The DNA puff BhC4-1 gene, located in DNA puff C4 of Bradysiahygida, is amplified and expressed in the salivary gland at the end of the fourth larval instar as a late response to the increase in 20-hydroxyecdysone titer that triggers metamorphosis. Functional studies revealed that the mechanisms that regulate BhC4-1 expression in the salivary gland are conserved in transgenic Drosophila. These studies also led to the identification of a cis-regulatory module that drives developmentally regulated expression of BhC4-1-lacZ in the prothoracic gland cells of the ring gland, a compound organ which in Drosophila results from the fusion of the prothoracic glands, the corpus allatum and the corpus cardiacum.
View Article and Find Full Text PDFA large number of functional neuroimaging studies have investigated the brain circuitry which is engaged during performance of phonological verbal fluency tasks, and the vast majority of these have been carried out in English. Although there is evidence that this paradigm varies depending on the language spoken, it is unclear if this difference is associated with differences in brain activation patterns. Also, there is neuroimaging evidence that the patterns of regional cerebral activation during verbal fluency tasks may vary with the level of task demanded.
View Article and Find Full Text PDFRecently we have shown that BhSGAMP-1 is a developmentally regulated reiterated gene that encodes an antimicrobial peptide (AMP) and is expressed exclusively in the salivary glands, at the end of the larval stage. We show, for the first time, that a gene for an AMP is directly activated by 20-OH ecdysone. This control probably involves the participation of short-lived repressor(s).
View Article and Find Full Text PDFGene amplification occurs in Bradysia hygida salivary glands, at the end of the fourth larval instar. The hormone 20-hydroxyecdysone (20E) triggers this process, which results in DNA puff formation. Amplified genes are activated in two distinct groups.
View Article and Find Full Text PDFIt has recently become clear that the innate immune systems of insects and mammals are highly conserved; in general, these systems are stimulated upon infection by microorganisms. We found in the fly Bradysia hygida, a reiterated gene, which codes for a secretory peptide similar to plant-seed antimicrobial peptides. This gene BhSGAMP-1 is activated and expressed exclusively in the salivary glands of the larvae, while they are preparing to molt.
View Article and Find Full Text PDFIn this work, we present biochemical and morphological evidence that the final steps of programmed cell death (PCD) in the salivary glands of the inferior Diptera, Bradysia hygida, present apoptotic characteristics. In B. hygida, elimination of salivary glands is preceded by the establishment of a typical pattern of protein synthesis; increase in caspase activity; decrease in cell volume; nuclear pyknosis; nuclear DNA breakage; changes in the actin cytoskeleton; and most importantly, destruction of giant cells via formation of apoptotic bodies containing broken DNA or cytoplasm remains.
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