Search results for "sea urchin."

Functional characterization of the enhancer blocking element of the sea urchin early histone gene cluster reveals insulator properties and three esse…

2000

Insulator elements can be functionally identified by their ability to shield promoters from regulators in a position-dependent manner or their ability to protect adjacent transgenes from position effects. We have previously reported the identification of a 265 bp sns DNA fragment at the 3' end of the sea urchin H2A early histone gene that blocked expression of a reporter gene in transgenic embryos when placed between the enhancer and the promoter. Here we show that sns interferes with enhancer-promoter interaction in a directional manner. When sns is placed between the H2A modulator and the inducible tet operator, the modulator is barred from interaction with the basal promoter. However, th…

Apoptosis in sea urchin embryos.

1997

Abstract It is demonstrated by DNA electrophoresis analysis, morphological observations and TdT in situ reaction, that Paracentrotus embryos if treated with TPA plus heat undergo an apoptotic reaction. Indication is also obtained that non treated embryos undergo spontaneous apoptosis at the early pluteus stage, expecially in the districts of arms and intestine. The possible meaning of this latter observation is discussed.

Heavy Metals and Metalloids as Autophagy Inducing Agents: Focus on Cadmium and Arsenic

2012

In recent years, research on the autophagic process has greatly increased, invading the fields of biology and medicine. Several markers of the autophagic process have been discovered and various strategies have been reported studying this molecular process in different biological systems in both physiological and stress conditions. Furthermore, mechanisms of metalloid- or heavy metal-induced toxicity continue to be of interest given the ubiquitous nature and distribution of these contaminants in the environment where they often play the role of pollutants of numerous organisms. The aim of this review is a critical analysis and correlation of knowledge of autophagic mechanisms studied under …

Bioactive molecules from soil and marine bacteria: new potential applications

2015

Biological activities of the extracts from macroalgae Carpodesmia crinita, Carpodesmia brachycarpa, Asparagopsis taxiformis

2023

Marine species represent a rich source of biologically active products that can be used in various fields. Among them, marine algae produce numerous secondary metabolites responsible for different biological activities such as: immunomodulatory [1], antioxidant [2], and antimicrobial [3]. The aim of this study was chemically characterizing the extracts of three macroalgae species: Carpodesmia crinite (Duby) Orellana & Sansón, 2019, Carpodesmia brachycarpa (J. Agardh) Orellana & Sansón 2019, Asparagopsis taxiformis (Delile) Trevisan 1845 and evaluate their biological activities. The characterization of the secondary metabolites was performed by HPLC-MS and the results obtained showed…

Biochemical Studies on the Early Development of the Sea Urchin

1964

Heat Shock Proteins in Sea Urchin Embryos. (heat shock proteins/sea urchin embryos)

1989

Genes of the sea urchin embryo: An annotated list as of December 1994

1995

The main literature regarding gene structure and expression in sea urchin embryos is schematically reported and briefly commented upon. Although the subject has expanded particularly over the last 10 years, to which the review mostly refers, some historical reference is also given. More space is reserved to the regulation of the synthesis of histones and cytoskeletal actins, where the attention of various authors has been especially present; the regulation of such a synthesis is described both at a territorial level and a temporal level during the sea urchin development.

Cytochrome oxidase activity in the mitochondria of unfertilized and fertilized sea urchin eggs

1959

Abstract The cytochrome oxidase activity of isolated mitochondria of unfertilized and fertilized eggs of Paracentrotus lividus has been studied. It has been found that whereas in the mitochondria of unfertilized eggs saturation is reached at a cytochrome c concentration of 3.28 × 10−5 M, in those of fertilized eggs this occurs at a concentration of 5.74 × 10−5 M. It is shown that upon fertilization an increase of about 30 per cent of the activity of cytochrome oxidase takes place and no further changes appear to occur until blastula stage.

DNA amplification in sea urchin oocytes.

1978

In situ hybridization of ribosomal RNA withParacentrotus lividus ovaries suggests that ribosomal DNA undergoes amplification in the mononucleolate oocytes of this sea urchin.