| First Author | Mertineit C | Year | 1998 |
| Journal | Development | Volume | 125 |
| Issue | 5 | Pages | 889-97 |
| PubMed ID | 9449671 | Mgi Jnum | J:46642 |
| Mgi Id | MGI:1201720 | Doi | 10.1242/dev.125.5.889 |
| Citation | Mertineit C, et al. (1998) Sex-specific exons control DNA methyltransferase in mammalian germ cells. Development 125(5):889-97 |
| abstractText | The spermatozoon and oocyte genomes bear sex-specific methylation patterns that are established during gametogenesis and are required for the allele-specific expression of imprinted genes in somatic tissues. The mRNA for Dnmt1, the predominant maintenance and de novo DNA (cytosine-5)-methyl transferase in mammals, is present at high levels in postmitotic murine germ cells but undergoes alternative splicing of sex-specific 5' exons, which controls the production and localization of enzyme during specific stages of gametogenesis. An oocyte-specific 5' exon is associated with the production of very large amounts of active Dnmt1 protein, which is truncated at the N terminus and sequestered in the cytoplasm during the later stages of oocyte growth, while a spermatocyte-specific 5' exon interferes with translation and prevents production of Dnmt1 during the prolonged crossing-over stage of male meiosis. During the course of postnatal oogenesis, Dnmt1 is present at high levels in nuclei only in growing dictyate oocytes, a stage during which gynogenetic developmental potential is lost and biparental developmental potential is gained. |
