Mutations in the extra sex combs and Enhancer of Polycomb Genes Increase Homologous Recombination in Somatic Cells of Drosophila melanogaster

We found that heterozygous mutant alleles of E(Pc) and esc increased homologous recombination from an allelic template in somatic cells in a P-element-induced double-strand break repair assay. Flies heterozygous for mutant alleles of these genes showed increased genome stability and decreased levels of apoptosis in imaginal discs and a concomitant increase in survival following ionizing radiation. We propose that this was caused by a genomewide increase in homologous recombination in somatic cells. A double mutant of E(Pc) and esc had no additive effect, showing that these genes act in the same pathway. Finally, we found that a heterozygous deficiency for the histone deacetylase, Rpd3, masked the radiation-resistant phenotype of both esc and E(Pc) mutants. These findings provide evidence for a gene dosage-dependent interaction between the esc/E(z) complex and the Tip60 histone acetyltransferase complex. We propose that esc and E(Pc) mutants enhance homologous recombination by modulating the histone acetylation status of histone H4 at the double-strand break.

[1]  A. Birve,et al.  A 1-Megadalton ESC/E(Z) Complex from Drosophila That Contains Polycomblike and RPD3 , 2003, Molecular and Cellular Biology.

[2]  M. Lohuizen,et al.  Bmi1 is essential for cerebellar development and is overexpressed in human medulloblastomas , 2004, Nature.

[3]  J. Sekelsky,et al.  mus304 encodes a novel DNA damage checkpoint protein required during Drosophila development. , 2000, Genes & development.

[4]  W. Engels,et al.  P-element-induced interallelic gene conversion of insertions and deletions in Drosophila melanogaster , 1993, Molecular and cellular biology.

[5]  John R Yates,et al.  Acetylation by Tip60 Is Required for Selective Histone Variant Exchange at DNA Lesions , 2004, Science.

[6]  Juan F. García,et al.  Abnormal PcG protein expression in Hodgkin's lymphoma. Relation with E2F6 and NFκB transcription factors , 2004, The Journal of pathology.

[7]  G. Gloor,et al.  The effect of heterologous insertions on gene conversion in mitotically dividing cells in Drosophila melanogaster. , 2002, Genetics.

[8]  Victor G Corces,et al.  Polycomb and Trithorax Group Proteins Mediate the Function of a Chromatin Insulator , 1998, Cell.

[9]  Kristian Helin,et al.  Suz12 is essential for mouse development and for EZH2 histone methyltransferase activity , 2004, The EMBO journal.

[10]  S. Kron,et al.  Yng2p-dependent NuA4 Histone H4 Acetylation Activity Is Required for Mitotic and Meiotic Progression* , 2001, The Journal of Biological Chemistry.

[11]  Thomas Helleday,et al.  Conservative homologous recombination preferentially repairs DNA double-strand breaks in the S phase of the cell cycle in human cells. , 2004, Nucleic acids research.

[12]  M. Noll,et al.  The Polycomb‐group gene, extra sex combs, encodes a nuclear member of the WD‐40 repeat family. , 1995, The EMBO journal.

[13]  Jacques Côté,et al.  The highly conserved and multifunctional NuA4 HAT complex. , 2004, Current opinion in genetics & development.

[14]  P. V. van Diest,et al.  Poorly differentiated breast carcinoma is associated with increased expression of the human polycomb group EZH2 gene. , 2003, Neoplasia.

[15]  W. Engels,et al.  The Drosophila Mre11/Rad50 Complex Is Required to Prevent Both Telomeric Fusion and Chromosome Breakage , 2004, Current Biology.

[16]  K. Helin,et al.  Polycomb Group Proteins in Cell Cycle Progression and Cancer , 2004, Cell cycle.

[17]  G. Kroemer,et al.  Apoptosis and genomic instability , 2004, Nature Reviews Molecular Cell Biology.

[18]  D. Lankenau,et al.  The Su(Hw) chromatin insulator protein alters double-strand break repair frequencies in the Drosophila germ line , 2000, Chromosoma.

[19]  G. Robertson,et al.  A novel human homologue of Drosophila polycomblike gene is up-regulated in multiple cancers. , 2004, Gene.

[20]  W. Engels,et al.  A stable genomic source of P element transposase in Drosophila melanogaster. , 1988, Genetics.

[21]  Song Tan,et al.  Structural and Functional Conservation of the NuA4 Histone Acetyltransferase Complex from Yeast to Humans , 2004, Molecular and Cellular Biology.

[22]  J. Tyler,et al.  Localized Histone Acetylation and Deacetylation Triggered by the Homologous Recombination Pathway of Double-Strand DNA Repair , 2005, Molecular and Cellular Biology.

[23]  Song Tan,et al.  Yeast enhancer of polycomb defines global Esa1-dependent acetylation of chromatin. , 2003, Genes & development.

[24]  T. Furuyama,et al.  Polycomb group proteins ESC and E(Z) are present in multiple distinct complexes that undergo dynamic changes during development , 2003, Genesis.

[25]  F. Alt,et al.  Collaboration of homologous recombination and nonhomologous end-joining factors for the survival and integrity of mice and cells. , 2004, Genes & development.

[26]  G. Peters,et al.  Role of polycomb group proteins in stem cell self-renewal and cancer. , 2005, DNA and cell biology.

[27]  V. Corces,et al.  A chromatin insulator determines the nuclear localization of DNA. , 2000, Molecular cell.

[28]  R. Kingston,et al.  Reconstitution of a functional core polycomb repressive complex. , 2001, Molecular cell.

[29]  Ali Jazayeri,et al.  Saccharomyces cerevisiae Sin3p facilitates DNA double-strand break repair. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[30]  D. Lindsley,et al.  The Genome of Drosophila Melanogaster , 1992 .

[31]  Nicola J. Rinaldi,et al.  Global position and recruitment of HATs and HDACs in the yeast genome. , 2004, Molecular cell.

[32]  W. Engels,et al.  High-frequency P element loss in Drosophila is homolog dependent , 1990, Cell.

[33]  N. Nassif,et al.  Targeted gene replacement in Drosophila via P element-induced gap repair , 1991, Science.

[34]  J. Haber.  Partners and pathwaysrepairing a double-strand break. , 2000, Trends in genetics : TIG.

[35]  D. Reinberg,et al.  Composition and histone substrates of polycomb repressive group complexes change during cellular differentiation. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[36]  Kristian Helin,et al.  EZH2 is downstream of the pRB‐E2F pathway, essential for proliferation and amplified in cancer , 2003, The EMBO journal.

[37]  E. Hendrickson,et al.  Cell-cycle regulation of mammalian DNA double-strand-break repair. , 1997, American journal of human genetics.

[38]  P. Farnham,et al.  Identification of the polycomb group protein SU(Z)12 as a potential molecular target for human cancer therapy. , 2003, Molecular cancer therapeutics.

[39]  C. Sardet,et al.  A Novel Repressive E2F6 Complex Containing the Polycomb Group Protein, EPC1, That Interacts with EZH2 in a Proliferation-specific Manner* , 2005, Journal of Biological Chemistry.

[40]  E. Bilsland,et al.  Tails of histones in DNA double-strand break repair. , 2005, Mutagenesis.

[41]  S. Kron,et al.  NuA4 Subunit Yng2 Function in Intra-S-Phase DNA Damage Response , 2002, Molecular and Cellular Biology.

[42]  J. Masson,et al.  Chromatin remodeling and the maintenance of genome integrity. , 2004, Biochimica et biophysica acta.

[43]  Alexander W. Bird,et al.  Acetylation of histone H4 by Esa1 is required for DNA double-strand break repair , 2002, Nature.

[44]  C. Meijer,et al.  Unique polycomb gene expression pattern in Hodgkin's lymphoma and Hodgkin's lymphoma-derived cell lines. , 2004, The American journal of pathology.

[45]  C. Desmaze,et al.  Impact of the KU80 pathway on NHEJ-induced genome rearrangements in mammalian cells. , 2004, Molecular cell.

[46]  G. Gloor,et al.  Distinct P-element excision products in somatic and germline cells of Drosophila melanogaster. , 2000, Genetics.

[47]  V. Corces,et al.  Visualization of chromatin domains created by the gypsy insulator of Drosophila , 2003, The Journal of cell biology.