Morphogen gradient interpretation

Gurdon, J. B.; Bourillot, Pierre‐Yves

doi:10.1038/35101500

Cited by 687 publications

(501 citation statements)

References 49 publications

Supporting

Mentioning

491

Contrasting

Unclassified

Order By: Relevance

“…In practice, of course, threshold responses are common Gurdon and Bourillot, 2001). To give distinct cell types, morphogen interpretation relies on the sharpness of threshold responses to cellular stimuli.…”

Section: Interpretation Of Gradients Part I: Threshold Responses Andmentioning

confidence: 99%

“…As has emerged over the past 15 years of developmental biology, embryos of diverse species do in fact use morphogen gradients repeatedly in the development of the individual embryo. There have been several reviews that provide an overview of known morphogen gradients, especially in Drosophila development (Lawrence and Struhl, 1996;Dale, 1997;Strigini and Cohen, 1999;Tickle, 1999;Podos and Ferguson, 1999;Day and Lawrence, 2000;Tabata, 2001;Gurdon and Bourillot, 2001;Lawrence, 2001a). This review will focus on morphogen gradients in vertebrates with an emphasis on how studies using Xenopus have provided insight into both the existence of morphogens and their detailed mechanisms of action.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Morphogen gradients, positional information, and Xenopus: Interplay of theory and experiment

Green

2002

Developmental Dynamics

View full text Add to dashboard Cite

The idea of morphogen gradients has long been an important one in developmental biology. Studies with amphibians and with Xenopus in particular have made significant contributions to demonstrating the existence, identity, and mechanisms of action of morphogens. Mesoderm induction and patterning by activin, nodals, bone morphogenetic proteins, and fibroblast growth factors have been analyzed thoroughly and reveal recurrent and combinatorial roles for these protein growth factor morphogens and their antagonists. The dynamics of nodal-type signaling and the intersection of VegT and ␤-catenin intracellular gradients reveal detailed steps in early long-range patterning. Interpretation of gradients requires sophisticated mechanisms for sharpening thresholds, and the activin-Xbra-Gsc system provides an example of this. The understanding of growth factor signal transduction has elucidated growth factor morphogen action and provided tools for dissecting their direct longrange action and distribution. The physical mechanisms of morphogen gradient establishment are the focus of new interest at both the experimental and theoretical level. General themes and emerging trends in morphogen gradient studies are discussed.

show abstract

Section: Interpretation Of Gradients Part I: Threshold Responses Andmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Morphogen gradients, positional information, and Xenopus: Interplay of theory and experiment

Green

2002

Developmental Dynamics

View full text Add to dashboard Cite

show abstract

“…Many of these same factors are involved in neuronal plasticity in the postnatal brain (Fagiolini et al, 2003;Iwasato et al, 2000). Indeed, it has been proposed that tissue formation and polarity may be determined largely by a gradient for a signal antagonist, such as kynurenic acid, rather than an agonist (Gurdon and Bourillot, 2001). …”

mentioning

confidence: 99%

Prenatal inhibition of the tryptophan–kynurenine pathway alters synaptic plasticity and protein expression in the rat hippocampus

et al. 2013

View full text Add to dashboard Cite

Glutamate receptors sensitive to N-methyl-D-aspartate (NMDA) are important in early brain development, influencing cell proliferation and migration, neuritogenesis, axon guidance and synapse formation. The kynurenine pathway of tryptophan metabolism includes an agonist (quinolinic acid) and an antagonist (kynurenic acid) at these receptors.Rats were treated in late gestation with 3,4-dimethoxy-N-[4-(3-nitrophenyl)thiazol-2-yl]-benzene-sulphonamide (Ro61-8048), an inhibitor of kynurenine-3-monoxygenase which diverts kynurenine metabolism to kynurenic acid. Within 5h of drug administration there was a significant decrease in GluN2A expression and increased GluN2B in the embryo brains, with changes in sonic hedgehog at 24h. When injected dams were allowed to litter normally, the brains of offspring were removed at postnatal day 21 (P21). Recordings of hippocampal field excitatory synaptic potentials (fEPSPs) showed that prenatal exposure to Ro61-8048 increased neuronal excitability and paired-pulse facilitation. Long-term potentiation was also increased, with no change in long-term depression. At this time, levels of GluN2A, GluN2B and postsynaptic density protein PSD-95 were all increased.Among several neurodevelopmental proteins, the expression of sonic hedgehog was increased, but DISC1 and dependence receptors were unaffected, while raised levels of doublecortin and Proliferating Cell Nuclear Antigen (PCNA) suggested increased neurogenesis. The results reveal that inhibiting the kynurenine pathway in utero leads to molecular and functional synaptic changes in the embryos and offspring, indicating that the pathway is active during gestation and plays a significant role in the normal early development of the embryonic and neonatal nervous system. 3

show abstract

“…In terms of (τ), (12) takes the form, (16) So the new r-th order implicit schemes are (17) where α 1 , α 0 , α −1 ,···, α −r+2 are coefficients calculated from the integrals of the polynomial in (τ), (18) In Table 2, the value of coefficients, α −j , for schemes of order up to four are listed.…”

Section: Two-dimensionsmentioning

confidence: 99%

“…Morphogens are signaling molecules that, when bound to cell receptors, assign different cell fates at different concentrations [15,16]. This role of morphogens has been the prevailing thought in tissue patterning for over half a century; but only recently have there been sufficient experimental data and adequate modeling for us to begin to understand how various morphogens interact and patterns emerge [17][18][19].…”

Section: A Two-dimensional Model For Dorsal-ventral Patterning-formentioning

confidence: 99%

Compact integration factor methods in high spatial dimensions

Nie

Wan

Zhang

et al. 2008

Journal of Computational Physics

View full text Add to dashboard Cite

The dominant cost for integration factor (IF) or exponential time differencing (ETD) methods is the repeated vector-matrix multiplications involving exponentials of discretization matrices of differential operators. Although the discretization matrices usually are sparse, their exponentials are not, unless the discretization matrices are diagonal. For example, a two-dimensional system of N × N spatial points, the exponential matrix is of a size of N 2 × N 2 based on direct representations. The vector-matrix multiplication is of O(N 4 ), and the storage of such matrix is usually prohibitive even for a moderate size N. In this paper, we introduce a compact representation of the discretized differential operators for the IF and ETD methods in both two-and three-dimensions. In this approach, the storage and CPU cost are significantly reduced for both IF and ETD methods such that the use of this type of methods becomes possible and attractive for two-or three-dimensional systems. For the case of two-dimensional systems, the required storage and CPU cost are reduced to O(N 2 ) and O(N 3 ), respectively. The improvement on three-dimensional systems is even more significant. We analyze and apply this technique to a class of semi-implicit integration factor method recently developed for stiff reaction-diffusion equations. Direct simulations on test equations along with applications to a morphogen system in two-dimensions and an intra-cellular signaling system in three-dimensions demonstrate an excellent efficiency of the new approach.

show abstract

Morphogen gradient interpretation

Cited by 687 publications

References 49 publications

Morphogen gradients, positional information, and Xenopus: Interplay of theory and experiment

Morphogen gradients, positional information, and Xenopus: Interplay of theory and experiment

Prenatal inhibition of the tryptophan–kynurenine pathway alters synaptic plasticity and protein expression in the rat hippocampus

Compact integration factor methods in high spatial dimensions

Contact Info

Product

Resources

About