Search results for "Ascidia"
showing 10 items of 63 documents
Inflammatory responses of the ascidian Ciona intestinalis.
2008
«Correlation between granulocytes and tunic cuticle of Ciona intestinalis (Tunicata, Ascidiacea) as evaluated by microscopy»
2012
The tunic is a peculiar integumentary tissue covering the epidermis of ascidians and other tunicates. It is an extracellular matrix whose outermost surface is revealed to be a continuos layer called tunic cuticle, composed of electron dense fibrous materials. Mechanisms occurring during the growth of the animal after metamorphosis, must assure the maintenance of the thin tunic cuticle density and integrity as it represents the primary body surface barrier preventing the mechanical and microbial assaults. Investigations by optical and electron microscopy on tunic samples from young Ciona intestinalis, allowed us to study morphological relationship between the tunic cuticle architecture and g…
Citochine nell'ascidia Ciona intestinalis.
2011
Tributyltin chloride-induced effects on protein tyrosine phosphorylation and on extracellular-signal-regulated kinase (ERK) phosphorilation in Ascidi…
2011
Ascidians represent an intriguing candidate experimental system for studying the effects of environmental stress. We studied TBT effects and probable related pathways were investigated on ascidian embryos by using Western immunoblotting. Among the various signal transduction pathways involved in response to environmental stress, both tyrosine kinase signalling and MAPKs have been played a significant role. To better understand molecular mechanisms after exposure to TBT we studied the two signal transduction pathways above mentioned. Attempting to unravel the molecular effects of TBT-induced on ascidians embryogenesis, TBT treatments carried out in Phallusia mammillata embryos at gastrula st…
Effects of tributyltin chloride in ascidian embryos: modulation of kinase-mediated signalling pathways
2009
We studied the effects of various TBT concentrations by assaying the activity of ERK 1/2 (p44/42) and phospho-ERK1/2 (phospho-p44/42), proteins with a key role in ascidian development, and tyrosine kinase-dependent pathway. The effects of this xenobiotic and the role of some signalling mechanisms on ascidian embryos were examined by using Western immunoblotting. The tyrosine phosphorylation pattern in the ascidians Ciona intestinalis and Phallusia mammillata development was examined and different levels of protein phosphorylation were found as a response to TBT at μM range. To determine whether another key signalling pathway was activated, the effects of TBT on the phosphorylation state of …
Ag-NOR and C-banding analysis of spermatocyte chromosomes ofClavelina lepadiformis(Ascidiacea, Aplousobranchiata)
1991
SUMMARYChromosome number n = 9 and 2n = 18 for Clavelina lepadiformis (Ascidiacea, Aplousobranchiata) from the Gulf of Palermo have been determined. Silver staining analysis of testicular cells reveals that within-individual variability in NOR banding patterns is present. Using the C-banding procedure, a very impressive heterochromatin amount seems to characterize the chromosome set of this species.
Hemocyte migration during inflammatory-like reaction of Ciona intestinalis (Tunicata, ascidiacea).
2000
Following an injuring factor such as the injection of erythrocytes into the tunic of Ciona intestinalis, an inflammatory-like response occurs and blood cells are massively involved in these mechanisms. Electron microscope observations illustrate the infiltration and migration of blood cells throughout the mantle epithelium into the tunic and show several prominent morphological changes.
Inflammatory Response of the Ascidian Ciona intestinalis
2016
Abstract The Ciona intestinalis inflammatory response to several irritants appears to be composed of a complex reaction set. The cellular reactions in the tunic involve hemocyte infiltration, hemocyte and epidermis activities, vacuolization, and cell disruption, while cell products can contribute to form capsule components and/or cause a tunic wound. In this response, the involvement of the pharynx, as the main immune-competent organ, has been disclosed by a lipopolysaccharide challenge that upregulates innate immunity genes and transcription activation genes. The pharynx responds through hemocyte recruitment into the pharynx vessels, enhancement of galectin-like lectins in the serum hemoly…
Localization of antimicrobial peptides in the tunic of Ciona intestinalis (Ascidiacea, Tunicata) and their involvement in local inflammatory-like rea…
2011
AbstractTunicates comprising a wide variety of different species synthesize antimicrobial peptides as important effector molecules of the innate immune system. Recently, two putative gene families coding for antimicrobial peptides were identified in the expressed sequence tag database of the tunicate Ciona intestinalis. Two synthetic peptides representing the cationic core region of one member of each of the families displayed potent antibacterial and antifungal activities. Moreover, the natural peptides were demonstrated to be synthesized and stored in distinct hemocyte types. Here, we investigated the presence of these natural peptides, namely Ci-MAM-A and Ci-PAP-A, in the tunic of C. int…