Isolation and characterization of a novel DNA methyltransferase complex linking DNMT3B with components of the mitotic chromosome condensation machinery.
Proper patterns of genome-wide DNA methylation, mediated by DNA methyltransferases DNMT1, -3A and -3B, are essential for embryonic development and genomic stability in mammalian cells. The de novo DNA methyltransferase DNMT3B is of particular interest because it is frequently overexpressed in tumor cells and is mutated in immunodeficiency, centromere instability and facial anomalies (ICF) syndrome. In order to gain a better understanding of DNMT3B, in terms of the targeting of its methylation activity and its role in genome stability, we biochemically purified endogenous DNMT3B from HeLa cells. DNMT3B co-purifies and interacts, both in vivo and in vitro, with several components of the condensin complex (hCAP-C, hCAP-E and hCAP-G) and KIF4A. Condensin mediates genome-wide chromosome condensation at the onset of mitosis and is critical for proper segregation of sister chromatids. KIF4A is proposed to be a motor protein carrying DNA as cargo. DNMT3B also interacts with histone deacetylase 1 (HDAC1), the co-repressor SIN3A and the ATP-dependent chromatin remodeling enzyme hSNF2H. Further more, DNMT3B co-localizes with condensin and KIF4A on condensed chromosomes throughout mitosis. These studies therefore reveal the first direct link between the machineries regulating DNA methylation and mitotic chromosome condensation in mammalian cells.
Geiman
Theresa M
TM
Epigenetic Gene Regulation and Cancer Section, LRBGE/NCI/NIH, Bethesda, MD 20892, USA.
Sankpal
Umesh T
UT
Robertson
Andrea K
AK
Chen
Yue
Y
Mazumdar
Manjari
M
Heale
Jason T
JT
Schmiesing
John A
JA
Kim
Wankee
W
Yokomori
Kyoko
K
Zhao
Yingming
Y
Robertson
Keith D
KD
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D020090:Chromosome Segregation; D002875:Chromosomes / Q000737:chemistry* / Q000378:metabolism*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000302:isolation & purification / Q000378:metabolism*; D019175:DNA Methylation; D004268:DNA-Binding Proteins / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006367:HeLa Cells; D006801:Humans; D007399:Interphase; D016547:Kinesins / Q000378:metabolism; D046911:Macromolecular Substances; D008938:Mitosis; D046912:Multiprotein Complexes; D011233:Precipitin Tests; D011485:Protein Binding; D021381:Protein Transport; D012091:Repetitive Sequences, Nucleic Acid; D014981:Xenopus; D000097584:DNA Methyltransferase 3B
D000251:Adenosine Triphosphatases; D002868:Chromosomal Proteins, Non-Histone; D004247:DNA; D004248:DNA (Cytosine-5-)-Methyltransferases; D004268:DNA-Binding Proteins; D016547:Kinesins; D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D000097584:DNA Methyltransferase 3B; C108312:condensin complexes; C484228:KIF4A protein, human; C484229:KIF4B protein, human; C409462:SMARCA5 protein, human