Search results for "Larva"
showing 10 items of 632 documents
Stress response in Drosophila subobscura. II. Puff activity during anoxia and recovery from anoxia.
1987
When individuals of Drosophila subobscura at 0 hr prepupa are submitted to anoxia (4 hr and 24 hr, respectively), their puffing pattern is very similar to that shown by individuals at the moment of development in which treatment began. The same expression of genes (the same puffing pattern and the same protein pattern) is induced in this species by recovery from anoxia as well as by heat shock treatment at 31 degrees C.
Ocean acidification and elevated temperature negatively affect recruitment, oxygen consumption and calcification of the reef-building Dendropoma cris…
2019
Expected temperature rise and seawater pH decrease may affect marine organism fitness. By a transplant experiment involving air-temperature manipulation along a natural CO2 gradient, we investigated the effects of high pCO(2) (similar to 1100 mu atm) and elevated temperature (up to +2 degrees C than ambient conditions) on the reproductive success, recruitment, growth, shell chemical composition and oxygen consumption of the early life stages of the intertidal reef-building vermetid Dendropoma cristatum. Reproductive success was predominantly affected by temperature increase, with encapsulated embryos exhibiting higher survival in control than elevated temperature conditions, which were in t…
Warming Accelerates the Onset of the Molecular Stress Response and Increases Mortality of Larval Atlantic Cod
2022
Synopsis Temperature profoundly affects ectotherm physiology. Although differential thermal responses influence fitness, thus driving population dynamics and species distributions, our understanding of the molecular architecture underlying these responses is limited, especially during the critical larval stage. Here, using RNA-sequencing of laboratory-reared Atlantic cod (Gadus morhua) larvae of wild origin, we find changes in gene expression in thousands of transcripts consistent with a severe cellular stress response at both ambient and projected (+2°C and +4°C) temperatures. In addition, specific responses to stress, heat, and hypoxia were commonly identified in gene ontology enrichment …
The stream-dwelling tadpole ofHyloscirtus charazani(Anura: Hylidae) from Andean Bolivia
2005
Abstract We describe the lotic larva of Hyloscirtus charazani from Charazani and nearby areas, Departamento La Paz, Bolivia (2700–3200 m a.s.l.). It is morphologically undistinguishable from tadpoles of H. armatus sensu lato. These tadpoles show stream adaptation through a robust body with strong tail musculature, enlarged oral disc, increased number of labial tooth rows, and complete marginal papillae. Furthermore, they have a large saccular structure that underlies the limb buds, encloses the vent tube, and partially covers the hindlimbs during their development. Resumen Describimos la larva lotica de Hyloscirtus charazani de Charazani y de otra localidad cercana, Departamento La Paz, Bol…
Oxygen consumption of F0 and F1 larval and juvenile European seabass Dicentrarchus labrax in resonse to ocean acidification and warming
2022
Ongoing climate change is leading to warmer and more acidic oceans. The future distribution of fish within the oceans depends on their capacity to adapt to these new environments. Only few studies have examined the effects of ocean acidification (OA) and warming (OW) on the metabolism of long-lived fish over successive generations. We therefore aimed to investigate the effect of OA on larval and juvenile growth and metabolism on two successive generations of European sea bass (Dicentrarchus labrax L.) as well as the effect of OAW on larval and juvenile growth and metabolism of the second generation. European sea bass is a large economically important fish species with a long generation time…
Dual-beam confocal light-sheet microscopy via flexible acousto-optic deflector
2019
Confocal detection in digital scanned laser light-sheet fluorescence microscopy (DSLM) has been established as a gold standard method to improve image quality. The selective line detection of a complementary metal-oxide-semiconductor camera (CMOS) working in rolling shutter mode allows the rejection of out-of-focus and scattered light, thus reducing background signal during image formation. Most modern CMOS have two rolling shutters, but usually only a single illuminating beam is used, halving the maximum obtainable frame rate. We report on the capability to recover the full image acquisition rate via dual confocal DSLM by using an acoustooptic deflector. Such a simple solution enables us t…
ISWI Regulates Higher-Order Chromatin Structure and Histone H1 Assembly In Vivo
2007
Imitation SWI (ISWI) and other ATP-dependent chromatin-remodeling factors play key roles in transcription and other processes by altering the structure and positioning of nucleosomes. Recent studies have also implicated ISWI in the regulation of higher-order chromatin structure, but its role in this process remains poorly understood. To clarify the role of ISWI in vivo, we examined defects in chromosome structure and gene expression resulting from the loss of Iswi function in Drosophila. Consistent with a broad role in transcriptional regulation, the expression of a large number of genes is altered in Iswi mutant larvae. The expression of a dominant-negative form of ISWI leads to dramatic a…
Food-mediated modulation of immunity in a phytophagous insect: An effect of nutrition rather than parasitic contamination.
2015
7 pages; International audience; Inherent to the cost of immunity, the immune system itself can exhibit tradeoffs between its arms. Phytophagous insects face a wide range of microbial and eukaryotic parasites, each activating different immune pathways that could compromise the activity of the others. Feeding larvae are primarily exposed to microbes, which growth is controlled by antibiotic secondary metabolites produced by the host plant. The resulting variation in abundance of microbes on plants is expected to differentially stimulate the insect antimicrobial immune defenses. Under the above tradeoff hypothesis, stimulation of the insect antimicrobial defenses is expected to compromise imm…
Molecular characterization of a male-specific glycosyl hydrolase, Lma-p72, secreted on to the abdominal surface of the Madeira cockroach Leucophaea m…
2003
0264-6021 (Print) Journal Article Research Support, Non-U.S. Gov't; The epicuticular surface protein Lma-p72 is specific to the abdominal secretions of Leucophaea maderae (Madeira cockroach) adult males. Natural Lma-p72 was purified and the complete cDNA sequence determined by reverse-transcription PCR using primers based on Edman degradation fragments. Northern blot and in situ hybridization analyses showed that Lma-p72 was expressed in the tergal and sternal glands. Sequence alignment indicates that Lma-p72 is closely related to the family 1 glycosyl hydrolases (EC 3.2.1). Native Lma-p72 was proved to be active in the abdominal secretions and exhibit a beta-galactosidase-like activity. Ho…
Jack of all trades, master of all: a positive association between habitat niche breadth and foraging performance in pit-building antlion larvae.
2012
Species utilizing a wide range of resources are intuitively expected to be less efficient in exploiting each resource type compared to species which have developed an optimal phenotype for utilizing only one or a few resources. We report here the results of an empirical study whose aim was to test for a negative association between habitat niche breadth and foraging performance. As a model system to address this question, we used two highly abundant species of pit-building antlions varying in their habitat niche breadth: the habitat generalist Myrmeleon hyalinus, which inhabits a variety of soil types but occurs mainly in sandy soils, and the habitat specialist Cueta lineosa, which is restr…