| First Author | Okano M | Year | 1998 |
| Journal | Nucleic Acids Res | Volume | 26 |
| Issue | 11 | Pages | 2536-40 |
| PubMed ID | 9592134 | Mgi Jnum | J:48082 |
| Mgi Id | MGI:1261708 | Doi | 10.1093/nar/26.11.2536 |
| Citation | Okano M, et al. (1998) Dnmt2 is not required for de novo and maintenance methylation of viral DNA in embryonic stem cells. Nucleic Acids Res 26(11):2536-40 |
| abstractText | We have shown previously that de novo methylation activities persist in mouse embryonic stem (ES) cells homozygous for a null mutation of Dnmt1 that encodes the major DNA cytosine methyltransferase. In this study, we have cloned a putative mammalian DNA methyltransferase gene, termed Dnmt2 , that is homologous to pmt1 of fission yeast. Different from pmt1 in which the catalytic Pro-Pro-Cys (PPC) motif is 'mutated' to Pro-Ser-Cys, Dnmt2 contains all the conserved methyltransferase motifs, thus likely encoding a functional cytosine methyltransferase. However, baculovirus-expressed Dnmt2 protein failed to methylate DNA in vitro . To investigate whether Dnmt2 functions as a DNA methyltransferase in vivo , we inactivated the Dnmt2 gene by targeted deletion of the putative catalytic PPC motif in ES cells. We showed that endogenous virus was fully methylated in Dnmt2 -deficient mutant ES cells. Furthermore, newly integrated retrovirus DNA was methylated de novo in infected mutant ES cells as efficiently as in wild-type cells. These results indicate that Dnmt2 is not essential for global de novo or maintenance methylation of DNA in ES cells. |
