Preimplantation embryos

Coberly S, Oudiz DJ, Overstreet JW, et al. 1992. Effects of maternal exposure to trichloroethylene (TCE) on cell proliferation in the mouse preimplantation embryo. Reprod Toxicol 6 241-245. 

Paria BC, Das SK, Dey SK. The preimplantation embryo is a target for cannabinoid ligand-receptor signaling. Proc Natl Acad Sci USA 1996 92 9430-9464. 

Adjaye J et al. cDNA libraries from single human preimplantation embryos. Genomics 1997 46 337-344. 

Barr, Dana B., et al. (2004). Concentrations of dialkyl phosphate metabolites of organophosphorus pesticides in the U.S. population. Environmental Health Perspectives 112(2) 186-200. Greenlee, A. R., T. M. Ellis, and R. L. Berg. (2004). Low-dose agrochemicals and lawn-care pesticides induce developmental toxicity in murine preimplantation embryos. Environmental Health Perspectives 112(6) 703-709. 

Costanzi, C., Stein, P., Worrad, D.M., Schultz, R.M., and Pehrson, J.R. (2000) Histone macroH2Al is concentrated in the inactive X chromosome of female preimplantation embryos. Development 127, 2283-2289. 

The methylation of DNA at CpG islands has also turned out to be an important regulator for cell development, the differentiated proteome and the regulation of cell survival [237,238]. Indeed the implications of this chemical modification have been linked to DNA accessibility, chromatin fluidity and cell transformation [239,240]. DNA methylation is required for genomic stability and believed to act as an inert epigenetic marker in germinal cells and preimplantation embryos [238]. Presumably, DNA methylation is required for the heritable transmission of chromatin structure, which prevents the expression of terminally silenced genes in differentiated tissues, and provides a host-defense mechanism against parasitic transposable elements [241]. 

Duncan EE and Schultz RM (2010) Gene expression profiling of mouse oocytes and preimplantation embryos. Methods Enzymol 477 457-480. 

Treatment starts when the embryo is attached to the uterine wall and has completed the first stages of implantation. Therefore, pre-implantation development should be unaffected by the test substance. However, even in controls, not all fertilized oocytes develop to the hatched blastocyst stage. A loss of up to two preimplantation embryos per female can be considered a normal finding in rats and rabbits. In studies where exposure begins at or before fertilization a dose-dependent increase in the number of females that show larger differences between corpora lutea and implantation sites may indicate toxicity to pre-implantation embryos or the process of implantation itself. 

Lindenau A Fischer (1996) Embryotoxicity of polychlorinated biphenyls (PCBs) for preimplantation embryos. Reprod Toxicol, 10 227-230. 

In a study of the Qa-2-expression regulation by the transporter associated with antigen processing (TAP) protein, Ke and Warner [14] reported the monitoring of preimplantation embryos from TAP-1 knockout and normal mice by IPCR and RT-PCR. IPCR was carried out as described by McElhinny et al. [17]. Again, IPCR proved its potential as a valuable tool for the analysis of protein expression on the cell surface from small numbers (2-20) of one-cell and two-cell embryos, as well as blastocystes. 

McElhinny AS, Exley GE, Warner CM. Painting Qa-2 onto Ped slow preimplantation embryos increases the rate of cleavage. Am J Reprod Immunol 2000 44(1) 52—58. 

McElhinny AS, Kadow N, Warner CM. The expression pattern of the Qa-2 antigen in mouse preimplantation embryos and its correlation with the Ped gene phenotype. Mol Hum Reprod 1998 4(10) 966-971. 

Blankenship AL, Suffia MC, Matsumura F, et al. 1993. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCCD) accelerated differentiation of murine preimplantation embryos in vitro. Reprod Toxicol 7(3) 255-261. 

Paria, B. C., and Dey, S. K. (2000). Ligand-receptor signaling with endocannabinoids in preimplantation embryo development and implantation. Chem. Phys. Lipids 108, 211-220. 

Spielmann H, Eibs H, Jacob-Mueller U. 1980. In vitro methods for the study of the effects of teratogens on preimplantation embryos. Acta Morphol Acad Sci Hung 28 105-115. 

Some of the major features of the two IFN families are summarized in Table 1. The IFNa// or type I IFN superfamily is further subdivided into subfamilies termed IFNa, IFN/ , and IFNw. A distinct trophoblast IFN (IFNr) subfamily has been identified in cattle and sheep (Imakawa et al., 1987). IFNr is produced in the epithelium of the early preimplantation embryo and has been implicated as a factor responsible for the preservation of the corpus luteum, essential for successful completion of the pregnancy. 

Eggens 1, Fenderson B, Toyokuni T, Dean B, Stroud M, Elakomori 35. S. Specific interaction between Le-x and Le-x determinants. A possible basis for cell recognition in preimplantation embryos and in embryonal carcinoma cells. J. Biol. Chem. 1989 264 9476-9484. 

Peters JM, Wiley LM. 1995. Evidence that murine preimplantation embryos express aryl hydrocarbon receptor. Toxicol. Appl. Pharmacol. 134 214-21... 

Greenlee AR, Ellis TM, Berg RL. Low-dose agrochemicals and lawn-care pesticides induce developmental toxicity in murine preimplantation embryos. Environ Health Perspect 2004 112 (6) 703 9. 

The mouse preimplantation assay (MEPA) uses zygotes recovered from mated females, cultured in vitro for 7-10 days to assess embryo development, hatching, and survival that represent the toxicological endpoints [19]. The test is capable to assess toxic effects on preimplantation embryo development and survival in vitro up to hatching, a stage that precedes in vivo embryo implantation. It is a commercially available test, but still it has not been standardized and transferability to other laboratories must be addressed. 

THE REGULATION AND REPROGRAMMING OF GENE EXPRESSION IN THE PREIMPLANTATION EMBRYO... 

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