title: The growth arrest genes gas5, gas6, and CHOP-10 (gadd153) are expressed in the mouse preimplantation embryo.
abstract: The gas and gadd family of genes, known collectively as the growth arrest genes, are associated with the negative control of mammalian cell growth. The steady-state levels of their mRNAs are increased by three to fivefold when exponentially multiplying cells are exposed to a variety of stresses including inadequate nutrition or the removal of serum. Reverse transcription-polymerase chain reaction (RT-PCR) has been used to analyze growth arrest gene expression in the preimplantation mouse embryo. The gas5, gas6, and CHOP-10 (gadd153, Ddit3) genes were expressed from the eight-cell stage onward. The gas2 and gas3 genes associated with apoptosis were not expressed. Embryos were cultured in kSOM medium and a semiquantitative RT-PCR method was used to measure the relative gene expression using beta-actin mRNA as a reference. The ratio of gas5 to beta-actin mRNA was high at the eight-cell stage and fell three to fivefold during development. The decline in the gas5:beta-actin ratio corresponded to the activation of true cell growth (cytokinesis). The gas6:beta-actin ratio was low at the eight-cell stage and increased by twofold as the blastocyst formed. CHOP-10 was expressed at a constant level throughout development. Embryos that had developed in vivo were compared with the equivalent blastocyst-stage embryos cultured in kSOM medium. There were no significant differences in the ratio of CHOP-10, gas5, or gas6 mRNAs relative to beta-actin. These results suggest that these genes are expressed as part of normal early embryonic development. The potential roles of the growth arrest genes are discussed.
authors.affiliation: Rowett Research Institute, Aberdeen, Scotland, United Kingdom.
authors.forename: J V
authors.initials: JV
authors.lastname: Fleming
authors.forename: N
authors.initials: N
authors.lastname: Fontanier
authors.forename: D N
authors.initials: DN
authors.lastname: Harries
authors.forename: W D
authors.initials: WD
authors.lastname: Rees
mesh_terms: D016475:3T3 Cells; D000199:Actins / Q000096:biosynthesis; D000818:Animals; D001755:Blastocyst / Q000166:cytology / Q000378:metabolism*; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D036341:Intercellular Signaling Peptides and Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D009687:Nuclear Proteins / Q000096:biosynthesis* / Q000235:genetics; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics; D012313:RNA / Q000032:analysis; D051742:Transcription Factor CHOP; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics; D014158:Transcription, Genetic; D000099255:Growth Arrest-Specific Protein 6
chemical_list: D000199:Actins; D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D036341:Intercellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D011506:Proteins; D012313:RNA; D051742:Transcription Factor CHOP; D014157:Transcription Factors; D000099255:Growth Arrest-Specific Protein 6; C497250:Ddit3 protein, mouse