Embryo, mouse

Desmoplakin is the most abundant desmosomal component that plays a critical role in linking intermediate filament networks to the desmosomal plaque. Desmoplakin forms rod-like dimers that bind to intermediate filaments and to the cadherin-associated proteins plakoglobin and plakophilin. Gene knock-out experiments have revealed an essential role of desmoplakin in establishing cell-cell contacts in early mouse embryos. 

Figure 3. Intracellular freezing of 8-cell mouse embryos cooled at 20 °C/min in 2 M DMSO. The black "flashing" occurring in cells at -31 °C to -46 °C is characteristic of intracellular ice formation, and is caused by the scattering of light by many small highly branched ice crystals. (Modified from Rail et al., 1983.)...

Rail, W.F., Mazur, P., McGrath, J.J. (1983). Depression of the ice-nucleation temperature of rapidly cooled mouse embryos by glycerol and dimethyl sulfoxide. Biophys. J. 41, 1-12. 

Rail, W.F. (1987). Factors affecting the survival of mouse embryos cryopreserved by vitrification. Cryobiol. 24, 387-402. 

Schneider, U. Mazur, P. (1987). Relative influence of unfrozen fiwition and salt concentration on the survival of slowly frozen eight-cell mouse embryos. Cryobiol. 24, 17-41. 

Szell, A. Shelton, J.N. (1986). Sucrose dilution of glycerol from mouse embryos frozen rapidly in liquid nitrogen vapour. J. Reprod. Pert. 76,401-408. 

Hahnel, A.C., Gifford, D.J., Heikkila, J.J., Schultz, G.A. (1986). Expression of the major heat shock protein hsp70 family during early mouse embryo development Teratogen. Carcinog. Mutagen. 6, 493-510. 

Zeng F, Schultz RM. RNA transcript profiling dnring zygotic gene activation in the preimplantation mouse embryo. Dev Biol 2005 283 40-57. 

Moore MA, Metcalf D. Ontogeny of the haemopoietic system yolk sac origin of in vivo and in vitro colony forming cells in the developing mouse embryo. Br J Haematol 1970 18(3) 279-296. 

Ginsburg, M., Snow, M. H. L., and McLaren, A. (1990). Primordial germ cells in the mouse embryo during gastrulation. Development 110 521-528. 

McConnell, J., and Lee, M. (1989). Presence of cdc2+-like proteins in the preimplantation mouse embryo. Development 107 481-487. 

Candia, A. F., Hu, J Crosby, J Lalley, R A., Noclen, D Nadeau, J., and Wright, C. V. E (1992). Mox-1 and Mox-2 define a novel homeobox gene subfamily and are differentially expressed during early mesodermal patterning in mouse embryos. Development 116 1123-1136. 

Although testicular and ovarian germ cells clearly represent the principal sites of c-mos transcription, lower levels of c-mos expression have been reported in some somatic tissues and cell lines. Propst et al. (1985, 1987) reported low levels of c-mos transcripts in mouse embryos and... 

Hogan, B., Costantini, F., and Lacy, E. (1986). Manipulating the Mouse Embryo. Cold Spring Harbor Laboratory, Cold Spring Harbor, NY. 

Rawles, M. E. (1947). Origin of pigment cells from the neural crest in the mouse embryo. Physiol. Zool. 20 248-266. 

Serbedzija, G. N., Fraser, S. E., and Bronner-Fraser, M. (1990). Pathways of trunk neural crest cell migration in the mouse embryo as revealed by vital dye labelling. Development 108 605-612. 

Kubiak J Z, Ciemerych MA 2001 Cell cycle regulation in early mouse embryos. In The cell cycle and development. Wiley, Chichester (Novartis Found Symp 237) p 79-92... 

Cell cycle regulation in early mouse embryos... 

Special control of the early embryonic cell cycles in the early mouse embryo... 

The first cell cycle of the mouse embryo differs in many respects from the second and the following cell cycles. It is characterized by a long Gl phase that starts after the penetration of the spermatozoon or artificial activation of the oocyte. During this period the chromatin of the oocyte completes the second meiotic division and forms the female pronucleus. At the same time, in the fertilized egg, the highly condensed chromatin of the sperm nucleus decondenses and sperm-specific proteins, protamines, are replaced by histones. After the initial sperm chromatin... 

FIG. 1. Timing and morphology of mouse embryos during the first two cleavages. The cortical activity of the one-cell embryo begins during late G2 phase shortly before the entry into the mitotic M phase. Scheme represents shapes of embryos and morphology of their chromatin and microtubule cytoskeleton. 

The very beginning of the first mitotic cell cycle of the mouse embryo seems to be controlled by the mechanisms characteristic for both meiotic and mitotic cell cycles. Active MAP kinase, its substrate p90rsk and the CSF activity itself could influence the cellular processes within the one-cell embryo. Indeed, we have observed that despite the entry into the interphase (as judged by the low activity of MPF) some proteins are actively phosphorylated as during the meiotic M phase (e.g. 35 kDa complex Howlett et al 1986, Szollosi et al 1993), the nuclei and the microtubule interphase network start to form only 1.5 hours after activation (Szollosi et al 1993). This delay in the phenomena characteristic for the interphase could be linked to the mixed meiotic/mitotic character of this early period. This delay probably allows the correct transformation of the sperm nucleus into the male pronucleus. In species like Xenopus or Drosophila the transitional period between the meiotic and the mitotic cell cycle control is probably much shorter since it is proportional to duration of the short first cell cycle of these rapidly cleaving embryos. Mammalian embryos are perhaps the most suitable to study this transition because of the exceptionally long first embryonic cell cycle. 

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