This project is concerned with the regulation of metabolism in preimplantation mouse embryos. The overall objective is to define the mechanism by which the mother can render delayed implanting embryos dormant, maintain them in that condition for several days, and then cause them to resume development. Experiments will be conducted at three different levels in an attempt to define point at which the control processes function. Synthesis of RNA. The relative changes in synthesis of mRNA will be determined as delayed implanting embryos are activated in vivo and in vitro. The patter will be compared with that of rRNA as well as overall RNA synthesis to determine whether an increase in synthesis of mRNA precedes that of the others. Messenger RNA will be isolated by means of chromatography with oligo(dT) cellulose. Puromycin and cyclohexamide will be used to determine whether the increases in RNA require prior synthesis of protein. Interaction of the Inner Cell Mass (ICM) and Trophoblast Cells. It has been generally assumed that the ICM influences cell division in trophoblast cells. The ICM will be removed, or a second one added, to delayed implanting embryos by microsurgery. The embryos will be activated with estradiol-17Beta and the effects of the ICM on DNA synthesis will be determined by autoradiography. In vitro Activation of Delayed Implanting Embryos. Qualitative aspects of RNA synthesis and protein synthesis will be compared as embryos are activated in vivo an in vitro. This will be done in order to determine whether the process in vitro is the same as that in vivo and evaluate its usefulness as an experimental model. The effect of low concentrations of Alpha-amanitin and actinomycin D on the synthesis of specific proteins during activation wil be examined.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Research Project (R01)
Project #
5R01HD017437-05
Application #
3314426
Study Section
Reproductive Biology Study Section (REB)
Project Start
1982-07-01
Project End
1986-12-31
Budget Start
1986-01-01
Budget End
1986-12-31
Support Year
5
Fiscal Year
1986
Total Cost
Indirect Cost
Name
Texas Tech University
Department
Type
Schools of Medicine
DUNS #
609980727
City
Lubbock
State
TX
Country
United States
Zip Code
79430
Klemke, R L; Weitlauf, H M (1993) Comparison of the ontogeny of specific cell surface determinants on normal and delayed implanting mouse embryos. J Reprod Fertil 99:167-72
Weitlauf, H M; Knisley, K A (1992) Changes in surface antigens on preimplantation mouse embryos. Biol Reprod 46:811-6
Weitlauf, H M; Suda-Hartman, M (1988) Changes in secreted uterine proteins associated with embryo implantation in the mouse. J Reprod Fertil 84:539-49
Nieder, G L; Weitlauf, H M; Suda-Hartman, M (1987) Synthesis and secretion of stage-specific proteins by peri-implantation mouse embryos. Biol Reprod 36:687-99
Weitlauf, H M (1987) Implantation associated changes in uterine secreted proteins. Adv Exp Med Biol 230:207-20
Sengupta, J; Given, R L; Carey, J B et al. (1986) Primary culture of mouse endometrium on floating collagen gels: a potential in vitro model for implantation. Ann N Y Acad Sci 476:75-94
Weitlauf, H M (1985) Changes in the rate of translation with reactivation of delayed implanting mouse embryos. J Exp Zool 236:309-12
Giebelhaus, D H; Weitlauf, H M; Schultz, G A (1985) Actin mRNA content in normal and delayed implanting mouse embryos. Dev Biol 107:407-13
Nieder, G L; Weitlauf, H M (1985) Effects of metabolic substrates and ionic environment on in-vitro activation of delayed implanting mouse blastocysts. J Reprod Fertil 73:151-7