs. In this study, we demonstrate that the human ZFP57 (hZFP57) containing six Cys2His2 ZFs, binds the same methylated sequence through the third and the fourth ZFs, and identify the aminoacids critical for DNA interaction. In addition, we present evidences indicating that hZFP57 mutations and hypomethylation of the TNDM1 ICR both associated with Transient Neonatal Diabetes Mellitus type 1 result in loss of hZFP57 binding to the TNDM1 locus, likely causing PLAGL1 activation.
Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Diabetes Mellitus/genética , Epigênese Genética/fisiologia , Doenças do Recém-Nascido/genética , Mutação/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Metilação de DNA/genética , Diabetes Mellitus/metabolismo , Células-Tronco Embrionárias/metabolismo , Epigênese Genética/genética , Humanos , Recém-Nascido , Doenças do Recém-Nascido/metabolismo , Camundongos , Dados de Sequência Molecular , Ligação Proteica/genética , Proteínas Repressoras , Homologia de Sequência de Aminoácidos , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismoRESUMO
Several oxime containing molecules, characterized by a SAHA-like structure, were explored to select a potentially new biasing binding element for the zinc in HDAC catalytic site. All compounds were evaluated for their in vitro inhibitory activity against the 11 human HDACs isoforms. After identification of a "hit" molecule, a programmed variation at the cap group and at the linker was carried out in order to increase HDAC inhibition and/or paralogue selectivity. Some of the new derivatives showed increased activity against a number of HDAC isoforms, even if their overall activity range is still far from the inhibition values reported for SAHA. Moreover, different from what was reported for their hydroxamic acid analogues the new α-oxime amide derivatives do not select between class I and class II HDACs; rather they target specific isoforms in each class. These somehow contradictory results were finally rationalized by a computational assisted SAR, which gave us the chance to understand how the oxime derivatives interact with the catalytic site and justify the observed activity profile.
