scholarly journals Blastomeres arising from the first cleavage division have distinguishable fates in normal mouse development

Development ◽  
2001 ◽  
Vol 128 (19) ◽  
pp. 3739-3748 ◽  
Author(s):  
Karolina Piotrowska ◽  
Florence Wianny ◽  
Roger A. Pedersen ◽  
Magdalena Zernicka-Goetz
Keyword(s):  
Inner Cell Mass ◽  
Angular Displacement ◽  
Cell Mass ◽  
Boundary Region ◽  
Lineage Tracing ◽  
Mouse Development ◽  
Cleavage Division ◽  
Cell Stage ◽  
Early Embryos ◽  
Cell Mouse Embryo

Two independent studies have recently suggested similar models in which the embryonic and abembryonic parts of the mouse blastocyst become separated already by the first cleavage division. However, no lineage tracing studies carried out so far on early embryos provide the support for such a hypothesis. Thus, to re-examine the fate of blastomeres of the two-cell mouse embryo, we have undertaken lineage tracing studies using a non-perturbing method. We show that two-cell stage blastomeres have a strong tendency to develop into cells that comprise either the embryonic or the abembryonic parts of the blastocyst. Moreover, the two-cell stage blastomere that is first to divide will preferentially contribute its progeny to the embryonic part. Nevertheless, we find that the blastocyst embryonic-abembryonic axis is not perfectly orthogonal to the first cleavage plane, but often shows some angular displacement from it. Consequently, there is a boundary zone adjacent to the interior margin of the blastocoel that is populated by cells derived from both earlier and later dividing blastomeres. The majority of cells that inhabit this boundary region are, however, derived from the later dividing two-cell stage blastomere that contributes predominantly to the abembryonic part of the blastocyst. Thus, at the two-cell stage it is already possible to predict which cell will contribute a greater proportion of its progeny to the abembryonic part of the blastocyst (region including the blastocyst cavity) and which to the embryonic part (region containing the inner cell mass) that will give rise to the embryo proper.

Features of cell lineage in preimplantation mouse development

Development ◽  
1978 ◽  
Vol 48 (1) ◽  
pp. 53-72
Author(s):  
C. F. Graham ◽  
Z. A. Deussen
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Cell Lineage ◽  
The Other ◽  
Mouse Development ◽  
Cell Stage ◽  
Daughter Cells ◽  
Preimplantation Mouse ◽  
Peripheral Cells

The cell lineage of the mouse was studied from the 2-cell stage to the blastocyst. Lineage to the 8-cell stage was followed under the microscope. Each cell from the 2-cell stage divided to form two daughter cells which remained attached. Subsequently, these two daughters each produced two descendants; one of these descendants regularly lay deep in the structure of the embryo while the other was peripheral. Lineage to the blastocyst was followed by injecting oil drops into cells at the 8-cell stage, and then following the segregation of these drops into the inner cell mass and trophectoderm. Between the 8-cell stage and the blastocyst, the deep cells contributed more frequently to the inner cell mass than did the peripheral cells.

105 THE Oct4/Cdx2 EXPRESSION AND CELL FATE OF INDIVIDUAL TWO-CELL BLASTOMERES IN TWO MOUSE STRAINS

2008 ◽  
Vol 20 (1) ◽  
pp. 133
Author(s):  
M. Katayama ◽  
R. M. Roberts
Keyword(s):  
Cell Mass ◽  
Strain Differences ◽  
Lineage Tracing ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Mouse Strains ◽  
Mouse Development ◽  
Cell Stage ◽  
Developmental Potential ◽  
Nih Swiss

Fertile adults and occasionally twins have been derived from murine blastomeres at the 2-cell stage, indicating that such blastomeres may be equivalently totipotent, but there are conflicting reports that individual blastomeres from 2-cell stage murine conceptuses make different contributions to the embryonic and abembryonic regions of the blastocyst, implying that they differ in developmental potential. Here, we have re-examined this subject using 2 mouse strains, CF1 and NIH Swiss (SW), and 2 experimental approaches, random blastomere destruction at the 2-cell stage by repeated insertion of a needle into its nucleus and lineage tracing with the dye, DiI-CM. The manipulated conceptuses and untreated controls were cultured in KSOM-AA to morula and blastocyst stages (84 or 108 h pc, respectively), fixed, and immunostained for Oct4 and Cdx2. Antigen distribution, number of nuclei (stained by 42,6-diamidino-2-phenylindole), and cell progeny labeled with DiI-CM were examined by confocal laser scanning microscopy. Cell numbers are means � SD and were analyzed by a Student t-test. Cells positive for Cdx2 were assumed to represent trophectoderm or trophectoderm precursors, ones positive for Oct4 but negative for Cdx2 (Oct+Cdx–) inner cell mass. Ablation of a blastomere failed to prevent developmental progression in either strain, but the total number of cells at both morula (SW 11.4 � 3.3 v. 19.2 � 7.1; CF1 10.1 � 2.5 v. 22.1 � 6.4) and blastocyst (SW 48.6 � 7.4 v. 69.4 � 9.9; CF1 24.8 � 6.2 v. 53.8 � 13.5) was significantly reduced. In SW, the average fraction of Oct+Cdx– cells after blastomere ablation was significantly lower (P < 0.05) than in controls in morulae (0.47 � 0.2 v. 0.65 � 0.1) but not in blastocysts (0.33 � 0.1 and 0.34 � 0.1). In CF1, the fraction of Oct+Cdx– cells was lower (P < 0.05) than controls in both morulae and blastocysts (0.31 � 0.2 v. 0.58 � 0.2 and 0.18 � 0.1 v. 0.27 � 0.04, respectively). The CF1 morulae fell mainly into 2 groups, one low fraction (≤0.3, 54%) of Oct+Cdx– cells and the other with a more normal fraction (0.3 to 0.8, 43%) relative to controls. A majority of NIH Swiss morulae had an Oct+Cdx– cell fraction >0.4 and in this respect resembled controls. We then examined these strain differences by lineage tracing. The majority of SW blastocysts (65%, n = 34) demonstrated a random localization of DiI-labeled cell progeny (i.e., there was no preferential distribution of labeled cells to either the embryonic or abembryonic poles). By contrast, in CF1 (n = 38), 32% of blastocysts had labeled cells confined to their embryonic end and 42% with DiI-labeled, Cdx2-positive cells clustered at the abembryonic locale. A random localization was observed in 26% of blastocysts. In conclusion, these data confirm that there is plasticity in early mouse development but also suggest that in CF1, but not in SW conceptuses, blastomeres at the 2-cell stage differ in their abilities to contribute to the embryonic pole. Similar strain differences may explain the disagreements among studies on lineage tracing in early cleavage stage conceptuses.

scholarly journals G9a regulates temporal preimplantation developmental program and lineage segregation in blastocyst

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Jan J Zylicz ◽  
Maud Borensztein ◽  
Frederick CK Wong ◽  
Yun Huang ◽  
Caroline Lee ◽  
...  
Keyword(s):  
Cell Fate ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Blastocyst Stage ◽  
Vital Role ◽  
Mouse Development ◽  
Cell Stage ◽  
Developmental Progression ◽  
Early Mouse ◽  
The Impact

Early mouse development is regulated and accompanied by dynamic changes in chromatin modifications, including G9a-mediated histone H3 lysine 9 dimethylation (H3K9me2). Previously, we provided insights into its role in post-implantation development (Zylicz et al., 2015). Here we explore the impact of depleting the maternally inherited G9a in oocytes on development shortly after fertilisation. We show that G9a accumulates typically at 4 to 8 cell stage to promote timely repression of a subset of 4 cell stage-specific genes. Loss of maternal inheritance of G9a disrupts the gene regulatory network resulting in developmental delay and destabilisation of inner cell mass lineages by the late blastocyst stage. Our results indicate a vital role of this maternally inherited epigenetic regulator in creating conducive conditions for developmental progression and on cell fate choices.

Cytokeratin filament assembly in the preimplantation mouse embryo

Development ◽  
1987 ◽  
Vol 101 (3) ◽  
pp. 565-582 ◽  
Author(s):  
J.C. Chisholm ◽  
E. Houliston
Keyword(s):  
Mouse Embryo ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Blastocyst Stage ◽  
Lineage Tracing ◽  
Cell Stage ◽  
Filament Assembly ◽  
Filament Networks ◽  
Tracing Techniques ◽  
Cytokeratin Filaments

The timing, spatial distribution and control of cytokeratin assembly during mouse early development has been studied using a monoclonal antibody, TROMA-1, which recognizes a 55,000 Mr trophectodermal cytokeratin (ENDO A). This protein was first detected in immunoblots at the 4-cell stage, and became more abundant at the 16-cell stage and later. Immunofluorescence analysis revealed assembled cytokeratin filaments in some 8-cell blastomeres, but not at earlier stages. At the 16-cell stage, filaments were found in both polarized (presumptive trophectoderm; TE) and apolar (presumptive inner cell mass; ICM) cells in similar proportions, although polarized cells possessed more filaments than apolar cells. By the late 32-cell, early blastocyst, stage, all polarized (TE) cells contained extensive filament networks whereas cells positioned inside the embryo tended to have lost their filaments. The presence of filaments in inside cells at the 16-cell stage and in ICM cells was confirmed by immunoelectron microscopy. Lineage tracing techniques demonstrated that those cells in the ICM of early blastocysts which did possess filaments were almost exclusively the progeny of polar 16-cell blastomeres, suggesting that these filaments were directly inherited from outside cells at the 16- to 32-cell transition. Inhibitor studies revealed that proximate protein synthesis but not mRNA synthesis is required for filament assembly at the 8-cell stage. These results demonstrate that there are quantitative rather than qualitative differences in the expression of cytokeratin filaments in the inner cell mass and trophectoderm cells of the mouse embryo.

Activins are expressed in preimplantation mouse embryos and in ES and EC cells and are regulated on their differentiation

Development ◽  
1993 ◽  
Vol 117 (2) ◽  
pp. 711-723 ◽  
Author(s):  
R.M. Albano ◽  
N. Groome ◽  
J.C. Smith
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Alpha Subunit ◽  
Beta Subunits ◽  
Mouse Development ◽  
Cell Stage ◽  
Mammalian Embryo ◽  
Mesoderm Formation ◽  
Ec Cells ◽  
Early Mouse

Members of the activin family have been suggested to act as mesoderm-inducing factors during early amphibian development. Little is known, however, about mesoderm formation in the mammalian embryo, and as one approach to investigating this we have studied activin expression during early mouse development. Activins are homo- or heterodimers of the beta A or beta B subunits of inhibin, itself a heterodimer consisting of one of the beta subunits together with an alpha subunit. Our results indicate that the oocyte contains mRNA encoding all three subunits, and antibody staining demonstrates the presence of both alpha and beta protein chains. From the fertilized egg stage onwards, alpha subunit protein cannot be detected, so the presence of beta subunits reflects the presence of activin rather than inhibin. Maternal levels of activin protein decline during early cleavage stages but increase, presumably due to zygotic transcription (see below), in the compacted morula. By 3.5 days, only the inner cell mass (ICM) cells of the blastocyst express activin, but at 4.5 days the situation is reversed; activin expression is confined to the trophectoderm. Using reverse transcription-PCR, neither beta A nor beta B mRNA was detectable at the two-cell stage but transcripts encoding both subunits were detectable at the morula stage, with beta B mRNA persisting into the blastocyst. We have also analyzed activin and inhibin expression in ES and EC cells. Consistent with the observation that activins are expressed in the ICM of 3.5-day blastocysts, we find high levels of beta A and beta B mRNA in all eight ES cell lines tested. F9 EC cells express only activin beta B, together with low levels of the inhibin alpha chain. When ES and EC cells are induced to differentiate, levels of activin fall dramatically. These results are consistent with a role for activins in mesoderm formation and other steps of early mouse development.

scholarly journals DNA methylation pattern in human zygotes and developing embryos

Reproduction ◽  
2004 ◽  
Vol 128 (6) ◽  
pp. 703-708 ◽  
Author(s):  
Helena Fulka ◽  
Milan Mrazek ◽  
Olga Tepla ◽  
Josef Fulka
Keyword(s):  
Dna Methylation ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Methylation Pattern ◽  
Blastocyst Stage ◽  
The Other ◽  
Cell Stage ◽  
Global Methylation ◽  
Early Embryos ◽  
Human Zygotes

We report on observations of the global methylation/demethylation pattern of both pronuclei in human zygotes and in early embryos up to the blastocyst stage. Our results demonstrate that in about half of the zygotes examined the paternal chromatin was less methylated than the maternal chromatin. In the other half, both pronuclei exhibited the same intensity of labeling. The nuclei in developing embryos were intensively labeled for up to the four-cell stage; thereafter, a decline of labeling intensity was detected. Remethylation in some nuclei starts in late morulae. Surprisingly, and unlike the mouse, at the blastocyst stage the inner cell mass showed a weaker intensity of labeling than the trophectodermal cells.

158 LEADING BLASTOMERE OF A 2-CELL-STAGE PORCINE PARTHENOGENETIC EMBRYO CONTRIBUTES TO TROPHECTODERM FIRST

2007 ◽  
Vol 19 (1) ◽  
pp. 196
Author(s):  
C. Won ◽  
S. K. Park ◽  
Y.-J. Choi ◽  
H. Kang ◽  
S. Roh
Keyword(s):  
Technology Development ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Normal Animal ◽  
Development Project ◽  
Lineage Tracing ◽  
Axis Formation ◽  
Cell Stage ◽  
Lipid Contents

Embryonic axis formation is important in normal animal development. Some vertebrate and invertebrate eggs display undeniable polarity along a plane known as the animal–vegetal axis. However, axis formation in mammals, which is studied only in mice, is still a point of issue (Hiiragi and Solter 2004 Nature 430, 360–364; Zernicka-Goetz et al. 2005 Nature 434, 391–395). In the present study, we investigated the embryonic–abembryonic axis formation in porcine species. We used porcine parthenogenetic embryos to prevent a topological change of the 2 apposing pronuclei in the egg center caused by polyspermy and to avoid the influence of the fertilization cone, which indicates the sperm entry position. For lineage tracing, DiI, a lipophilic fluorescence dye, was injected into one blastomere per embryo at the 2-cell stage. After this process, as embryos developed into the 3-cell stage, all the embryos were divided into 2 groups named Leading and Lagging, following the location of the DiI oil drop (Leading: the oil drop was positioned in the first-dividing blastomere; Lagging: the drop was positioned in the late-dividing blastomere). The embryos developed into blastocysts after 6 to 7 days of culture in vitro. Only the inner cell mass (ICM) was labeled in 50% (8/16) of the Lagging group. In some Lagging embryos (2/16), ICMs with a small portion of adjacent trophectodermal cells (TE) were labeled and 62.5% (10/16) of Lagging embryos formed the ICM part in total. On the other hand, 60% (6/10) of the Leading embryos formed only distal TE (opposite side of the ICM). Only one of the Leading embryos formed the ICM. The rest of Lagging embryos (37.5%, 6/16) or the Leading group (40.0%, 4/10) showed an even distribution of blastocysts, regardless of the ICM or TE. Oocytes, zygotes, and 2-cell-stage embryos in porcine species tended to show unequally distributed lipid contents and could be distinguished by their different colors and brightness, although not all of them showed significant differences. We injected DiI into a relatively brighter blastomere of the 2-cell-stage embryos and the results were very similar to those obtained from the Leading group (distal TE: 70.6%, 24/34). High lipid contents may be the cause of delayed development of the blastomere of an embryo. Our findings indicated that the Leading blastomere of 2-cell porcine parthenotes formed distal TE first, and that afterward, the Lagging blastomere not only filled the rest of the TE but also contributed to the ICM. This study was supported by the Research Project on the Production of Bio-organs (No. 200506030601) and Technology Developmental Program (High-Technology Development Project No. 204117-3) for Agriculture and Forestry, Ministry of Agriculture and Forestry, Republic of Korea

Two CDC25 homologues are differentially expressed during mouse development

Development ◽  
1995 ◽  
Vol 121 (7) ◽  
pp. 2047-2056 ◽  
Author(s):  
D. Wickramasinghe ◽  
S. Becker ◽  
M.K. Ernst ◽  
J.L. Resnick ◽  
J.M. Centanni ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Developmental Expression ◽  
Preimplantation Embryos ◽  
Mouse Development ◽  
Cell Stage ◽  
Phosphatase Domain ◽  
Cell Cycles ◽  
Stage Of Development ◽  
Drosophila Homolog

The cdc25 gene product is a tyrosine phosphatase that acts as an initiator of M-phase in eukaryotic cell cycles by activating p34cdc2. Here we describe the cloning and characterization of the developmental expression pattern of two mouse cdc25 homologs. Sequence comparison of the mouse genes with human CDC25 genes reveal that they are most likely the mouse homologs of human CDC25A and CDC25B respectively. Mouse cdc25a, which has not been described previously, shares 84% sequence identity with human CDC25A and has a highly conserved phosphatase domain characteristic of all cdc25 genes. A glutathione-S-transferase-cdc25a fusion protein can hydrolyze para-nitro-phenylphosphate confirming that cdc25a is a phosphatase. In adult mice, cdc25a transcripts are expressed at high levels in the testis and at lower levels in the ovary, particularly in germ cells; a pattern similar to that of twn, a Drosophila homolog of cdc25. Lower levels of transcript are also observed in kidney, liver, heart and muscle, a transcription pattern that partially overlaps, but is distinct from that of cdc25b. Similarly, in the postimplantation embryo cdc25a transcripts are expressed in a pattern that differs from that of cdc25b. cdc25a expression is observed in most developing embryonic organs while cdc25b expression is more restricted. An extended analysis of cdc25a and cdc25b expression in preimplantation embryos has also been carried out. These studies reveal that cdc25b transcripts are expressed in the one-cell embryo, decline at the two-cell stage and are re-expressed at the four-cell stage, following the switch from maternal to zygotic transcription which mirrors the expression of string, another Drosophila homolog of cdc25. In comparison, cdc25a is not expressed in the preimplantation embryo until the late blastocyst stage of development, correlating with the establishment of a more typical G1 phase in the embryonic cell cycles. Both cdc25a and cdc25b transcripts are expressed at high levels in the inner cell mass and the trophectoderm, which proliferate rapidly prior to implantation. These data suggest the cdc25 genes may have distinct roles in regulating the pattern of cell division during mouse embryogensis and gametogenesis.

scholarly journals Origin of cellular asymmetries in the pre-implantation mouse embryo: a hypothesis

2014 ◽  
Vol 369 (1657) ◽  
pp. 20130536 ◽  
Author(s):  
Katsuyoshi Takaoka ◽  
Hiroshi Hamada
Keyword(s):  
Dna Methylation ◽  
Cell Fate ◽  
Inner Cell Mass ◽  
Cell Mass ◽  
Cell Fate Decision ◽  
Mouse Development ◽  
Cell Stage ◽  
Stage Embryo ◽  
A Cell ◽  
Fate Decision

The first cell fate decision during mouse development concerns whether a blastomere will contribute to the inner cell mass (ICM; which gives rise to the embryo proper) or to trophectoderm (TE; which gives rise to the placenta). The position of a cell within an 8- to 16-cell-stage embryo correlates with its future fate, with outer cells contributing to TE and inner cells to the ICM. It remains unknown, however, whether an earlier pre-pattern exists. Here, we propose a hypothesis that could account for generation of such a pre-pattern and which is based on epigenetic asymmetry (such as in histone or DNA methylation) between maternal and paternal genomes in the zygote.

scholarly journals Totipotency of mouse zygotes extends to single blastomeres of embryos at the four-cell stage

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marino Maemura ◽  
Hiroaki Taketsuru ◽  
Yuki Nakajima ◽  
Ruiqi Shao ◽  
Ayaka Kakihara ◽  
...  
Keyword(s):  
Inner Cell Mass ◽  
Cell Mass ◽  
Mouse Embryos ◽  
Primitive Endoderm ◽  
Cell Stage ◽  
Supportive Environment ◽  
Mouse Zygotes ◽  
Single Blastomeres ◽  
Multicellular Organisms

AbstractIn multicellular organisms, oocytes and sperm undergo fusion during fertilization and the resulting zygote gives rise to a new individual. The ability of zygotes to produce a fully formed individual from a single cell when placed in a supportive environment is known as totipotency. Given that totipotent cells are the source of all multicellular organisms, a better understanding of totipotency may have a wide-ranging impact on biology. The precise delineation of totipotent cells in mammals has remained elusive, however, although zygotes and single blastomeres of embryos at the two-cell stage have been thought to be the only totipotent cells in mice. We now show that a single blastomere of two- or four-cell mouse embryos can give rise to a fertile adult when placed in a uterus, even though blastomere isolation disturbs the transcriptome of derived embryos. Single blastomeres isolated from embryos at the eight-cell or morula stages and cultured in vitro manifested pronounced defects in the formation of epiblast and primitive endoderm by the inner cell mass and in the development of blastocysts, respectively. Our results thus indicate that totipotency of mouse zygotes extends to single blastomeres of embryos at the four-cell stage.

Sign in / Sign up

Export Citation Format

Share Document