The gas and gadd family of genes, known collectively as the growth arrest genes, are associated with the negative control of @entity1 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 @entity19 embryo. The @entity70043 , @entity49432 , and @entity13841 ( @entity13841 , @entity13841 ) genes were expressed from the eight-cell stage onward. The @entity40027 and @entity16819 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 @entity12835 mRNA as a reference. The ratio of @entity70043 to @entity12835 mRNA was high at the eight-cell stage and fell three to fivefold during development. The decline in the @entity70043 : @entity12835 ratio corresponded to the activation of true cell growth (cytokinesis). The @entity49432 : @entity12835 ratio was low at the eight-cell stage and increased by twofold as the blastocyst formed. @entity13841 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 @entity13841 , @entity70043 , or @entity49432 mRNAs relative to @entity12835 . 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.

The growth arrest genes @entity70043 , @entity49432 , and @entity13841 ( @entity13841 ) are expressed in the XXXX preimplantation embryo.

@entity1 :: ('9606', 'Species') :: ['mammalian'] @entity70043 :: ('14455(Tax:10090)', 'Gene') :: ['gas5'] @entity40027 :: ('14453(Tax:10090)', 'Gene') :: ['gas2'] @entity16819 :: ('18858(Tax:10090)', 'Gene') :: ['gas3'] @entity12835 :: ('11461(Tax:10090)', 'Gene') :: ['beta-actin'] @entity13841 :: ('13198(Tax:10090)', 'Gene') :: ['Ddit3', 'gadd153', 'CHOP-10'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity49432 :: ('14456(Tax:10090)', 'Gene') :: ['gas6']
@entity19 :: (10090,Species) :: ['mouse']
