The transcription factor Zfh1 is involved in the regulation of neuropeptide expression and growth of larval neuromuscular junctions in Drosophila melanogaster.

Different aspects of neural development are tightly regulated and the underlying mechanisms have to be transcriptionally well controlled. Here we present evidence that the transcription factor Zfh1, the Drosophila member of the conserved zfh1 gene family, is important for different steps of neuronal differentiation. First, we show that late larval expression of the neuropeptide FMRFamide is dependent on correct levels of Zfh1 and that this regulation is presumably direct via a conserved zfh1 homeodomain binding site in the FMRFamide enhancer.

Connecting temporal identity to mitosis: the regulation of Hunchback in Drosophila neuroblast lineages.

Both in vertebrates and invertebrates, neural stem cells generate different cell types at different times during development. It has been suggested that this process depends on temporal identity transitions of neural progenitors, but the underlying mechanism has not been resolved, yet. Recently, Drosophila neuroblasts (NBs) have been shown to be an excellent model system to investigate this subject.

Timing of identity: spatiotemporal regulation of hunchback in neuroblast lineages of Drosophila by Seven-up and Prospero.

Neural stem cells often generate different cell types in a fixed birth order as a result of temporal specification of the progenitors. In Drosophila, the first temporal identity of most neural stem cells (neuroblasts) in the embryonic ventral nerve cord is specified by the transient expression of the transcription factor Hunchback. When reaching the next temporal identity, this expression is switched off in the neuroblasts by seven up (svp) in a mitosis-dependent manner, but is maintained in their progeny (ganglion mother cells).

Retrieval of vertical constituents and temperature profiles from passive submillimeter wave limb observations of the Martian atmosphere: a feasibility study.

The investigation of the Martian atmosphere is of key importance for an understanding of the planets present and past. Passive limb observations of thermal radiation at submillimeter wavelengths in the 320-350-GHz range by use of a state-of-the-art satellite receiver on a low Mars orbit allow important parameters such as the mixing ratios of H2O, HDO, 12CO, 13CO, O3, and H2O2 as well as the thermal profile to be retrieved with high precision and unprecedented vertical range and resolution, providing valuable information for better understanding of the planet's water cycle, atmospheric dynamics, and photochemistry. The feasibility of these kinds of measurement is demonstrated by means of model simulations based on realistic atmospheric, spectroscopic, and instrumental parameters.

The ladybird homeobox genes are essential for the specification of a subpopulation of neural cells.

In Drosophila, neurons and glial cells are produced by neural precursor cells called neuroblasts (NBs), which can be individually identified. Each NB generates a characteristic cell lineage specified by a precise spatiotemporal control of gene expression within the NB and its progeny. Here we show that the homeobox genes ladybird early and ladybird late are expressed in subsets of cells deriving from neuroblasts NB 5-3 and NB 5-6 and are essential for their correct development.

Charting the Drosophila neuropile: a strategy for the standardised characterisation of genetically amenable neurites.

Insect neurons are individually identifiable and have been used successfully to study principles of the formation and function of neuronal circuits. In the fruitfly Drosophila, studies on identifiable neurons can be combined with efficient genetic approaches. However, to capitalise on this potential for studies of circuit formation in the CNS of Drosophila embryos or larvae, we need to identify pre- and postsynaptic elements of such circuits and describe the neuropilar territories they occupy.

Evidence for differential and redundant function of the Sox genes Dichaete and SoxN during CNS development in Drosophila.

Group B Sox-domain proteins encompass a class of conserved DNA-binding proteins expressed from the earliest stages of metazoan CNS development. In all higher organisms studied to date, related Group B Sox proteins are co-expressed in the developing CNS; in vertebrates there are three (Sox1, Sox2 and Sox3) and in Drosophila there are two (SoxNeuro and Dichaete). It has been suggested there may be a degree of functional redundancy in Sox function during CNS development.

Characterization of Drosophila hemoglobin. Evidence for hemoglobin-mediated respiration in insects.

In contrast to previous assumptions, the fruit fly Drosophila melanogaster possesses hemoglobin. This respiratory protein forms a monomer of about 17 kDa that is not exported into the hemolymph. Recombinant Drosophila hemoglobin displays a typical hexacoordinated deoxy spectrum and binds oxygen with an affinity of 0.

Hunchback is required for the specification of the early sublineage of neuroblast 7-3 in the Drosophila central nervous system.

The Drosophila ventral nerve cord (VNC) derives from neuroblasts (NBs), which mostly divide in a stem cell mode and give rise to defined NB lineages characterized by specific sets of sequentially generated neurons and/or glia cells. To understand how different cell types are generated within a NB lineage, we have focused on the NB7-3 lineage as a model system. This NB gives rise to four individually identifiable neurons and we show that these cells are generated from three different ganglion mother cells (GMCs).

Distribution, classification, and development ofDrosophila glial cells in the late embryonic and early larval ventral nerve cord.

To facilitate the investigation of glial development inDrosophila, we present a detailed description of theDrosophila glial cells in the ventral nerve cord. A GAL4 enhancer-trap screen for glial-specific expression was performed. Using UAS-lacZ and UAS-kinesin-lacZ as reporter constructs, we describe the distribution and morphology of the identified glial cells in the fully differentiated ventral nerve cord of first-instar larvae just after hatching.