Genetic Control Of Morphogenesis Research Articles

The central nervous system of ascidian larvae.

Ascidians are marine invertebrate chordates. Their tadpole larvae contain a dorsal tubular nervous system, resulting from the rolling up of a neural plate. Along the anterior-posterior (A-P) axis, the central nervous system (CNS) is organized into a sensory vesicle, neck, trunk ganglion, and tail nerve cord and consists of approximately only 330 cells, of which around 100 are thought to be neurons. The organization of distinct neuronal cell types and neurotransmitter gene expression within the CNS has been described. The unique developmental mode of ascidians, with a small number of cells and a fixed cell division pattern, allows individual cells to be traced throughout development. This feature has led to the complete documentation of the cell lineages of certain cell types in the CNS. Thus, a step-by-step understanding of nervous system development from the initial stages of neural induction to the neurogenesis of individual neurons is a feasible goal. The genetic control of neural fate induction and early neural plate patterning are now well understood. The molecular mechanisms specifying the cholinergic neurons of the trunk ganglion as well as the pigment cells of the sensory organs are also well elucidated. In addition, studies have begun on the morphogenetic processes of neurulation. Remaining challenges include building an embryonic atlas integrating gene expression patterns, cell lineage, and neuronal cell types as well as developing the gene regulatory networks of cell fate specification and integrating them with the genetic control of morphogenesis. WIREs Dev Biol 2016, 5:538-561. doi: 10.1002/wdev.239 For further resources related to this article, please visit the WIREs website.

Pattern Recognition and Gestalt Psychology: The Day Nüsslein‐Volhard Shouted “Toll!”

Pattern Recognition and Gestalt Psychology: The Day Nüsslein‐Volhard Shouted “Toll!”

Environmental and genetic control of morphogenesis in crops: towards models simulating phenotypic plasticity

As molecular biologists are realising the importance of physiology in understanding functional genomics of quantitative traits, and as physiologists are realising the formidable prospects for improving their phenotypic models with information on the underlying gene networks, researchers worldwide are working on linked physiological–genetic models. These efforts are in their early methodological stage despite, or because of, the availability of many different types of models, the problem being to bring together the different ways that scientists see the plant. This paper describes some current efforts to adapt phenotype models to the objective of simulating gene-phene processes at the plant or crop scale. Particular emphasis is given to the models’ capacity to simulate genotype × environment interaction and the resulting phenotypic plasticity, assuming that this permits the defining of model parameters that are closer to specific gene action. Three different types of approaches are presented: (1) a generic, mathematical-architectural model called GREENLAB that simulates resource-modulated morphogenesis; (2) an ecophysiological model of peach tree fruit development and filling, parameterised for a mapping population to evaluate the potential of plugging quantitative trait locus (QTL) effects into the model; and (3) the new model Ecomeristem that constructs plant architecture and its phenotypic plasticity from meristem behaviour, the principal hypothesis being that resource limitations and stresses feed back on the meristems. This latter choice is based on the fact that gene expression happens to a large extent in the meristems. The model is evaluated on the basis of preliminary studies on vegetative-stage rice. The different modelling concepts are critically discussed with respect to their ability to simulate phenotypic plasticity and to operate with parameters that approximate specific gene action, particularly in the area of morphogenesis.

Announcements

Anatomical Society of Great Britain and Ireland Winter meeting, 5–7 January 1999. This will be held at the University of Leeds and will include a one and a half day symposium on ‘Structure and function of molecular motors’. Further information can be obtained from Dr Roger Soames, Centre for Human Biology, University of Leeds, Leeds LS2 9JT. Summer meeting, 24–26 July 2000. This will be held at the University of Cambridge. European Research Conference Neural Mechanisms of Learning and Memory: Dynamics of the Trace. To be held in Acquafredda di Maratea, Italy, 9–14 May 1998.Development Biology: The Genetic Control of Morphogenesis. To be held in Lengries, Germany, 6–11 June 1998.Details may be obtained from Dr J. Hendekovic, URESCO Unit, European Science Foundation, 1 quai Lezay‐Marnésia, 67080 Strasbourd Cedex, France. Tel. +33 388 76163; fax +33 388 366987; e‐mail euresco@esf.org. Online information and application at: http//www.esforg/euresco

Announcements

Journal of AnatomyVolume 193, Issue 1 p. 159-159 Free Access Announcements First published: 17 December 2002 https://doi.org/10.1046/j.1469-7580.1998.19310159.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract Anatomical Society of Great Britain and Ireland Winter meeting, 5–7 January 1999. This will be held at the University of Leeds and will include a one and a half day symposium on ‘Structure and function of molecular motors’. Further information can be obtained from Dr Roger Soames, Centre for Human Biology, University of Leeds, Leeds LS2 9JT. Summer meeting, 24–26 July 2000. This will be held at the University of Cambridge. European Research Conference Neural Mechanisms of Learning and Memory: Dynamics of the Trace. To be held in Acquafredda di Maratea, Italy, 9–14 May 1998. Development Biology: The Genetic Control of Morphogenesis. To be held in Lengries, Germany, 6–11 June 1998. Details may be obtained from Dr J. Hendekovic, URESCO Unit, European Science Foundation, 1 quai Lezay-Marnésia, 67080 Strasbourd Cedex, France. Tel. +33 388 76163; fax +33 388 366987; e-mail euresco@esf.org. Online information and application at: http//www.esforg/euresco Volume193, Issue1July 1998Pages 159-159 RelatedInformation

Anatomical Society of Great Britain 24–26 July, 2000. University of Cambridge. European Research Conference Development Biology: The Genetic Control of Morphogenesis. To be held in Lengries, Germany, 6–11 June 1998.

<i>Anatomical Society of Great Britain 24–26 July, 2000</i>. University of Cambridge. <i>European Research Conference</i> Development Biology: The Genetic Control of Morphogenesis. To be held in Lengries, Germany, 6–11 June 1998.

Announcements

Anatomical Society of Great Britain 15–18 April, 1998. Joint meeting with the Nederlandse Anatomen Vereniging in Rolduc, Netherlands, in cooperation with the South African Anatomical society. 24–26 July, 2000. University of Cambridge. European Research Conference Biophysics of the Cytoskeleton. To be held in Obernai, near Strasbourg, France, 22–27 April 1998Neural Mechanisms of Learning and Memory: Dynamics of the Trace. To be held in Acquafredda di Maratea, Italy, 9–14 May 1998.Development Biology: The Genetic Control of Morphogenesis. To be held in Lengries, Germany, 6–11 June 1998.

GRISEA, a putative copper-activated transcription factor from Podospora anserina involved in differentiation and senescence.

Podospora anserina is a filamentous fungus with a limited lifespan. Lifespan is controlled by both environmental and genetic factors. Using a combination of genetic and molecular approaches we have cloned one of these factors, gerontogene grisea. The cloned wild-type copy of grisea complements the altered morphological characteristics (e.g., colony and ascospore color), the defect in gametangia development, and the increased lifespan of the pleiotropic mutant grisea. A molecular analysis revealed that grisea is a discontinuous gene with a single intron. The deduced amino acid sequence shows significant homology to MAC1, ACE1 and AMT1, indicating that GRISEA, like the proteins from Saccharomyces cerevisiae (MAC1 and ACE1) and Candida glabrata (AMT1), codes for a copper-activated transcription factor. This conclusion is consistent with the pleiotropic nature of the grisea phenotype. We suggest that the gerontoprotein GRISEA is one component of a transcription apparatus involved in the genetic control of morphogenesis and aging.

Arabidopsis thaliana: a Model Plant for Studying the Molecular Basis of Morphogenesis

Morphogenesis in higher plants is likely to be controlled by the serial activation of genes. These genes could be identified if the structure which they normally control is specifically disrupted when they are in mutant form. By cloning and characterising the products of such genes we could gain an understanding of the genetic control of morphogenesis. This report makes a case for following this strategy using Arabidopsis thaliana as a model species. This species is easily grown, has a short, 6-week life cycle and convenient genetics. Mutations affecting embryogenesis, trichome structure, the inflorescence and floral organs are already known. Because Arabidopsis has a tiny genome (70 000 kbp), cloning of genes known only by mutant phenotype is practicable by chromosome walking and DNA tagging. The role of their products in cellular and developmental decisions could then be investigated. Genes controlling morphogenesis are likely to be conserved across higher plants. Once they have been cloned from a model species their isolation from other species by DNA hybridisation is relatively simple. Generalisations about the origin, action and evolution of such genes would then be possible. Also artificial manipulation of morphogenesis may be achievable.

Genetic control of morphogenesis in the multicellular alga Ulva mutabilis: Defect in cell wall production

Distinct ultrastructural differences between the cell walls of the mutant lumpy (lu) and wild-type are demonstrated. The polyglucan fibrils in the wild-type wall appear straight and densely packed compared to the more uneven and loosely woven fibrils in the mutant wall. The mutant grows as an aggregate of loosely connected cells. The three cell types seen in the wild type do not differentiate, and consequently no blade and holdfast forms. It is suggested that the defect in the cell wall production takes away a necessary condition for normal morphogenesis. The lumpy mutant shows epistasis over two other chromosomal mutants, bu and Sl, described earlier to be morphogenic.