| Autor: |
Rivera-Casas C; a Chromatin Structure and Evolution (Chromevol) Group, Department of Biological Sciences, Florida International University, North Miami, FL 33181, USA., González-Romero R; a Chromatin Structure and Evolution (Chromevol) Group, Department of Biological Sciences, Florida International University, North Miami, FL 33181, USA., Vizoso-Vazquez Á; b Exprela Group, Department of Cellular and Molecular Biology, University of A Coruña, A Coruña E15071, Spain., Cheema MS; c Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada., Cerdán ME; b Exprela Group, Department of Cellular and Molecular Biology, University of A Coruña, A Coruña E15071, Spain., Méndez J; d Xenomar Group, Department of Cellular and Molecular Biology, University of A Coruña, A Coruña E15071, Spain., Ausió J; c Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada., Eirin-Lopez JM; a Chromatin Structure and Evolution (Chromevol) Group, Department of Biological Sciences, Florida International University, North Miami, FL 33181, USA. |
| Abstrakt: |
Histones are the fundamental constituents of the eukaryotic chromatin, facilitating the physical organization of DNA in chromosomes and participating in the regulation of its metabolism. The H2A family displays the largest number of variants among core histones, including the renowned H2A.X, macroH2A, H2A.B (Bbd), and H2A.Z. This latter variant is especially interesting because of its regulatory role and its differentiation into 2 functionally divergent variants (H2A.Z.1 and H2A.Z.2), further specializing the structure and function of vertebrate chromatin. In the present work we describe, for the first time, the presence of a second H2A.Z variant (H2A.Z.2) in the genome of a non-vertebrate animal, the mussel Mytilus. The molecular and evolutionary characterization of mussel H2A.Z.1 and H2A.Z.2 histones is consistent with their functional specialization, supported on sequence divergence at promoter and coding regions as well as on varying gene expression patterns. More precisely, the expression of H2A.Z.2 transcripts in gonadal tissue and its potential upregulation in response to genotoxic stress might be mirroring the specialization of this variant in DNA repair. Overall, the findings presented in this work complement recent reports describing the widespread presence of other histone variants across eukaryotes, supporting an ancestral origin and conserved role for histone variants in chromatin. |
