Molecular characterization of genomic activities at the onset of zygotic transcription in mammals.
In rabbit embryos, zygotic transcripts are required for the development of the embryo only from the 8- to 16-cell stage onward, more than 44 h after fertilization (i.e., zygotic gene activation; ZGA). In order to characterize the first zygotic transcripts expressed in this species we used a suppression subtractive hybridization approach to isolate RNA that was present after the major transcriptional activation (morula stage), but absent at the 1-cell stage as maternal transcripts. One hundred fourteen differentially expressed inserts were selected and sequenced. A statistical analysis of expression patterns throughout the preimplantation period of development shows that genes transcribed from ZGA onward follow different patterns of expression. Considering their early post-ZGA behavior, we describe at least two main patterns: a gradual increase from ZGA onward, and a sharp increase in expression at ZGA followed by a marked decrease at the morula stage. Our data show that both ZGA and some early post-ZGA events are involved in the establishment of specific patterns of embryonic gene expression.
Pacheco-Trigon
Sylviane
S
Laboratoire de Biologie du Développement et Biotechnologie, INRA, 78352 Jouy en Josas Cedex, France.
Hennequet-Antier
Christelle
C
Oudin
Jean-François
JF
Piumi
François
F
Renard
Jean-Paul
JP
Duranthon
Véronique
V
D000818:Animals; D022202:Chromosomes, Artificial, Bacterial / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D047108:Embryonic Development; D005260:Female; D015870:Gene Expression; D015723:Gene Library; D016678:Genome; D008297:Male; D009028:Morula / Q000378:metabolism; D011247:Pregnancy; D012313:RNA / Q000032:analysis / Q000302:isolation & purification; D011817:Rabbits / Q000196:embryology* / Q000235:genetics*; D017422:Sequence Analysis, DNA; D014158:Transcription, Genetic; D015053:Zygote / Q000378:metabolism*
D018076:DNA, Complementary; D012313:RNA