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Surprising Phenotypic Diversity of Cancer-associated mutations at Gly 34 in the Histone H3 tail

ABSTRACT: Deep sequencing of cancer genomes has identified frequent mutation of core histones, termed oncohistones, but the role of some mutants is poorly understood. Here, using fission yeast as a model, we determine the consequences of mutation of histone H3.3 at Gly 34, a site frequently mutated in pediatric cortical high-grade glioma (G34R/V), and in virtually all giant cell tumors of bone (G34W). H3-G34 mutations cause a surprising diversity of outcomes, differentially affecting modification of the nearby H3K36 residue, subtelomeric silencing, genomic stability, sensitivity to irradiation, alkylating agents, hydroxyurea and influencing DNA repair. Since fifteen genes encode H3 isoforms, and only one allele is targeted in cancer, G34R/V/W H3 likely represents a small portion of total cellular H3. Whilst the presence of wild type H3 rescues most G34 mutant phenotypes, hydroxyurea sensitivity, subtelomeric silencing and homologous recombination defects dominate in cells expressing G34R and wild type H3. Together, these studies demonstrate the complexity associated with different substitutions at even a single residue in histone H3 and highlight the utility of genetically tractable systems for their analysis.

ORGANISM(S): Schizosaccharomyces pombe

PROVIDER: GSE162572 | GEO | 2021/02/08

REPOSITORIES: GEO

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| PRJNA682226 | ENA