Dietary and metabolic compounds affecting covalent histone modifications

Libro: Handbook of epigenetics: the new molecular and medical genetics
Autores: Milagro Yoldi, Fermín Ignacio; Martínez Hernández, Alfredo
Editorial: Academic Press 
ISBN: 978-0-12-805388-1
Página inicial-final: 307 - 322
Fecha de publicación: 2017
Resumen: This chapter focuses on the effect of metabolic and dietary compounds, as well as the metabolic state, on relevant post-translational histone modifications, with emphasis on acetylation and methylation of histones H3 and H4. The fundamental unit of the chromatin is the nucleosome, which consists of approximately 147 base pairs of DNA wrapped around a histone octamer containing two copies of each of the four conserved core histones¿H2A, H2B, H3, and H4. Chromatin is further compacted by the incorporation of the linker histone H1, which has been reported to have eight isoforms in higher eukaryotes. There are also variant histone subspecies that are recognized by differences in their amino acid sequence relative to the major histone species. Each protein has both a histone fold domain, which mediates the histone¿histone and histone¿DNA interactions that are crucial for the assembly of the nucleosome core particle, and a flexible amino-terminal tail domain, which protrudes from the nucleosome core particle. There are various histone post-transcriptional modifications that decorate the canonical histones (H2A, H2B, H3, and H4), as well as variant histones (such as H3.1, H3.3, and HTZ.1). The combination of modifications (¿marks¿) produced by specific enzymes has been proposed to constitute a code that regulates downstream processes such as gene transcription, DNA repair, and apoptosis.