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Characterization of a novel Drosophila melanogaster cis‐regulatory module that drives gene expression to the larval tracheal system and adult thoracic musculature 下载免费PDF全文
Jorge Victor Wilfredo Cachay Wester Carlos Antonio Couto Lima Maiaro Cabral Rosa Machado Patrícia Vieira Zampar Simone Sakagute Tavares Nadia Monesi 《Genesis (New York, N.Y. : 2000)》2018,56(8)
In a previous bioinformatics analysis we identified 10 conserved Drosophila melanogaster sequences that reside upstream from protein coding genes (CGs). Here we characterize one of these genomic regions, which constitutes a Drosophila melanogaster cis‐regulatory module (CRM) that we denominate TT‐CRM. The TT‐CRM is 646 bp long and is located in one of the introns of CG32239 and resides about 3,500 bp upstream of CG13711 and about 620 bp upstream of CG12493. Analysis of 646 bp‐lacZ lines revealed that TT‐CRM drives gene expression not only to the larval, prepupal, and pupal tracheal system but also to the adult dorsal longitudinal muscles. The patterns of mRNA expression of the transgene and of the CGs that lie in the vicinity of TT‐CRM were investigated both in dissected trachea and in adult thoraces. Through RT‐qPCR we observed that in the tracheal system the pattern of expression of 646 bp‐lacZ is similar to the pattern of expression of CG32239 and CG13711, whereas in the thoracic muscles 646 bp‐lacZ expression accompanies the expression of CG12493. Together, these results suggest new functions for two previously characterized D. melanogaster genes and also contribute to the initial characterization of a novel CRM that drives a dynamic pattern of expression throughout development. 相似文献
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Back Cover: Prolonged in vivo functional assessment of the mouse oviduct using optical coherence tomography through a dorsal imaging window (J. Biophotonics 5/2018) 下载免费PDF全文
Optical coherence tomography through an implanted dorsal imaging window allows for prolonged in vivo structural and functional assessment of the mouse oviduct (Fallopian tube), including threedimensional structural imaging, quantitative measurements of the smooth muscle contraction, and mapping of cilia beat frequency. This method brings new opportunities for live studies and longitudinal analyses of mouse reproductive events in the native context. Further details can be found in the article by Shang Wang et al. ( e201700316 ).
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Roberto Chertoff Lior Soussan Hanno Roder Daniel M. Michaelson 《Cellular and molecular neurobiology》1995,15(2):269-281
Summary 1. Previous immunohistochemical studies led to the suggestion that distinctly phosphorylated neurofilament isoforms exist in different types of neurons. We have recently examined this hypothesis by direct biochemical experiments, which revealed that the heavy neurofilament protein NF-H of bovine ventral root cholinergic neurons is more acidic and markedly more phosphorylated than that of bovine dorsal root neurons.2. In the present study we employed this system to study the degree to which distinctly phosphorylated NF-H isoforms differ in the extents to which they can be phosphorylated and dephosphorylatedin vitro. This was performed utilizing alkaline phosphatase and protein kinase PK40ERK, which is specific to serines of Lys-Ser-Pro (KSP) repeats. The results obtained reveal that:3. The more extensively phosphorylated ventral root NF-H is dephosphorylated more rapidly than dorsal root NF-H.4. Ventral root NF-H and dorsal root NF-H in their native form are both poor substrates of PK40ERK.5. Following dephosphorylation, ventral root and dorsal root NF-H are phosphorylated extensively and differentially by this kinase. Under these conditions, PK40ERK catalyzes the incorporation of, respectively, 4.2±1.3 and 2.8±0.6 mol of phosphate per molecule of ventral root NF-H and dorsal root NF-H. The ratio of phosphates incorporated into ventral root NF-H to those incorporated into dorsal root NF-H is 1.46±0.17.6. These findings support the hypothesis that different classes of neurons contain distinctly phosphorylated neurofilaments and show that ventral root and dorsal root neurons are a useful model system for studying the distinct characteristics of neurofilament phosphorylation in different types of neurons. 相似文献
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Abstract: 5-HT1A autoreceptor antagonists enhance the effects of antidepressants by preventing a negative feedback of serotonin (5-HT) at somatodendritic level. The maximal elevations of extracellular concentration of 5-HT (5-HText ) induced by the 5-HT uptake inhibitor paroxetine in forebrain were potentiated by the 5-HT1A antagonist WAY-100635 (1 mg/kg s.c.) in a regionally dependent manner (striatum > frontal cortex > dorsal hippocampus). Paroxetine (3 mg/kg s.c.) decreased forebrain 5-HText during local blockade of uptake. This reduction was greater in striatum and frontal cortex than in dorsal hippocampus and was counteracted by the local and systemic administration of WAY-100635. The perfusion of 50 µmol/L citalopram in the dorsal or median raphe nucleus reduced 5-HText in frontal cortex or dorsal hippocampus to 40 and 65% of baseline, respectively. The reduction of cortical 5-HText induced by perfusion of citalopram in midbrain raphe was fully reversed by WAY-100635 (1 mg/kg s.c.). Together, these data suggest that dorsal raphe neurons projecting to striatum and frontal cortex are more sensitive to self-inhibition mediated by 5-HT1A autoreceptors than median raphe neurons projecting to the hippocampus. Therefore, potentiation by 5-HT1A antagonists occurs preferentially in forebrain areas innervated by serotonergic neurons of the dorsal raphe nucleus. 相似文献
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