title: The DNA methyltranferase Dnmt2 participates in RNA processing during cellular stress.
abstract: The strong evolutionary conservation of the DNA methyltransferase, Dnmt2, is at odds with the absence of phenotypic defects in organisms lacking Dnmt2. The cellular processes where Dnmt2 has a role to play also remain largely undiscovered. Here we show that Dnmt2 is a part of RNA processing machinery during cellular stress. In addition to interacting with proteins involved in RNA processing and cellular stress, Dnmt2 exhibits nucleo-cytoplasmic shuttling in response to cellular stress. Normally present in the nucleus, under conditions of stress, Dnmt2 relocalises to the cytoplasmic Stress Granules and RNA processing bodies. Surprisingly, for a DNA methyltransferase, knockout of which showed no phenotypic defects in several species, our results show that transient transfection of Dnmt2 in mammalian cells causes cell lethality. Interestingly, Dnmt2 overexpression altered the expression of several genes involved in viral infection. Taking into consideration its recently identified role in retrotransposon silencing, the role of Dnmt2 in stress granules could represent a primitive cellular defense mechanism against viral infection.
authors.affiliation: Laboratory of Mammalian Genetics, CDFD, Hyderabad, India.
authors.forename: Devi
authors.initials: D
authors.lastname: Thiagarajan
authors.forename: Rachana Roshan
authors.initials: RR
authors.lastname: Dev
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Khosla
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000502:physiology; D000818:Animals; D016923:Cell Death / Q000502:physiology; D002467:Cell Nucleus / Q000201:enzymology* / Q000235:genetics; D003593:Cytoplasm / Q000201:enzymology* / Q000235:genetics; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D020868:Gene Silencing / Q000502:physiology; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D012323:RNA Processing, Post-Transcriptional / Q000502:physiology*; D018626:Retroelements / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology*; D014777:Virus Diseases / Q000235:genetics / Q000378:metabolism
chemical_list: D018626:Retroelements; C491786:Dnmt2 protein, mouse; D004248:DNA (Cytosine-5-)-Methyltransferases; C112218:TRDMT1 protein, human