... is still hotly contested, with multiple models proposed for different systems. Here, we focus on the transcription factor Bicoid (Bcd), a morphogen that forms an exponential gradient across the anterior-posterior (AP) axis of the early Drosophila embryo. Using fluorescence correlation spectroscopy we find...

... a set of principles for morphogen-patterned tissues. Bicoid Drosophila blastoderm Gene regulatory network Morphogen interpretation Sonic hedgehog Vertebrate neural tube The importance of gradients in developing embryos and regenerating tissue has long been recognized. From initial...

... their precise timing may impact embryonic development. Here we perturb the timing of the shutdown of Bicoid (Bcd)-dependent hunchback ( hb ) transcription in the embryo through the use of a Bcd mutant that has heightened activating potency. A delayed shutdown specifically increases Bcd-activated hb levels...

... network in Drosophila melanogaster embryos by depleting a key maternal input, bicoid ( bcd ), and measuring gene expression patterns of the network at cellular resolution. This method results in a gene expression atlas containing the levels of mRNA or protein expression of 13 core patterning genes over...

... interrogations of the properties of morphogen gradients that instruct patterning. Recent studies of the Drosophila morphogen gradient Bicoid (Bcd), which is required for anterior-posterior (AP) patterning in the early embryo, have uncovered two distinct ways of scaling. Whereas between-species scaling...

.... For morphogens that function as transcription factors, the final distribution can be heavily influenced by the number of nuclear binding sites. Here, we have addressed the role of the increasing number of nuclei during the formation of the Bicoid gradient in embryos of Drosophila melanogaster . Deletion...

...Oliver Grimm; Mathieu Coppey; Eric Wieschaus Morphogen gradients provide embryonic tissues with positional information by inducing target genes at different concentration thresholds and thus at different positions. The Bicoid morphogen gradient in Drosophila melanogaster embryos has recently been...

...Kay Kotkamp; Martin Klingler; Michael Schoppmeier In the short-germ beetle Tribolium castaneum , the head gap gene orthodenticle ( Tc-otd ) has been proposed to functionally substitute for bicoid , the anterior morphogen unique to higher dipterans. In this study we reanalyzed the function of Tc-otd...

... activation in Drosophila , we used loss- and gain-of-function experiments in the hover fly Episyrphus balteatus (Syrphidae) to address the question of how the maternal regulation of gap genes evolved. We find that, in Episyrphus , a highly diverged bicoid ortholog is solely responsible for the AP polarity...

...Timothy T. Weil; Despina Xanthakis; Richard Parton; Ian Dobbie; Catherine Rabouille; Elizabeth R. Gavis; Ilan Davis Localization of bicoid mRNA to the anterior of the Drosophila oocyte is essential for patterning the anteroposterior body axis in the early embryo. bicoid mRNA localizes in a complex...

...Alexander Spirov; Khalid Fahmy; Martina Schneider; Erich Frei; Markus Noll; Stefan Baumgartner The Bicoid (Bcd) protein gradient is generally believed to be established in pre-blastoderm Drosophila embryos by the diffusion of Bcd protein after translation of maternal mRNA, which serves...

... the issue of whether such differences co-evolve with the mechanisms that establish anteroposterior (AP) polarity of the embryo. AP polarity of the Drosophila embryo depends on bicoid , which is necessary and sufficient to determine the anterior body plan. Orthologs of bicoid have been identified in various...

... unknown. In many developmental mutants in Drosophila , large numbers of mis-specified cells die synchronously, providing a convenient model for analysis of this phenomenon. The maternal mutant bicoid is particularly useful model with which to address this issue because its mutant phenotype...

...Veit Riechmann; Anne Ephrussi The Ser/Thr kinase Par-1 is required for cell polarisation in diverse organisms such as yeast, worms, flies and mammals. During Drosophila oogenesis, Par-1 is required for several polarisation events, including localisation of the anterior determinant bicoid...

...Sophie G. Martin; Vincent Leclerc; Katie Smith-Litière; Daniel St Johnston The anteroposterior axis of Drosophila is defined during oogenesis, when the polarisation of the oocyte microtubule cytoskeleton directs the localisation of bicoid and oskar mRNAs to the anterior and posterior poles...

...Chen Zhao; Allen York; Fan Yang; David J. Forsthoefel; Vrushank Dave; Dechen Fu; Dongyi Zhang; Maria S. Corado; Stephen Small; Mark A. Seeger; Jun Ma The Drosophila morphogenetic protein Bicoid (Bcd) is a homeodomain-containing activator that stimulates the expression of target genes during early...

... the control of the AP patterning system and require bicoid activity. The anterior-most domain is a region of large yolk stalk diameters and corresponds to the region of decreased nuclear densities observed during syncytial stages. The middle domain shows smaller yolk stalk diameters and more rapid...

... cells is due to overproliferation, we counted the number of cells using three-dimensional microscopy and found a twofold increase in the number of posterior follicle cells, but no changes in other follicle cells (data not shown). Drosophila oogenesis Merlin gurken bicoid oskar TGFα...

...Valérie Schaeffer; Darrell Killian; Claude Desplan; Ernst A. Wimmer ABSTRACT In Drosophila , the gradient of the Bicoid (Bcd) morphogen organizes the anteroposterior axis while the ends of the embryo are patterned by the maternal terminal system. At the posterior pole, expression of terminal gap...

...Qian Gao; Robert Finkelstein ABSTRACT The Bicoid (Bcd) morphogen establishes the head and thorax of the Drosophila embryo. Bcd activates the transcription of identified target genes in the thoracic segments, but its mechanism of action in the head remains poorly understood. It has been proposed...