Heat-shock response in Xenopus oocytes during meiotic maturation and activation

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Study of the distribution of metachromatic vacuoles and of acid phosphatase in the amoeba Amoeba proteus.

Journal Articleinfo:eu-repo/semantics/publishe

Etude de la distribution des vacuoles métachromatiques et de la phosphatase acide chez l'amide Amoeba proteus

info:eu-repo/semantics/publishe

Effets de l'acide α-lipoïque sur le métabolisme des acides nucléiques chez les embryons de Batraciens et de Poulet

Both the oxidized and the reduced forms of lipoic acid inhibit neural tube closure in pleurodeles and in chicken embryos. Oxidized lipoic acid inhibits the incorporation of H3-uridine and H3-cytidine into DNA; it inhibits the stage which involves the reduction of the ribonucleosides to the deoxyribonucleosides: in fact, the incorporation of H3-deoxyuridine is little or not at all affected by this substance. The action of reduced lipoic acid and reduced triphosphopyridine nucleotide on the reduction of ribose to deoxyribose is just the opposite of that exerted by oxidized lipoic acid. The addition of TPNH to oxidized lipoic acid prevents the inhibition of the incorporation of the ribonucleosides normally observed with oxidized lipoic acid. The degree of incorporation of H3-thymidine in the presence of these components appears to be "complementary" to the incorporation of H3-uridine and H3-cytidine into DNA. RNA metabolism is also deeply disturbed in embryos treated with oxidized or reduced lipoic acid. The effect of lipoic acid, whether oxidized or reduced, seems to be specific, since neither dithiodiglycol nor mercaptoethanol have the same effects on the incorporation of ribonucleosides into DNA. The significance of these autoradiographic findings is discussed; it is finally suggested that the arrest of morphogenesis might result from a disturbance of nucleic acid metabolism. © 1964.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Phosphorylation of Ribosomal Proteins during Maturation of Xenopus laevis Oocytes

The formation of an active maturation‐promoting factor and a strong burst of protein phosphorylation occur together at germinal vesicle breakdown in Xenopus oocytes undergoing maturation after progesterone Treatment. Here we show that one of the sites of this phosphorylation is the 40‐S ribosomal protein S6. This observation is discussed in relation to the known presence of a maturation promoting factor in somatic cells during the G2‐M transition and to the increase in S6 phosphorylation observed in cells treated with mitogenic stimuli. Copyright © 1981, Wiley Blackwell. All rights reservedSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Cytochemical detection of cytoplasmic deoxyribonucleic acid (DNA) in amphibian ovocytes

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Ribosomal preparations may induce maturation in Xenopus laevis oocytes

Xenopus laevis oocytes undergo maturation when they are injected with large quantities of crude ribosomes from various origins: X laevis full-grown or matured oocytes, Xenopus ovaries and embryos, Xenopus liver or mouse liver. All have the same efficiency, whatever their origin: they induce 50-90% maturation in the injected oocytes at about the same speed as progesterone treatment. The ribosomal preparations are inactive when injected into recipient oocytes pretreated with cholera toxin or cycloheximide. After dissociation of the ribosomes with 0.5 M KCl, the maturing activity was found to be associated with the high salt extract, but not with the subunits. Hypotheses concerning the mode of action of this ribosomal extract are discussed.SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe

A method for the extraction and characterization of RNA from subcellular fractions of Acetabularia

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Effets de l'acide lipoïque oxydé sur la synthèse de l'acide désoxyribonucléique chez les embryons de batraciens et de poulet

SCOPUS: ar.jSCOPUS: ar.jinfo:eu-repo/semantics/publishe

Induction of meiosis of Xenopus laevis oocytes by mianserine

SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe