Dpp, a TGFbeta, organizes pattern in the Drosophila wing by acting as graded morphogen, activating different targets above distinct threshold concentrations. Like other TGFbetas, Dpp appears to induce transcription directly via activation of SMAD, Mad. However, here we demonstrate that can also control gene expression indirectly downregulating brinker gene, which encodes putative factor functions repress targets. The medial-to-lateral gradient along anterior-posterior axis is complemented...

ABSTRACT We report the identification of RK2, a glial-specific home-odomain protein. RK2 is localized to nucleus virtually all embryonic and imaginal glial cells, with exception midline glia. Embryos mutant for gene encoding are lethal but normal early gliogenesis (birth, initial divisions migration glia) axonogenesis (neuronal pathfinding fasciculation). However, later in development, there significantly fewer longitudinal glia that spatially disorganized; addition, slight disorganization...

In the leg and wing imaginal discs of Drosophila, expression domains homeobox genes aristaless (al) Distal-less (Dll) are defined by secreted signaling molecules Wingless (Wg) Decapentaplegic (Dpp). Here, roles played al Dll in patterning legs wings have been investigated through loss function studies. developing leg, is expressed at presumptive tip a molecularly null allele reveals that its only appears to be direct growth differentiation structures tip. contrast, has previously shown...

Cell fate decisions in the early Drosophila wing disc assign cells to compartments (anterior or posterior and dorsal ventral) distinguish future from body wall (notum). Here we show that EGF-receptor (EGFR) signaling stimulated by its ligand, Vein, has a fundamental role regulating two of these cell choices: (1) Vn/EGFR directs become notum antagonizing development activating notum-specifying genes; (2) part compartment induction apterous , selector gene, consequently also controls...

Patterning along developing body axes is regulated by gradients of transcription factors, which activate or repress different genes above distinct thresholds. Understanding differential threshold responses requires knowledge how these factors regulate transcription. In the Drosophila wing, expression such as omb and sal anteroposterior axis restricted lateral-to-medial transcriptional repressor Brinker (Brk). less sensitive to repression Brk than consequently expressed more laterally....

ABSTRACT A monoclonal antibody that recognizes the product of segmental gene, engrailed (en), Drosophila has been used to analyse expression homologous gene Oncopeltus. in abdominal segment larval Oncopeltus is confined a narrow band epidermal cells localized immediately anterior border. Expression varies intensity dur-ing postembryonic development: no detectable newly moulted larvae, but reappears soon after initiation intermoult activities. One possible function en this system revealed by...

In eukaryotes, the ability of DNA-binding proteins to act as transcriptional repressors often requires that they recruit accessory proteins, known corepressors, which provide activity responsible for silencing transcription. Several these factors have been identified, including Groucho (Gro) and Atrophin (Atro) in Drosophila. Here we demonstrate strong genetic interactions between gro Atro also with mutations a third gene, scribbler (sbb), encodes nuclear protein unknown function. We show...

Transcriptional repressors function primarily by recruiting co-repressors, which are accessory proteins that antagonize transcription modifying chromatin structure. Although a repressor could just single co-repressor, many can recruit more than one, with Drosophila Brinker (Brk) the co-repressors CtBP and Groucho (Gro), in addition to possessing third repression domain, 3R. Previous studies indicated Gro is sufficient for Brk repress targets wing, questioning why it should need CtBP,...

Members of the Hedgehog (HH) family secreted signaling molecules specify cell fate during animal development by controlling activity members Gli zinc-finger transcription factors in responding cells. In Drosophila homolog, cubitus interruptus (CI), is expressed only anterior compartment where it represses targets such as molecule genes decapentaplegic (dpp) and wingless (wg). HH posterior diffuses into antagonizes CI repression resulting dpp wg expression immediately to border. Reducing...

ABSTRACT The confrontation of cells from the anterior region an abdominal segment Oncopeltus with those posterior same or adjacent results in generation a border. behaviour epidermal during this regulation is described. It consists primarily cell division and transverse elongation at site confrontation. This can be separated any associated purely wound healing because similar-sized to that used ablate border, performed within segment, does not result elongation. are consistent view there...

ABSTRACT Cells from different levels in the anteroposterior axis of an abdominal segment Oncopeltus were confronted by scraping away strip epidermis that separated these levels. The cells migrate over wound and meet centre. subsequent behaviour epidermal was followed preparing whole mounts integument at various times after confrontation. These operations may lead to cell division alteration shape confrontation site. intensity induced pattern depends on which are evidence suggests it is...

At the 49th Annual Drosophila Research Conference from April 3-8, 2008 in San Diego there were eight talks and over ninety posters section on Organogenesis Gametogenesis. These covered a wide range of topics within two broad categories organ-specific stem cells (including germ cells) developmental programs. Here we discuss eleven these presentations describing current research into formation gonad, intestine, trachea, muscle leg joint. The new insights presented advance our understanding...