From a Single Cell to Segmental Structures

Developmental Biology and Larval Ecology ◽

10.1093/oso/9780190648954.003.0001 ◽

2020 ◽

pp. 1-45

Author(s):

Gerhard Scholtz

Keyword(s):

Cell Division ◽

Cell Lineage ◽

Growth Zone ◽

Ventral Side ◽

Molecular Techniques ◽

Germ Band ◽

Band Formation ◽

Division Pattern ◽

Noble Crayfish ◽

Neuronal Precursors

Beginning with Aristotle 2400 years ago, research on crustacean embryology has a long tradition. Rathke’s 1829 landmark study on the noble crayfish initiated modern approaches. Crustaceans in general—and most of their large taxa—show a great diversity in all stages of their developmental pathways from the zygote up to the adult animal. This chapter describes the various modes of cleavage, gastrulation, germ band formation, and segmentation found in crustacean taxa. Cleavage is either total, partial, or mixed. Total cleavage can be indeterminate, without predictable cell lineage; or determinate, with a stereotyped cell division pattern. Gastrulation modes can also vary to a high degree. One finds invagination, epiboly, immigration, delamination, and a mix of some of these. Likewise, the stages of germ layer separation and the number of cells that initiate gastrulation differ. In yolk-rich eggs, a germ disk forms at the future ventral side of the embryo, and the axes and orientation of the germ are recognizable. Through elongation in the anteroposterior direction by a posterior growth zone and intercalary cell divisions, the germ disk is transformed into the germ band. As a result of a unique, stereotyped cell division pattern in the germ band of malacostracans, germ band growth and the segmentation process up to the differentiation of neuronal precursors and early limb anlagen can be analyzed at the level of individual cells. Recent morphological and molecular techniques allow a very detailed spatiotemporal resolution of developmental processes and they offer new perspectives on long-standing morphological questions.

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Cell lineage studies in the crayfish Cherax destructor (Crustacea, Decapoda) : germ band formation, segmentation, and early neurogenesis

Roux s Archives of Developmental Biology ◽

10.1007/bf00364595 ◽

1992 ◽

Vol 202 (1) ◽

pp. 36-48 ◽

Cited By ~ 82

Author(s):

Gerhard Scholtz

Keyword(s):

Cell Lineage ◽

Germ Band ◽

Band Formation ◽

Cherax Destructor ◽

Early Neurogenesis

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Germ band differentiation in the stomatopod Gonodactylaceus falcatus and the origin of the stereotyped cell division pattern in Malacostraca (Crustacea)

Arthropod Structure & Development ◽

10.1016/j.asd.2010.05.006 ◽

2010 ◽

Vol 39 (6) ◽

pp. 411-422 ◽

Cited By ~ 5

Author(s):

Antje H.L. Fischer ◽

Tino Pabst ◽

Gerhard Scholtz

Keyword(s):

Cell Division ◽

Germ Band ◽

Division Pattern

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Cell fate clusters in ICM organoids arise from cell fate heredity and division: a modelling approach

Scientific Reports ◽

10.1038/s41598-020-80141-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Tim Liebisch ◽

Armin Drusko ◽

Biena Mathew ◽

Ernst H. K. Stelzer ◽

Sabine C. Fischer ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Division ◽

Cell Fate ◽

Inner Cell Mass ◽

Cell Mass ◽

Cell Lineage ◽

Cell Fate Decision ◽

Cell Fate Decisions ◽

Chemical Signalling ◽

Fate Decision

AbstractDuring the mammalian preimplantation phase, cells undergo two subsequent cell fate decisions. During the first decision, the trophectoderm and the inner cell mass are formed. Subsequently, the inner cell mass segregates into the epiblast and the primitive endoderm. Inner cell mass organoids represent an experimental model system, mimicking the second cell fate decision. It has been shown that cells of the same fate tend to cluster stronger than expected for random cell fate decisions. Three major processes are hypothesised to contribute to the cell fate arrangements: (1) chemical signalling; (2) cell sorting; and (3) cell proliferation. In order to quantify the influence of cell proliferation on the observed cell lineage type clustering, we developed an agent-based model accounting for mechanical cell–cell interaction, i.e. adhesion and repulsion, cell division, stochastic cell fate decision and cell fate heredity. The model supports the hypothesis that initial cell fate acquisition is a stochastically driven process, taking place in the early development of inner cell mass organoids. Further, we show that the observed neighbourhood structures can emerge solely due to cell fate heredity during cell division.

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When and how does cell division order influence cell allocation to the inner cell mass of the mouse blastocyst?

Development ◽

10.1242/dev.100.2.325 ◽

1987 ◽

Vol 100 (2) ◽

pp. 325-332

Author(s):

C.L. Garbutt ◽

M.H. Johnson ◽

M.A. George

Keyword(s):

Cell Division ◽

Cell Population ◽

Inner Cell Mass ◽

Cell Mass ◽

Cell Lineage ◽

The Other ◽

Mouse Blastocyst ◽

Short Term ◽

Cell Stage ◽

Cell Embryo

Aggregate 8-cell embryos were constructed from four 2/8 pairs of blastomeres, one of which was marked with a short-term cell lineage marker and was also either 4 h older (derived from an early-dividing 4-cell) or 4 h younger (derived from a late-dividing 4-cell) than the other three pairs. The aggregate embryos were cultured to the 16-cell stage, at which time a second marker was used to label the outside cell population. The embryos were then disaggregated and each cell was examined to determine its labelling pattern. From this analysis, we calculated the relative contributions to the inside cell population of the 16-cell embryo of older and younger cells. Older cells were found to contribute preferentially. However, if the construction of the aggregate 8-cell embryo was delayed until each of the contributing 2/8 cell pairs had undergone intercellular flattening and then had been exposed to medium low in calcium to reverse this flattening immediately prior to aggregation, the advantage possessed by the older cells was lost. These results support the suggestion that older cells derived from early-dividing 4-cell blastomeres contribute preferentially to the inner cell mass as a result of being early-flattening cells.

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Expression of engrailed during segmentation in grasshopper and crayfish

Development ◽

10.1242/dev.107.2.201 ◽

1989 ◽

Vol 107 (2) ◽

pp. 201-212 ◽

Cited By ~ 29

Author(s):

N.H. Patel ◽

T.B. Kornberg ◽

C.S. Goodman

Keyword(s):

Monoclonal Antibody ◽

Cell Proliferation ◽

Cell Division ◽

Embryonic Stage ◽

Germ Band ◽

Segmentation Genes ◽

Pair Rule ◽

Drosophila Embryos ◽

The Way

We have used a monoclonal antibody that recognizes engrailed proteins to compare the process of segmentation in grasshopper, crayfish, and Drosophila. Drosophila embryos rapidly generate metameres during an embryonic stage characterized by the absence of cell division. In contrast, many other arthropod embryos, such as those of more primitive insects and crustaceans, generate metameres gradually and sequentially, as cell proliferation causes caudal elongation. In all three organisms, the pattern of engrailed expression at the segmented germ band stage is similar, and the parasegments are the first metameres to form. Nevertheless, the way in which the engrailed pattern is generated differs and reflects the differences in how these organisms generate their metameres. These differences call into question what role homologues of the Drosophila pair-rule segmentation genes might play in other arthropods that generate metameres sequentially.

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Cell lineage in marine nematode Enoplus brevis

Development ◽

10.1242/dev.125.1.143 ◽

1998 ◽

Vol 125 (1) ◽

pp. 143-150

Author(s):

D.A. Voronov ◽

Y.V. Panchin

Keyword(s):

Fluorescent Dyes ◽

Cell Lineage ◽

Cell Types ◽

Ventral Side ◽

Marine Nematode ◽

Cell Stage ◽

Cell Embryo ◽

Multiple Cell ◽

Nerve Muscle ◽

Nematode Development

Early cleavages of the marine nematode Enoplus brevis are symmetrical and occur in synchrony. At the 2- to 16-cell stages, blastomeres are indistinguishable. The progeny of blastomeres was investigated by intracellular injections of fluorescent dyes and horse radish peroxidase. One blastomere of the 2-cell embryo gives rise to a compact group of cells occupying about half of an embryo. The border between labeled and unlabeled cells differs in each embryo dividing it to anterior-posterior, left-right or intermediate parts. At the 8-cell stage, one blastomere gives rise to only endoderm, whereas the other blastomeres produce progeny that form multiple cell types, including nerve, muscle and hypoderm cells, in various proportions. Thus the fates of the blastomeres of early E. brevis embryos, with the exception of the endoderm precursor, are not determined. The process of gastrulation in E. brevis is very similar to that in Caenorhabditis elegans and other nematodes. At the beginning of gastrulation, the 2-celled endoderm precursor lies on the surface of embryo and then sinks inwards. After labeling of cells on the ventral side (near endoderm precursor) at the beginning of gastrulation, their progeny differentiate predominantly into body muscles or pharyngeal cells of the first stage larva. Cells that are located more laterally give rise mainly to neurons. The dorsal blastomeres differentiated principally into hypoderm cells. Our study suggests that a precise cell lineage is not a necessary attribute of nematode development.

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The degree of determination of the early embryo of Schistocerca gregaria (Forskål) (Orthoptera: Acrididae)

Development ◽

10.1242/dev.25.3.277 ◽

1971 ◽

Vol 25 (3) ◽

pp. 277-299

Author(s):

S. K. Moloo

Keyword(s):

Early Development ◽

Schistocerca Gregaria ◽

Early Embryo ◽

Germ Band ◽

Early Cleavage ◽

Band Formation ◽

Zygote Nucleus ◽

Young Embryo ◽

Blastoderm Stage

The degree of determination of the young embryo of S. gregaria has been investigated using ligation, thermocautery and centrifugation techniques. From the overall results, it is suggested that the early development of the embryo is mediated by two physiological centres. The formation of the germ rudiment is controlled by an activation centre located in the periplasm round the posterior end of the egg. This centre is already present at the zygote nucleus stage and is essential during the very early cleavage period. The differentiation of the germ band is induced by the activity of a second centre, the differentiation centre, located in the presumptive thorax. It apparently becomes established at least by the late blastoderm stage and its activity continues during the period of germ-band formation. During the late cleavage and early blastoderm stages, the egg is labile and the embryo is therefore able to normalize its development after part or parts of the germinal Anlage have been cauterized, removed or displaced. The differentiation centre completes its functions by the beginning of gastrulation. Thereafter, the embryo is determined. The embryo can regulate its size at least up to the gastrulation stage provided that a certain minimum amount of usable yolk is available. The development of the serosa is not under the control of either centre. This structure seems to be capable of regeneration providing that a part of the extra-embryonic blastoderm remains intact.

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The use of ‘normal’ and ‘transformed’ gynandromorphs in mapping the primordial germ cells and the gonadal mesoderm in Drosophila

Development ◽

10.1242/dev.35.3.607 ◽

1976 ◽

Vol 35 (3) ◽

pp. 607-616

Author(s):

W. J. Gehring ◽

E. Wieschaus ◽

M. Holliger

Keyword(s):

Germ Cells ◽

Primordial Germ Cells ◽

Cell Lineage ◽

Ventral Side ◽

Drosophila Embryo ◽

The Real ◽

Genital Disc ◽

Stage Of Development ◽

Data Support ◽

Blastoderm Stage

The primordial germ cells and the gonadal mesoderm were mapped in the Drosophila embryo by analyzing the patterns of mosaicism in ‘normal’ and ‘transformed’ gynandromorphs. Relative to the adult cuticular markers the germ cells map as the posterior moststructure, which coincides with their known location in the blastoderm embryo. These data support the hypothesis that the gynandromorph map reflects the real position of the pri-mordia in the embryo. Since after the blastoderm stage the primordial germ cells migrateanteriorly these data also indicate that the map in fact corresponds to the blastoderm stageand not to a later stage of development. The genital disc maps as a single median primordium anterior and ventral to the germ cells, the gonadal mesoderm is located anterior to the genital disc and also forms a single median primordium on the ventral side of the embryo. The primordia for the genital disc and the gonadal mesoderm are unusually large in size, which presumably reflects some indeterminacy of the cell lineage leading to an ‘expansion’ of the map.

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