TGF-beta-related signaling pathways play diverse roles during vertebrate and invertebrate development. A common mechanism for regulating the activity of TGF-beta family members is inhibition by extracellular antagonists. Recently, the Drosophila short gastrulation (sog) gene was shown to encode a predicted diffusible factor which antagonizes signaling mediated by the TGF-beta-like Decapentapleg...

Pattern formation in the dorsal region of the Drosophila embryo depends on the activity of a small group of zygotically acting genes. dpp, a key gene in this group, encodes a TGF-beta-like product (Dpp) that has been proposed to function as a morphogen with peak levels of Dpp-specifying amnioserosa, the dorsal-most cell type, and lower Dpp levels specifying dorsal ectoderm. The short gastrulati...

We propose a novel and highly sensitive integrated read-out scheme, capable of detecting sub-nanometre deflections of a cantilever in close proximity to a grated waveguide structure. A very compact and stable sensor element can be realized by monolithically integrating a microcantilever structure with the grated waveguide (GWG), using conventional layer deposition and sacrificial layer etching ...

Sacrificial etching is one of the most important process steps in micro-electro-mechanical systems technology, since it enables the generation of free-standing structures. These structures are often the main part of micro-mechanical devices, intended to sense or induce a mechanical movement. The etching process transforms an initial multi-segmented geometry and depends on material properties an...

During early Drosophila embryogenesis, several zygotic gene products act to establish a posttranscriptional activity gradient of the morphogen DPP. Among these molecules, Tolloid, a putative metalloprotease related to BMP-1, enhances DPP function, while SOG, an ortholog of the Xenopus organizer Chordin, inhibits DPP function. Using epistasis tests and a Xenopus secondary axis induction assay, w...

The Spemann organizer has long been recognized as a major source of patterning signals during the gastrula stage of amphibian embryogenesis. More recent evidence has suggested that the ventral side of the embryo also plays an important role in dorsal-ventral patterning during gastrulation through the action of signaling factors such as BMP-4. Bmp-4 is closely related to the Drosophila decapenta...

We describe here soft nanofabrication methods using spin-on glass (SOG) materials for the fabrication of both bulk materials and replica masters. The precision of soft nanofabrication using SOG is tested using features on size scales ranging from 0.6 nm to 1.0 μm. The performance of the embossed optics is tested quantitatively via replica patterning of new classes of plasmonic crystals formed b...