title: Evolutionary conservation of the oocyte transcriptome among vertebrates and its implications for understanding human reproductive function.
abstract: Cross-phylum and cross-species comparative transcriptomic analyses provide an evolutionary perspective on how specific tissues use genomic information. A significant mRNA subset present in the oocytes of most vertebrates is stabilized or stored for post-LH surge use. Since transcription is arrested in the oocyte before ovulation, this RNA is important for completing maturation and sustaining embryo development until zygotic genome activation. We compared the human oocyte transcriptome with an oocyte-enriched subset of mouse, bovine and frog (Xenopus laevis) genes in order to evaluate similarities between species. Graded temperature stringency hybridization on a multi-species oocyte cDNA array was used to measure the similarity of preferentially expressed sequences to the human oocyte library. Identity analysis of 679 human orthologs compared with each identified official gene symbol found in the subtractive (somatic-oocyte) libraries comprising our array revealed that bovine/human similarity was greater than mouse/human or frog/human similarity. However, based on protein sequence, mouse/human similarity was greater than bovine/human similarity. Among the genes over-expressed in oocytes relative to somatic tissue in Xenopus, Mus and Bos, a high level of conservation was found relative to humans, especially for genes involved in early embryonic development.
authors: Centre de Recherche en Biologie de la Reproduction, Département des Sciences Animales, Université Laval, Québec, QC, Canada G1V 0A6.
authors: Eve-Lyne
authors: EL
authors: Sylvestre
authors: Claude
authors: C
authors: Robert
authors: Sophie
authors: S
authors: Pennetier
authors: Rémi
authors: R
authors: Labrecque
authors: Isabelle
authors: I
authors: Gilbert
authors: Isabelle
authors: I
authors: Dufort
authors: Marie-Claude
authors: MC
authors: Léveillé
authors: Marc-André
authors: MA
authors: Sirard
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D002417:Cattle; D017124:Conserved Sequence; D004622:Embryo, Mammalian; D004625:Embryo, Nonmammalian; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D011247:Pregnancy; D017386:Sequence Homology, Amino Acid; D059467:Transcriptome; D014982:Xenopus laevis / Q000196:embryology / Q000235:genetics*
keywords: comparative genomics; oocyte genes; system biology; transcriptomics