From DNA transcription to visible structure: What the development of multicellular animals teaches us
Acta Biotheoretica 36 (2) (1987)
|Abstract||This article is concerned with the problem of the relation between the genetic information contained in the DNA and the emergence of visible structure in multicellular animals. The answer is sought in a reappraisal of the data of experimental embryology, considering molecular, cellular and organismal aspects. The presence of specific molecules only confers a tissue identity on the cells when their concentration exceeds the threshold of differentiation. When this condition is not fulfilled the activity of the genes that code for the specific molecules in question only confers on them a histogenetic potency, i.e. the capacity to form the corresponding tissue in further development (or to transdifferentiate to that tissue). The progressive restriction of histogenetic potencies during development reflects the irreversible repression of more and more genes. The establishment of a given tissue identity under the influence of an inducing tissue (or a morphogenetic hormone) is only possible when the cells have acquired the competence to respond. Tissue differentiation proceeds progressively during development thanks to the cytoplasmic memory that cells retain collectively (or sometimes individually) of the items of information successively registered by their ancestors cells. The increasing complexity of visible structure emerging during development results only from the progression of tissue differentiation. This involves continual exchange of information among the cells and leads to (1) cell displacements and rearrangements, particularly during organogenesis and (2) extreme diversification of cell individualities within tissues, particularly during postembryonic growth. A mutation (just as a teratogenic factor) evokes an anomaly that is localized in both space and time because it alters a certain aspect of cell behaviour (particularly cell surface adhesiveness or mitotic activity) at the time when this is involved in the establishment of a particular structural trait. Neither the organization of the adult nor the modalities of development are encoded in the DNA. The automatic concatenation of cell interactions in the embryo and the structural amplification it entails is conditioned by the specific biochemical composition of the cytoplasm of the egg and by the heterogeneous distribution of its inclusions.|
|Keywords||No keywords specified (fix it)|
|Through your library||Configure|
Similar books and articles
Joachim W. Ellwart & Peter Dörmer (1992). Measurement of Efflux From G1-Phase in a Growth Factor Dependent Cell Line. Acta Biotheoretica 40 (2-3).
Brian K. Hall (2003). Unlocking the Black Box Between Genotype and Phenotype: Cell Condensations as Morphogenetic (Modular) Units. Biology and Philosophy 18 (2).
Jacques Demongeot (2009). Biological Boundaries and Biological Age. Acta Biotheoretica 57 (4).
Melinda B. Fagan (2011). Social Experiments in Stem Cell Biology. Perspectives on Science 19 (3):235-262.
Jürgen Bereiter-Hahn (1985). Architecture of Tissue Cells the Structural Basis Which Determines Shape and Locomotion of Cells. Acta Biotheoretica 34 (2-4).
François Leitner, Sylvain Paillasson, Xavier Ronot & Jacques Demongeot (1995). Dynamic Functional and Structural Analysis of Living Cells: New Tools for Vital Staining of Nuclear DNA and for Characterisation of Cell Motion. Acta Biotheoretica 43 (4).
Loïc Forest & Jacques Demongeot (forthcoming). A General Formalism for Tissue Morphogenesis Based on Cellular Dynamics and Control System Interactions. Acta Biotheoretica.
José Pierrez & Xavier Ronot (1992). Flow Cytometric Analysis of the Cell Cycle: Mathematical Modeling and Biological Interpretation. Acta Biotheoretica 40 (2-3).
Rosine Chandebois (1980). Cell Sociology and the Problem of Automation in the Development of Pluricellular Animals. Acta Biotheoretica 29 (1).
Added to index2009-01-28
Total downloads6 ( #147,143 of 556,840 )
Recent downloads (6 months)0
How can I increase my downloads?