| First Author | Johnson M | Year | 2009 |
| Journal | Reprod Biomed Online | Volume | 19 |
| Issue | 1 | Pages | 79-88 |
| PubMed ID | 19573295 | Mgi Jnum | J:162183 |
| Mgi Id | MGI:4818303 | Doi | 10.1016/s1472-6483(10)60050-8 |
| Citation | Johnson M, et al. (2009) Maternal enzyme masks the phenotype of mouse embryos lacking dihydrolipoamide dehydrogenase. Reprod Biomed Online 19(1):79-88 |
| abstractText | During early embryogenesis, the phenotype reflecting the embryonic genotype emerges only as maternal proteins are replaced by embryonically encoded forms, a process known as the maternal-to-embryonic transition (MET). Little is understood about MET for most proteins. This study investigates how complete deficiency of the murine dihydrolipoamide dehydrogenase gene (Dld), a gene that encodes an enzyme of mitochondrial energy metabolism, affects the phenotype of the early embryo and how the MET of the DLD protein affects the phenotype. Dld-deficient (-/-) embryos were found to develop similarly to wild-type (+/+) or heterozygous (+/-) embryos throughout the preimplantation period. These three genotypic classes also have comparable rates of glucose uptake (4.9-5.0 pmoles/embryo/h) and lactate production (0.97-1.0 pmoles/embryo/h). Dld-deficient embryos at the end of the preimplantation stage have 44% of DLD enzyme present in oocytes, a proportion similar to that found in +/+ or +/- embryos. This study demonstrates that Dld-deficient preimplantation embryos are phenotypically normal, as the MET for the DLD enzyme is only partially complete by the end of the preimplantation period. These findings have implications for phenotype- or enzyme-based approaches to identify mutations in Dld and other genes that encode proteins with similar MET kinetic profiles. |
