The homeotic gene fork head encodes a nuclear protein and is expressed in the terminal regions of the Drosophila embryo

AbstractThe region-specific homeotic gene fork head (fkh) promotes terminal as opposed to segmental development in the Drosophila embryo. We have cloned the fkh region by chromosomal walking. P element-mediated germ-line transformation and sequence comparison of wild-type and mutant alleles identify the fkh gene within the cloned region. fkh is expressed in the early embryo in the two terminal domains that are homeotically transformed in fkh mutant embryos. The nuclear localization of the fkh protein suggests that fkh regulates the transcription of other, subordinate, genes. The fkh gene product, however, does not contain a known protein motif, such as the homeodomain or the zinc fingers, nor is it similar in sequence to any other known protein

Evaluation der Experimentierklausel nach § 6c SGB II - Untersuchungsfeld 4: Makroanalyse und regionale Vergleiche: Zwischenbericht 2007

"Im Rahmen der Evaluation der Experimentierklausel nach Paragraph 6c SGB II umfasst die Aufgabenstellung des Forschungsfeldes 4 - Makroanalyse und regionale Vergleiche - eine Analyse der regionalen Wirkungen von ARGEn und zkT (zugelassene kommunale Träger), die Analyse der gesamtwirtschaftlichen Wirkungen und ein Performancevergleich der Regionen. Insbesondere im Rahmen der Makroanalyse gilt es die Frage zu beantworten, 'Was wäre geschehen, wenn zum 1. 1. 2005 deutschlandweit entweder das ARGE-Modell oder die kommunale Trägerschaft eingeführt worden wäre?' und zwar unter besonderer Berücksichtigung regionaler Besonderheiten und Verflechtungen, sowie Substitutions-, Verdrängungs- und Mitnahmeeffekten. Bei einem Vergleich der ARGEn mit den zkT muss berücksichtigt werden, ob sich Kreise mit spezifischen Merkmalen für die eine oder die andere Form der Aufgabenwahrnehmung entschieden haben. Auf Grundlage der Vorarbeiten des Paragraph 6c-Forschungsverbundes dürften folgende Faktoren die Optionsneigung beeinflusst haben: Lokale Arbeitsmarktlage, Größe der Kommune, Finanzkraft, Sozio-geographische Merkmale, Politische Merkmale und Vorerfahrungen. Die regionalen Vergleiche dienen der Darstellung und der deskriptiven Beschreibung der Entwicklung zentraler Indikatoren für die Zielgrößen 'Integration in Erwerbstätigkeit', 'Verbesserung der Beschäftigungsfähigkeit' und 'soziale Stabilisierung' im Vergleich der drei Formen der Aufgabenwahrnehmung sowie der unterschiedlichen Organisationstypen." (Autorenreferat

Dual Lipolytic Control of Body Fat Storage and Mobilization in Drosophila

Energy homeostasis is a fundamental property of animal life, providing a genetically fixed balance between fat storage and mobilization. The importance of body fat regulation is emphasized by dysfunctions resulting in obesity and lipodystrophy in humans. Packaging of storage fat in intracellular lipid droplets, and the various molecules and mechanisms guiding storage-fat mobilization, are conserved between mammals and insects. We generated a Drosophila mutant lacking the receptor (AKHR) of the adipokinetic hormone signaling pathway, an insect lipolytic pathway related to ß-adrenergic signaling in mammals. Combined genetic, physiological, and biochemical analyses provide in vivo evidence that AKHR is as important for chronic accumulation and acute mobilization of storage fat as is the Brummer lipase, the homolog of mammalian adipose triglyceride lipase (ATGL). Simultaneous loss of Brummer and AKHR causes extreme obesity and blocks acute storage-fat mobilization in flies. Our data demonstrate that storage-fat mobilization in the fly is coordinated by two lipocatabolic systems, which are essential to adjust normal body fat content and ensure lifelong fat-storage homeostasis

Gain-of-function screen for genes that affect Drosophila muscle pattern formation.

This article reports the production of an EP-element insertion library with more than 3,700 unique target sites within the Drosophila melanogaster genome and its use to systematically identify genes that affect embryonic muscle pattern formation. We designed a UAS/GAL4 system to drive GAL4-responsive expression of the EP-targeted genes in developing apodeme cells to which migrating myotubes finally attach and in an intrasegmental pattern of cells that serve myotubes as a migration substrate on their way towards the apodemes. The results suggest that misexpression of more than 1.5% of the Drosophila genes can interfere with proper myotube guidance and/or muscle attachment. In addition to factors already known to participate in these processes, we identified a number of enzymes that participate in the synthesis or modification of protein carbohydrate side chains and in Ubiquitin modifications and/or the Ubiquitin-dependent degradation of proteins, suggesting that these processes are relevant for muscle pattern formation

Pre-Fibrillar α-Synuclein Mutants Cause Parkinson's Disease-Like Non-Motor Symptoms in Drosophila

Parkinson's disease (PD) is linked to the formation of insoluble fibrillar aggregates of the presynaptic protein α-Synuclein (αS) in neurons. The appearance of such aggregates coincides with severe motor deficits in human patients. These deficits are often preceded by non-motor symptoms such as sleep-related problems in the patients. PD-like motor deficits can be recapitulated in model organisms such as Drosophila melanogaster when αS is pan-neurally expressed. Interestingly, both these deficits are more severe when αS mutants with reduced aggregation properties are expressed in flies. This indicates that that αS aggregation is not the primary cause of the PD-like motor symptoms. Here we describe a model for PD in Drosophila which utilizes the targeted expression of αS mutants in a subset of dopadecarboxylase expressing serotonergic and dopaminergic (DA) neurons. Our results show that targeted expression of pre-fibrillar αS mutants not only recapitulates PD-like motor symptoms but also the preceding non-motor symptoms such as an abnormal sleep-like behavior, altered locomotor activity and abnormal circadian periodicity. Further, the results suggest that the observed non-motor symptoms in flies are caused by an early impairment of neuronal functions rather than by the loss of neurons due to cell death

Epidermal muscle attachment site-specific target gene expression and interference with myotube guidance in response to ectopic stripe expression in the developing Drosophila epidermis

The egr-type zinc-finger transcription factor encoded by the Drosophila gene stripe (sr) is expressed in a subset of epidermal cells to which muscles attach during late stages of embryogenesis. We report loss-of-function and gain-of-function experiments indicating that sr activity provides ectodermal cells with properties required for the establishment of a normal muscle pattern during embryogenesis and for the differentiation of tendon-like epidermal muscle attachment sites (EMA). Our results show that sr encodes a transcriptional activator which acts as an autoregulated developmental switch gene. sr activity controls the expression of EMA-specific target genes in cells of ectodermal but not of mesodermal origin. sr-expressing ectodermal cells generate long-range signals that interfere with the spatial orientation of the elongating myotubes

Bicoid associates with the 5′-cap-bound complex of caudal mRNA and represses translation

Translational control plays a key role in many biological processes including pattern formation during early Drosophila embryogenesis. In this process, the anterior determinant Bicoid (BCD) acts not only as a transcriptional activator of segmentation genes but also causes specific translational repression of ubiquitously distributed caudal (cad) mRNA in the anterior region of the embryo. We show that translational repression of cad mRNA is dependent on a functional eIF4E-binding motif. The results suggest a novel mode of translational repression, which combines the strategy of target-specific binding to 3′-untranslated sequences and interference with 5′-cap-dependent translation initiation in one protein