primary-cell-cultures-from-drosophila-gastrula-embryos

Primary Cell Cultures from <em>Drosophila</em> Gastrula Embryos

Here we describe a method for preparing and culturing primary cells dissociated from Drosophila gastrula embryos.   In brief, a large amount of staged ...

Secreted signaling molecules such as Wingless (Wg) and Decapentaplegic (Dpp) organize positional information along the proximodistal (PD) axis of the Drosophila wing imaginal disc. Responding cells activate different downstream targets depending on the combination and level of these signals and other factors present at the time of signal transduction. Two such factors, teashirt (tsh) and homothorax (hth), are initially co-expressed throughout the entire wing disc, but are later repressed in distal cells, permitting the subsequent elaboration of distal fates. Control of tsh and hth repression is, therefore, crucial for wing development, and plays a role in shaping and sizing the adult appendage. Although both Wg and Dpp participate in this control, their specific contributions remain unclear. In this report, we analyze tsh and hthregulation in the wing disc, and show that Wg and Dpp act independently as the primary signals for the repression of tsh and hth, respectively. In cells that receive low levels of Dpp, hth repression also requires Vestigial (Vg). Furthermore, although Dpp is required continuously for hth repression throughout development, Wg is only required for the initiation of tsh repression. Instead, the maintenance of tsh repression requires Polycomb group (PcG) mediated gene silencing, which is dispensable for hth repression. Thus, despite their overall similar expression patterns, tsh and hth repression in the wing disc is controlled by two very different mechanisms.

Differing strategies for the establishment and maintenance of teashirt and homothorax repression in the Drosophila wing.

Unterschiedliche Strategien f&#xFC;r die Errichtung und Wartung von teashirt homothorax und Repression im Drosophila-Fl&#xFC;gel.

The division of the wing imaginal disc into anterior, posterior, dorsal, and ventral compartments is a critical step in Drosophila wing morphogenesis. Here, we investigate the existence of cell lineage restrictions along the proximal-distal (PD) axis of the wing disc. We rule out the existence of classical compartment boundaries in the hinge region, but demonstrate that there are clonal restrictions corresponding to the expression domains of two transcription factors, Nubbin (Nub) and Teashirt (Tsh), present in distal and proximal cells, respectively. Unlike classical compartments, the Nub and Tsh domains do not define absolute lineage restrictions. Instead, due to regulation by Wingless signaling, the Nub and Tsh expression boundaries shift during development. Once established, the Nub and Tsh domains, and the intervening region in which neither factor is expressed, grow independently, because the progeny of cells present in one domain do not freely populate an adjacent domain. We also show that despite shifting position, the Nub and Tsh domain boundaries, like compartment boundaries, impact the expression of secreted signaling molecules. Thus, like the vein/intervein divisions of the wing and mammalian rhombomeres, the Nub and Tsh domains share some of the attributes of classical compartments, but lack their stringent and immobile boundaries.

Nubbin and Teashirt mark barriers to clonal growth along the proximal-distal axis of the Drosophila wing.

Die Aufteilung der Fl&uuml;gel so Scheibe in anterior, posterior, dorsal und ventral F&auml;cher ist ein entscheidender Schritt in Drosophila Fl&uuml;gel Morphogenese. Hier untersuchen wir Zelle Abstammung Einschr&auml;nkung entlang der proximalen und distalen (PD)-Achse der Scheibe Fl&uuml;gel der. Wir die Existenz der klassischen Fach Grenzen in der Region Scharnier ausschlie&szlig;en, aber belegen, da&szlig; klonalen Einschr&auml;nkungen entsprechend den Ausdruck-Dom&auml;nen von zwei Transkriptionsfaktoren, Nubbin (Nub) und Teashirt (Tsh), im distalen und proximalen Zellen, beziehungsweise. Im Gegensatz zu klassischen Abteilen definieren die Nub und Tsh-Dom&auml;nen nicht absolute &Uuml;bertragungslinie Einschr&auml;nkungen. Stattdessen signalisieren durch Regulierung von Wingless, die Nub und Tsh Ausdruck Grenzen Verschiebung w&auml;hrend der Entwicklung. Sobald hergestellt, wachsen die Nub und Tsh-Domains und der eingreifenden Region, in der weder Faktor ausgedr&uuml;ckt wird, unabh&auml;ngig, weil die Nachkommen von Zellen in einer Dom&auml;ne eine angrenzende Dom&auml;ne nicht frei auff&uuml;llen zu tun. Wir zeigen auch, dass trotz Verschiebung Stellung, die Nub und Tsh Anwendungsdom&auml;nengrenzen hinweg, wie Fach-Grenzen, den Ausdruck des sekretierten signalisierende Molek&uuml;le auswirken. So wie die Vene/Intervein-Divisionen der Fl&uuml;gel und S&auml;ugetier-Rhombomeres, Nub und Tsh Dom&auml;nen teilen einige der Attribute des klassischen F&auml;chern, aber ihre strengen und unbeweglichen Grenzen fehlen.

Article	Year
Differing strategies for the establishment and maintenance of teashirt and homothorax repression in the Drosophila wing. Development (Cambridge, England)\| PubMed ID: 15509768	2004
Nubbin and Teashirt mark barriers to clonal growth along the proximal-distal axis of the Drosophila wing. Developmental biology\| PubMed ID: 17313943	2007
Seminars in immunopathology\| PubMed ID: 20798940	2010

Jonathan Zirin

Biography

JoVE Journal Publications

Other Publications