Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Rouxs Arch Dev Biol
1990 Mar 01;1986:322-329. doi: 10.1007/BF00383770.
Show Gene links
Show Anatomy links
Expression of exogenously introduced bacterial chloramphenicol acetyltransferase genes in Xenopus laevis embryos before the midblastula transition.
Shiokawa K, Yamana K, Fu Y, Atsuchi Y, Hosokawa K.
???displayArticle.abstract???
Previous papers have reported that DNAs exogenously injected into Xenopus laevis fertilized eggs are expressed only at and after the midblastula transition (MBT). We have injected fertilized eggs of Xenopus laevis with circular plasmids that contained bacterial chloramphenicol acetyltransferase (CAT) genes connected to the promoter of viral genes (pSV2CAT and pAd12.E1aCAT) or the Xenopus cardiac actin gene (actin-CAT fusion gene), and examined whether these DNAs are expressed during the stage before the MBT. We found that expression of CAT enzyme can be detected before the MBT when CAT genes connected to viral promoters were injected. The activity was low during the cleavage stage on a per-embryo basis; however, the time course of the accumulation of the CAT enzyme activity roughly paralleled the increase in cell number. Therefore, CAT enzyme activity per cell was constant during cleavage and did not change dramatically before and after the MBT stage. CAT mRNA level, detected by CAT antisense RNA, was roughly proportional to the levels of CAT enzyme. Therefore, we assume that the observed enzyme activity reflects the transcriptional activity of injected CAT genes before and after the MBT. When the actin-CAT fusion gene was injected, however, no enzyme activity was detected until embryos had reached the neurula stage, a stage when endogenous actin genes are first activated. On the basis of these results, we conclude that the concept of an initial transcriptional activation of exogenous genes at amphibian MBT has to be changed. We propose that the expression of polymerase-II-transcribed genes is regulated by the nature of the promoters connected to the genes rather than by changes associated with MBT.
Atsuchi,
Level of histone H4 mRNA in Xenopus laevis embryonic cells cultured in the absence of cell adhesion.
1986, Pubmed,
Xenbase
Atsuchi,
Level of histone H4 mRNA in Xenopus laevis embryonic cells cultured in the absence of cell adhesion.
1986,
Pubmed
,
Xenbase Bakken,
Mapping of transcription initiation and termination signals on Xenopus laevis ribosomal DNA.
1982,
Pubmed
,
Xenbase Boterenbrood,
The direction of cleavage waves and the regional variation in the duration of cleavage cycles on the dorsal side of the Xenopus laevis blastula.
1986,
Pubmed
,
Xenbase Boterenbrood,
Duration of cleavage cycles and asymmetry in the direction of cleavage waves prior to gastrulation inXenopus laevis.
1983,
Pubmed Chulitskaia,
Desynchronization of cell divisions in the course of egg cleavage and an attempt at experimental shift of its onset.
1970,
Pubmed Colman,
Transcription of DNAs of known sequence after injection into eggs and oocytes of Xenopus laevis.
1975,
Pubmed
,
Xenbase Edgar,
Parameters controlling transcriptional activation during early Drosophila development.
1986,
Pubmed Etkin,
Distribution, expression and germ line transmission of exogenous DNA sequences following microinjection into Xenopus laevis eggs.
1987,
Pubmed
,
Xenbase Etkin,
Transformed Xenopus embryos as a transient expression system to analyze gene expression at the midblastula transition.
1985,
Pubmed
,
Xenbase Etkin,
Replication, integration and expression of exogenous DNA injected into fertilized eggs of Xenopus laevis.
1984,
Pubmed
,
Xenbase Forbes,
Small nuclear RNA transcription and ribonucleoprotein assembly in early Xenopus development.
1983,
Pubmed
,
Xenbase Fu,
Expression of circular and linearized bacterial chloramphenicol acetyltransferase genes with or without viral promoters after injection into fertilized eggs, unfertilized eggs and oocytes ofXenopus laevis.
1989,
Pubmed
,
Xenbase Gorman,
Recombinant genomes which express chloramphenicol acetyltransferase in mammalian cells.
1982,
Pubmed Griffith,
Regulation of ribosomal RNA synthesis in sea urchin embryos and oocytes.
1981,
Pubmed Kimelman,
The events of the midblastula transition in Xenopus are regulated by changes in the cell cycle.
1987,
Pubmed
,
Xenbase Krieg,
Developmental regulation of a gastrula-specific gene injected into fertilized Xenopus eggs.
1985,
Pubmed
,
Xenbase Kruczek,
Expression of the chloramphenicol acetyltransferase gene in mammalian cells under the control of adenovirus type 12 promoters: effect of promoter methylation on gene expression.
1983,
Pubmed Marini,
Persistence and replication of plasmid DNA microinjected into early embryos of Xenopus laevis.
1988,
Pubmed
,
Xenbase Melton,
Efficient in vitro synthesis of biologically active RNA and RNA hybridization probes from plasmids containing a bacteriophage SP6 promoter.
1984,
Pubmed Mohun,
Upstream sequences required for tissue-specific activation of the cardiac actin gene in Xenopus laevis embryos.
1986,
Pubmed
,
Xenbase Nakakura,
Synthesis of heterogeneous mRNA-like RNA and low-molecular-weight RNA before the midblastula transition in embryos of Xenopus laevis.
1987,
Pubmed
,
Xenbase Newport,
A major developmental transition in early Xenopus embryos: II. Control of the onset of transcription.
1982,
Pubmed
,
Xenbase Newport,
A major developmental transition in early Xenopus embryos: I. characterization and timing of cellular changes at the midblastula stage.
1982,
Pubmed
,
Xenbase Shiokawa,
Formation of nucleus-like structure in the cytoplasm of lambda-DNA-injected fertilized eggs and its partition into blastomeres during early embryogenesis in Xenopus laevis.
1986,
Pubmed
,
Xenbase Shiokawa,
Changes in the patterns of RNA synthesis in early embryogenesis of Xenopus laevis.
1989,
Pubmed
,
Xenbase Shiokawa,
Electron microscopic studies of giant nucleus-like structure formed by lambda DNA introduced into the cytoplasm of Xenopus laevis fertilized eggs and embryos.
1987,
Pubmed
,
Xenbase Shiokawa,
Persistence and expression of circular DNAs encoding Drosophila amylase, bacterial chloramphenicol acetyltransferase, and others in Xenopus laevis embryos.
1989,
Pubmed
,
Xenbase Shiokawa,
Pattern of RNA synthesis in isolated cells of Xenopus laevis embryos.
1967,
Pubmed
,
Xenbase Shiokawa,
Effects of the injection of exogenous DNAs on gene expression in early embryos and coenocytic egg cells ofXenopus laevis.
1989,
Pubmed
,
Xenbase Signoret,
Control of the expression of genes for DNA ligase in eukaryotes.
1986,
Pubmed Slater,
Transcriptive expression during sea urchin embryogenesis.
1970,
Pubmed Tashiro,
Determination of the rate of rRNA synthesis in Xenopus laevis triploid embryos produced by low-temperature treatment.
1983,
Pubmed
,
Xenbase Tashiro,
Preservation of Xenopus laevis rDNA-containing plasmid, pXlr101A, injected into the fertilized egg of Xenopus laevis.
1986,
Pubmed
,
Xenbase Tashiro,
Structural analysis of ribosomal DNA homologues in nucleolus-less mutant of Xenopus laevis.
1986,
Pubmed
,
Xenbase Wasylyk,
Enhancers and transcription factors in the control of gene expression.
1988,
Pubmed Wilson,
Tissue-specific expression of actin genes injected into Xenopus embryos.
1986,
Pubmed
,
Xenbase