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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2007.08.011 Byline: Richard Paul Sorrentino, Tsuyoshi Tokusumi, Robert A. Schulz Keywords: Drosophila hematopoiesis; Hemocyte proliferation; hopscotch.sup.Tumorous-lethal ; Lamellocyte differentiation; Tumor suppressor; U-shaped Abstract: Drosophila has emerged as an important model system to discover and analyze genes controlling hematopoiesis. One regulatory network known to control hemocyte differentiation is the Janus kinase (JAK)/Signal Transducer and Activator of Transcription (STAT) signal-transduction pathway. A constitutive activation mutation of the Janus kinase Hopscotch (hopscotch.sup.Tumorous-lethal ; hop.sup.Tum-l) results in a leukemia-like over-proliferation of hemocytes and copious differentiation of lamellocytes during larval stages. Here we show that the Friend of GATA (FOG) protein U-shaped (Ush) is expressed in circulating and lymph gland hemocytes, where it plays a critical role in controlling blood cell proliferation and differentiation. Our findings demonstrate that a reduction in ush function results in hematopoietic phenotypes strikingly similar to those observed in hop.sup.Tum-l animals. These include lymph gland hypertrophy, increased circulating hemocyte concentration, and abundant production of lamellocytes. Forced expression of N-terminal truncated versions of Ush likewise leads to larvae with severe hematopoietic anomalies. In contrast, expression of wild-type Ush results in a strong suppression of hop.sup.Tum-l phenotypes. Taken together, our findings demonstrate that U-shaped acts to control larval hemocyte proliferation and suppress lamellocyte differentiation, likely regulating hematopoietic events downstream of Hop kinase activity. Such functions appear to be facilitated through Ush interaction with the hematopoietic GATA factor Serpent (Srp). Author Affiliation: Department of Biochemistry and Molecular Biology, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA Article History: Received 21 March 2007; Revised 20 July 2007; Accepted 6 August 2007

The role of serpent and lozenge chemicals in drosophila GATA gene regulation in animals is examined.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2005.09.039 Byline: Kathleen M. Gajewski, Jianbo Wang, Robert A. Schulz Keywords: Calcineurin; Drosophila; Hypercontraction; Indirect flight muscle; Myosin heavy chain; Troponin I Abstract: Mutations in the Drosophila calcineurin B2 gene cause the collapse of indirect flight muscles during mid stages of pupal development. Examination of cell fate-specific markers indicates that unlike mutations in genes such as vestigial, calcineurin B2 does not cause a shift in cell fate from indirect flight muscle to direct flight muscle. Genetic and molecular analyses indicate a severe reduction of myosin heavy chain gene expression in calcineurin B2 mutants, which accounts at least in part for the muscle collapse. Myofibrils in calcineurin B2 mutants display a variety of phenotypes, ranging from normal to a lack of sarcomeric structure. Calcineurin B2 also plays a role in the transition to an adult-specific isoform of troponin I during the late pupal stages, although the incompleteness of this transition in calcineurin B2 mutants does not contribute to the phenotype of muscle collapse. Together, these findings suggest a molecular basis for the indirect flight muscle hypercontractility phenotype observed in flies mutant for Drosophila calcineurin B2. Author Affiliation: Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA Article History: Received 8 July 2005; Revised 15 September 2005; Accepted 21 September 2005

Calcineurin signaling has been implicated in a broad spectrum of developmental processes in a variety of organ systems. Calcineurin is a calmodulin-dependent, calcium-activated protein phosphatase composed of catalytic and regulatory subunits. The serine/threonine-specific phosphatase functions within a signal transduction pathway that regulates gene expression and biological responses in many developmentally important cell types. Calcineurin signaling was first defined in T lymphocytes as a regulator of nuclear factor of activated T cells (NFAT) transcription factor nuclear translocation and activation. Recent studies have demonstrated the vital nature of calcium/calcineurin/NFAT signaling in cardiovascular and skeletal muscle development in vertebrates. Inhibition, mutation, or forced expression of calcineurin pathway genes result in defects or alterations in cardiomyocyte maturation, heart valve formation, vascular development, skeletal muscle differentiation and fiber-type switching, and cardiac and skeletal muscle hypertrophy. Conserved calcineurin genes are found in invertebrates such as Drosophila and Caenorhabditis elegans, and genetic studies have demonstrated specific myogenic functions for the phosphatase in their development. The ability to investigate calcineurin signaling pathways in vertebrates and model genetic organisms provides a great potential to more fully comprehend the functions of calcineurin and its interacting genes in heart, blood vessel, and muscle development. Keywords: Calcineurin; NFAT; Signal transduction; Cardiomyocyte; Hypertrophy; Valvuloseptal development; Vascular development; Skeletal muscle; Fibertype specialization; Drosophila; Interacting genes; Indirect flight muscle; C. elegans

Introduction: The WHO estimates that each year 5 million people are left permanently disabled after stroke. Adjuvant treatments to promote the effects of rehabilitation are urgently needed. Cortical excitability and neuroplasticity can be enhanced by non-invasive brain stimulation but evidence from sufficiently powered, randomized controlled multi-center clinical trials is absent. Methods: Neuroregeneration enhanced by transcranial direct current stimulation (tDCS) in stroke (NETS) tested efficacy and safety of anodal tDCS to the primary motor cortex of the lesioned hemisphere in the subacute phase (day 5–45) after cerebral ischemia. Stimulation was combined with standardized rehabilitative training and repeatedly applied in 10 sessions over a period of 2 weeks in a planned sample of 120 patients. Primary outcome parameter was upper-extremity function at the end of the 2-weeks intervention period of active treatment or placebo (1:1 randomization), measured by the upper-extremity Fugl-Meyer assessment. Sustainability of the treatment effect was evaluated by additional follow-up visits after 30 and 90 days. Further secondary endpoints included metrics of arm and hand function, stroke impact scale, and the depression module of the patient health questionnaire. Perspective: NETS was aimed at providing evidence for an effective and safe adjuvant treatment for patients after stroke. Trial registration: ClinicalTrials.gov Identifier NCT00909714. Registered May 28, 2009. [ABSTRACT FROM AUTHOR]

The embryonic dorsal vessel in Drosophila possesses anteroposterior polarity and is subdivided into two chamber-like portions, the aorta in the anterior and the heart in the posterior. The heart portion features a wider bore as compared with the aorta and develops inflow valves (ostia) that allow the pumping of hemolymph from posterior toward the anterior. Here, we demonstrate that homeotic selector genes provide positional information that determines the anteroposterior subdivision of the dorsal vessel. Antennapedia (Antp), Ultrabithorax (Ubx), abdominal-A (abd-A), and Abdominal-B (Abd-B) are expressed in distinct domains along the anteroposterior axis within the dorsal vessel, and, in particular, the domain of abd-A expression in cardioblasts and pericardial cells coincides with the heart portion. We provide evidence that loss of abd-A function causes a transformation of the heart into aorta, whereas ectopic expression of abd-A in more anterior cardioblasts causes the aorta to assume heart-like features. These observations suggest that the spatially restricted expression and activity of abd-A determine heart identities in cells of the posterior portion of the dorsal vessel. We also show that Abd-B, which at earlier stages is expressed posteriorly to the cardiogenic mesoderm, represses cardiogenesis. In light of the developmental and morphological similarities between the Drosophila dorsal vessel and the primitive heart tube in early vertebrate embryos, these data suggest that Hox genes may also provide important anteroposterior cues during chamber specification in the developing vertebrate heart. Key Words: cardiogenesis; heart patterning; dorsal vessel; homeotic genes; abd-A; Abd-B; Hox genes.