bs

..Our study suggests that MAGUK proteins might play important roles during AJ remodeling in epithelial morphogenesis...

..Here we report that the Drosophila homolog of the mammalian Serum Response Factor gene (DSRF), which encodes a MADS-box containing transcriptional regulator, is expressed in the future ..

b>Serum response factor (SRF) regulates genes involved in cell proliferation, migration, cytoskeletal organization, and myogenesis...

..We show that pico and lamellipodin share the ability to activate serum response factor (SRF), a transcription factor that responds to reduced G:F-actin ratios via its co-factor Mal...

..We show that ash2 is required to sustain the activation of the intervein-promoting genes net and blistered (bs) and to repress rhomboid (rho), a component of the EGF receptor (Egfr) pathway...

..We report that this migration requires the activity of the transcriptional factor serum response factor (SRF) and its cofactor MAL-D and present evidence that nuclear accumulation of MAL-D is induced by cell ..

..Thus, ZP domain-containing proteins may have shared functions within the aECM, while also exhibiting specific interactions with the cytoskeleton...

..Taken together, these data indicate the importance of paxillin modulation of Rho family GTPases during development and identify the LIMK pathway as a critical target of paxillin-mediated Rho regulation...

..Once dpp expression is initiated, Dpp and EGFR activities in the provein maintain each other and, in cooperation, determine vein cell differentiation...

..However, this requirement can be overridden by co-misexpression of the BMP agonist Cv-2, indicating the presence of as yet unknown cues; we discuss possible candidates...

The Mal/SRF transcription factor is regulated by the level of G-actin in cells and has important roles in cell migration and other actin-dependent processes in Drosophila...

..Additional proteins binding either to the FGFRs, to Dof, or to Csw appear to be crucial for a chemotactic response...

..Cumulatively, our analysis suggests that CR domains interact physically with adjacent protein sequences to create forms of Sog with distinct BMP modulatory activities...

..can modulate gene expression, in part, by activating LIM kinase (LIMK) and consequently affecting actin-induced SRF transcriptional activity...

..A recent paper suggests that a hitherto overlooked cellular behaviour governs the size and shape of a growing tissue, and issues a challenge to developmental biologists to identify the molecular mechanisms involved...

..We propose that the attractive and repulsive tracheal responses to Slit are mediated by different combinations of Robo and Robo2 receptors on the cell surface...

..These results indicate that tracheal patterning depends not only on signalling from surrounding cells but also in the different response of the tracheal cells depending on their allocation to the dorsal or ventral domains...

..Integrins also participate in signaling events that govern tissue differentiation and organogenesis. Finally, adhesion by integrin-mediated junctions allows tissues to withstand mechanical load and is essential for tissue integrity...

..A model recapitulating the molecular interplay between the Hh, Dpp and EGF signalling pathways in the wing AP organiser is presented...

..Taken together, these studies suggest that Sog and Cv promote BMP signaling by transporting a BMP heterodimer from the longitudinal veins into the crossvein regions...

..This re-evaluation utilized different genetic testcrosses to generate heterozygous individuals with a variety of genetic backgrounds as well as sampling of new alleles from Kenyan stocks...

..These results suggest a mechanism by which Ci may activate targets such as kn, which do not have classical Ci/Gli-binding sites...

..Given the similarities in the formation of fine respiratory tubes and capillaries, we propose that an inward membrane growth model could account for lumen formation in both processes...

..Finally, we show that Rap1 acts through the effector Canoe to regulate these developmental processes...

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..We also find that salm activity is down-regulated by its own product and by that of the Pax gene eyegone...

..We also find that Cv-2 expression is controlled by BMP signaling, and these combined properties enable Cv-2 to exquisitely tune BMP signaling...

..We propose that the autonomous response to hypoxia that occurs in tracheal cells enhances tracheal sensitivity to increasing Branchless levels, and that this mechanism is a cardinal step in hypoxia-dependent tracheal sprouting...

..In summary, the involvement of Ttk in different steps of tube morphogenesis identifies it as a key player in tracheal development...

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..Other miRNAs might promote specific developmental switches during the development and regeneration of muscles...

..These results indicate that fusion cells undergo dynamic changes in gene expression as they switch from migratory to fusion modes and that dysfusion regulates a discrete, but important, set of these genes...

..This finding establishes a link between a developmental pathway governing tracheal formation and cell adhesiveness...

..Drosophila miR-1 (dmiR-1) is regulated through a serum response factor-like binding site in cardiac progenitor cells...

..Ras and the Mapk pathway are also needed for Egf-regulated cell division/survival, but Pointed is dispensable...

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The transcription factor serum response factor (SRF) regulates expression of growth factor-dependent genes and muscle-specific genes in vertebrates. Homologous factors regulate differentiation of some ectodermic tissues in invertebrates...

..We also present evidence showing that activation of the Notch signal transduction pathway is involved in triggering apoptosis of cells misspecified for their dorsal-ventral position...

..Our results support the idea that localised inactivation of transcriptional repressors such as Cic is a rather general mechanism for regulation of target gene expression by the Ras/Raf pathway...

..The inability of OUbx to function like Drosophila Ubx (DUbx) in the embryonic ectoderm indicates that the Ubx protein may have acquired new cofactors or activity modifiers since the divergence of the onychophoran and insect lineages...

The Drosophila homolog of the vertebrate serum response factor (SRF) was isolated by low stringency hybridization...

..The results show that genes of the Ras signalling pathway are co-operatively involved in the activity of emc during cell proliferation, and later antagonistically during cell differentiation, repressing EMC expression...

..Combinatorial regulation by selector proteins and signal transducers is likely to be a general feature of the tissue-specific control of gene expression during organogenesis...

..Thus several of these loci are good candidates for genes encoding cytoplasmic proteins required for integrin function...

..We present a model in which different A/P boundaries organize vein-specific genetic programs to govern the development of individual veins...

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..protein and a subset of Wg- and Decapentaplegic-activated genes such as spalt-related, vestigial, Serum Response Factor, and achaete-scute, whose products regulate morphological features that differ between the wing and ..

..blistered encodes for a nuclear protein homologous to the mammalian Serum Response Factor and is expressed in presumptive intervein cells of third larval instar and pupal wing discs...

..We propose that hdc acts non-autonomously in an inhibitory signaling mechanism to determine the number of cells that will form unicellular sprouts in the trachea...

..sprouty encodes a novel cysteine-rich protein that defines a new family of putative signaling molecules that may similarly function as FGF antagonists in vertebrate development...

..The features include cytoskeletal specializations and certain cell surface and ECM molecules...

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..Tracheal cell fate choices are determined by signaling cascades triggered by signals emanating from the tracheal cells, as well as by ligands produced by adjacent tissues...

..These activities of Wingless signaling together specify the shape of the dorsal trunk and other fusion branches...

..The expression of nemo during embryogenesis is dynamic and dsRNA inhibition and ectopic expression studies indicate that nemo is essential during embryogenesis...

..Three of these groups, Group IIa/scribbler (also known as brakeless), Group IIc/blistered, and Group IId/net, are known genes, while two appear to be novel...

..We also discuss the existence of an evolutionarily conserved pathway linking Notch signalling and COE regulatory functions in various developmental decisions...

The Drosophila serum response factor (DSRF) is expressed in the precursors of the terminal tracheal cells and in the future intervein territories of the third instar wing imaginal disc...

..Mutations in Star and l(2)43Bb had no significant effect upon the lambdatop eggshell defect whereas smt3 and dock alleles significantly suppressed the lambdatop phenotype...

..As a consequence of this constraint, cells lying in a narrow line immediately outside the signal-producing domain are the only cells that can respond to the signal by activating expression of vein-promoting genes...

..We propose that Rib is a key regulator of epithelial morphogenesis that promotes migration and morphogenesis of the tracheal cell bodies and apical surface and other morphogenetic movements...

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..More than 30 genes have been identified and ordered into sequential steps controlling branching morphogenesis. These studies have revealed a number of important principles that might be conserved in other systems...

..Moreover, the studies may enable us to trace the evolution of this gene family...

..Our results further suggest that net is required to maintain intervein development by restricting Egfr signalling, which promotes vein development, to the Net-free vein regions of the wing disc...

..These data suggest that HNT is a tissue-specific factor that regulates maintenance of the tracheal epithelium as well as differentiation of taenidia...

..Analysis of the function of dof, which encodes a cytoplasmic protein required for FGF signal transduction may provide an insight into these issues...

..Furthermore, this restricted expression depends on ERK function both in Drosophila and Xenopus, suggesting that MKP3 constitutes a conserved negative feedback loop on the activity of the Ras/ERK signaling pathway...

..Plexus may regulate transcription of vein-and intervein-specific genes by tethering transcriptional regulators to specific locations in the nucleus...

..We propose a model in which the combined activities of kni and knrl organize development of the L2 vein in the appropriate position...

..The reiterative use of a signaling pathway by both insects and mammals suggests a general scheme for patterning branching morphogenesis...

..Orthogonal expression of Hedgehog and Decapentaplegic in the epidermis instructs monopolar extension of the terminal branch along the posterior compartment, thereby matching the pattern of airway growth with that of the epidermis...

..These features strongly suggest that Crossveinless 2 acts extracelluarly or in the secretory pathway to directly potentiate Dpp or Gbb signaling...

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..Our results suggest that Vestigial specifies the cytoskeletal changes that lead to morphogenesis of the adult wing...

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..In addition, we find that a subset of planar cell polarity genes is required for the proper orientation of cell division during organ development...

..These tools will have broad applications and will lead to the discovery of novel genetic interactions in Drosophila that could not have been detected using currently available methods. ..