Journal:

Article Title: Role of Cdx2 and cell polarity in cell allocation and specification of trophectoderm and inner cell mass in the mouse embryo

doi: 10.1101/gad.486108

Figure Lengend Snippet: Elevation of Cdx2 expression promotes symmetric divisions. Cdx2 was overexpressed in one late two-cell/early four-cell blastomere, and embryos were followed by time-lapse microscopy to the blastocyst stage (two sample embryos shown in A–G and H–N). In controls, DsRed mRNA only was injected (O–V). Lineages were generated with SIMI Biocell software, and the centers of the nuclei from each clone are marked either red (injected clone) or blue (wild-type clone). From 16-cell onward, nuclei of inside cells are marked yellow (injected clone) or light blue (wild-type clone); see W for coding. Cdx2 expression leads to significantly more symmetric than asymmetric divisions (indicated by the relative numbers of yellow versus light blue cells). Merged 3D representations and DIC images from three different embryos are shown in A–G, H–N, and O–V. Times of images are in minutes. Schematic representation of lineage trees was generated with SIMI Biocell software (X; embryo A–G, Y; embryo H–N). (Z) Proportions of symmetric or asymmetric divisions taken by clones expressing injected Cdx2 mRNA or DsRed mRNA relative to the clone derived from the noninjected cell (see also Supplemental Table 2).

Article Snippet: Schematic representation of lineage trees was generated with SIMI Biocell software (X; embryo A – G , Y; embryo H – N ). ( Z ) Proportions of symmetric or asymmetric divisions taken by clones expressing injected Cdx2 mRNA or DsRed mRNA relative to the clone derived from the noninjected cell (see also Supplemental Table 2).

Techniques: Expressing, Time-lapse Microscopy, Injection, Generated, Software, Clone Assay, Derivative Assay

Journal:

Article Title: Role of Cdx2 and cell polarity in cell allocation and specification of trophectoderm and inner cell mass in the mouse embryo

doi: 10.1101/gad.486108

Figure Lengend Snippet: Down-regulation of Cdx2 expression leads to a reduced contribution to the trophectoderm. Cdx2 was down-regulated in half of the embryo by dsRNA injection to one blastomere. (A–H) Sections through fixed and immunocytochemically stained embryos at the morula (A–D) and blastocyst (E–H) stage show specific knockdown of Cdx2 protein in the injected clone; the white dashed line indicates injected cell progeny. (I) Schematic of lineage trees generated with SIMI Biocell software. (J–O) Embryos were followed by time-lapse microscopy to the blastocyst stage. Merged 3D representations and DIC images are shown; times of images are in minutes. Color-coding as in Figure 2. (P) Proportions of symmetric/asymmetric divisions taken by the Cdx2 RNAi-injected clone relative to the wild-type clone at fourth and fifth cleavage rounds (see also Supplemental Table 3A).

Article Snippet: Schematic representation of lineage trees was generated with SIMI Biocell software (X; embryo A – G , Y; embryo H – N ). ( Z ) Proportions of symmetric or asymmetric divisions taken by clones expressing injected Cdx2 mRNA or DsRed mRNA relative to the clone derived from the noninjected cell (see also Supplemental Table 2).

Techniques: Expressing, Injection, Staining, Knockdown, Generated, Software, Time-lapse Microscopy

Journal: BMC Biology

Article Title: High-precision morphology: bifocal 4D-microscopy enables the comparison of detailed cell lineages of two chordate species separated for more than 525 million years

doi: 10.1186/s12915-015-0218-1

Figure Lengend Snippet: Cell lineage trees of the developments of a larvacean ( left , Oikopleura dioica ) and an ascidian ( right , Phallusia mammillata ) embryo. Different colors denote different tissue fates. Note the different time scales. Blue dotted line indicates respective timeline of stages depicted in Fig. . For the black lines , tissue fate was either not restricted to a single fate yet or a confident determination was not possible at the latest stage documented. Branches in the trees are arranged according to the same scheme (see first paragraph of “ ” for details)

Article Snippet: The simultaneous comparative analysis of two tunicate species using the same analytical software (Simi Biocell, Simi Reality Motion Systems GmbH, Unterschleißheim, Germany) and a similar recording technique, and therefore the same level of precision, allowed for an improved re-analysis of the previously reported cell lineage of the larvacean Oikopleura dioica (Fig. ), enabling improvements over the original cell lineage results reported in [ ] for the larvacean, while adding a cell lineage in an ascidian species, Phallusia mammillata (Fig. ), at unprecedented precision.

Techniques:

Journal: BMC Biology

Article Title: High-precision morphology: bifocal 4D-microscopy enables the comparison of detailed cell lineages of two chordate species separated for more than 525 million years

doi: 10.1186/s12915-015-0218-1

Figure Lengend Snippet: Differential interference contrast images and schematic cell position representations at comparable late gastrula stages in an ascidian embryo ( upper part ) and in a larvacean embryo (l ower part ). Axis orientation labels next to images indicate orientations: a anterior, a n animal, l left, p posterior, r right, v vegetal. Absolute age is indicated by the blue dotted lines in Fig. ; tissue fates are color coded as in Fig. . Note the similarity in the relative positions of the different tissues, despite the considerably lower cell number in the larvacean. Note also that prospective nervous system cells ( yellow ) are arranged as a neural plate at the anterior border of the blastopore in the ascidian whereas the corresponding cells have already ingressed (neurulated) in the larvacean. (For detailed spatial and temporal resolution of neural fate restrictions in the two species see Additional files , , and ). bp , blastopore

Article Snippet: The simultaneous comparative analysis of two tunicate species using the same analytical software (Simi Biocell, Simi Reality Motion Systems GmbH, Unterschleißheim, Germany) and a similar recording technique, and therefore the same level of precision, allowed for an improved re-analysis of the previously reported cell lineage of the larvacean Oikopleura dioica (Fig. ), enabling improvements over the original cell lineage results reported in [ ] for the larvacean, while adding a cell lineage in an ascidian species, Phallusia mammillata (Fig. ), at unprecedented precision.

Techniques:

Journal: BMC Biology

Article Title: High-precision morphology: bifocal 4D-microscopy enables the comparison of detailed cell lineages of two chordate species separated for more than 525 million years

doi: 10.1186/s12915-015-0218-1

Figure Lengend Snippet: To increase resolution, only the upper halves (left of the embryo) of cell lineage trees from Fig. are magnified. Left : the larvacean Oikopleura dioica , right : the ascidian Phallusia mammillata . Different colors denote different tissue fates. Note the different time scales. For the black lines , tissue fate was either not restricted to a single fate yet or a confident determination was not possible at the latest stage documented. Branches in the trees are arranged according to the same scheme (see first paragraph of “ ” for details)

Article Snippet: The simultaneous comparative analysis of two tunicate species using the same analytical software (Simi Biocell, Simi Reality Motion Systems GmbH, Unterschleißheim, Germany) and a similar recording technique, and therefore the same level of precision, allowed for an improved re-analysis of the previously reported cell lineage of the larvacean Oikopleura dioica (Fig. ), enabling improvements over the original cell lineage results reported in [ ] for the larvacean, while adding a cell lineage in an ascidian species, Phallusia mammillata (Fig. ), at unprecedented precision.

Techniques:

Journal: BMC Biology

Article Title: High-precision morphology: bifocal 4D-microscopy enables the comparison of detailed cell lineages of two chordate species separated for more than 525 million years

doi: 10.1186/s12915-015-0218-1

Figure Lengend Snippet: To the left the ascidian embryo at 235 min post fertilization (pf) consists of 64 cells. To the right the larvacean embryo at 80 min pf consists of 30 cells. The individual cells in each column are named and marked red in the respective schematic representation. Upper row : schematic representation of embryo at the late blastula stage in lateral view from the right side, anterior is to the right of the image. Middle row : differential interference contrast images marking the nucleus of the respective cell, in vegetal view, anterior is to the right of the images. Lines mark cell movement to the next generation of cells, i.e., to the next mitosis until the following one. Lower row : same images as in the upper row, but with the movement as described for the middle row overlain. This lateral view maximizes the relative visible movements of the cells. Graph below images : Movement profile of individual cells at the onset of gastrulation. Relative distances are indicated as measured directly from lower row of images. Measured distances are distances moved along the animal–vegetal axis from start to end of lines shown in middle row. Axis orientation label: a anterior, a n animal, l left, p posterior, r right, v vegetal

Article Snippet: The simultaneous comparative analysis of two tunicate species using the same analytical software (Simi Biocell, Simi Reality Motion Systems GmbH, Unterschleißheim, Germany) and a similar recording technique, and therefore the same level of precision, allowed for an improved re-analysis of the previously reported cell lineage of the larvacean Oikopleura dioica (Fig. ), enabling improvements over the original cell lineage results reported in [ ] for the larvacean, while adding a cell lineage in an ascidian species, Phallusia mammillata (Fig. ), at unprecedented precision.

Techniques:

Journal: BMC Biology

Article Title: High-precision morphology: bifocal 4D-microscopy enables the comparison of detailed cell lineages of two chordate species separated for more than 525 million years

doi: 10.1186/s12915-015-0218-1

Figure Lengend Snippet: Selected tracings of individual cells from the animal half of the embryo. The cells indicated on top of each column are marked red in the schematic representation and the descendants of the respective cells are seen in red in the lower rows. The intermediary Differential interference contrast image shows the cell divisions and cell movements of the respective cells. Numbers are minutes post fertilization. Nomarski images are all in the same orientation. Axis orientation labels in images indicate orientations: a anterior, a n animal, d dorsal, l left, p posterior, r right, v vegetal, v e ventral. Upper panel : Oikopleura dioica. Lower panel : Phallusia mammillata . The right-most column details the mitotic history of cell line a9.49 that has been hypothesized to be homologous to vertebrate neural crest cells

Article Snippet: The simultaneous comparative analysis of two tunicate species using the same analytical software (Simi Biocell, Simi Reality Motion Systems GmbH, Unterschleißheim, Germany) and a similar recording technique, and therefore the same level of precision, allowed for an improved re-analysis of the previously reported cell lineage of the larvacean Oikopleura dioica (Fig. ), enabling improvements over the original cell lineage results reported in [ ] for the larvacean, while adding a cell lineage in an ascidian species, Phallusia mammillata (Fig. ), at unprecedented precision.

Techniques: