Eme1 is involved in DNA damage processing and maintenance of genomic stability in mammalian cells.
Yeast and human Eme1 protein, in complex with Mus81, constitute an endonuclease that cleaves branched DNA structures, especially those arising during stalled DNA replication. We identified mouse Eme1, and show that it interacts with Mus81 to form a complex that preferentially cleaves 3'-flap structures and replication forks rather than Holliday junctions in vitro. We demonstrate that Eme1-/- embryonic stem (ES) cells are hypersensitive to the DNA cross-linking agents mitomycin C and cisplatin, but only mildly sensitive to ionizing radiation, UV radiation and hydroxyurea treatment. Mammalian Eme1 is not required for the resolution of DNA intermediates that arise during homologous recombination processes such as gene targeting, gene conversion and sister chromatid exchange (SCE). Unlike Blm-deficient ES cells, increased SCE was seen only following induced DNA damage in Eme1-deficient cells. Most importantly, Eme1 deficiency led to spontaneous genomic instability. These results reveal that mammalian Eme1 plays a key role in DNA repair and the maintenance of genome integrity.
Abraham
Jacinth
J
Advanced Medical Discovery Institute, Ontario Cancer Institute, 620 University Avenue, Suite 706, Toronto, Ontario M5G 2C1, Canada.
Lemmers
Bénédicte
B
Hande
M Prakash
MP
Moynahan
Mary Ellen
ME
Chahwan
Charly
C
Ciccia
Alberto
A
Essers
Jeroen
J
Hanada
Katsuhiro
K
Chahwan
Richard
R
Khaw
Aik Kia
AK
McPherson
Peter
P
Shehabeldin
Amro
A
Laister
Rob
R
Arrowsmith
Cheryl
C
Kanaar
Roland
R
West
Stephen C
SC
Jasin
Maria
M
Hakem
Razqallah
R
D000595:Amino Acid Sequence; D000818:Animals; D043171:Chromosomal Instability; D004249:DNA Damage; D004260:DNA Repair / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D004720:Endonucleases / Q000235:genetics / Q000378:metabolism; D042822:Genomic Instability; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics; D012854:Sister Chromatid Exchange; D013234:Stem Cells
D004268:DNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C442837:Eme1 protein, S pombe; C480534:Eme1 protein, mouse; D004706:Endodeoxyribonucleases; D004720:Endonucleases; C411624:MUS81 protein, S cerevisiae; C498772:MUS81 protein, human; C498773:Mus81 protein, mouse