Comparison of Gene Expression in Male and Female Mouse Blastocysts Revealed Imprinting of the X-Linked Gene, Rhox5/Pem, at Preimplantation Stages

Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
Current Biology (Impact Factor: 9.57). 02/2006; 16(2):166-72. DOI: 10.1016/j.cub.2005.11.071
Source: PubMed


Mammalian male preimplantation embryos develop more quickly than females . Using enhanced green fluorescent protein (EGFP)-tagged X chromosomes to identify the sex of the embryos, we compared gene expression patterns between male and female mouse blastocysts by DNA microarray. We detected nearly 600 genes with statistically significant sex-linked expression; most differed by 2-fold or less. Of 11 genes showing greater than 2.5-fold differences, four were expressed exclusively or nearly exclusively sex dependently. Two genes (Dby and Eif2s3y) were mapped to the Y chromosome and were expressed in male blastocysts. The remaining two (Rhox5/Pem and Xist) were mapped to the X chromosome and were predominantly expressed in female blastocysts. Moreover, Rhox5/Pem was expressed predominantly from the paternally inherited X chromosome, indicating sex differences in early epigenetic gene regulation.

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Available from: Nathan Mise, Oct 29, 2015
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    • "ene - dosage compensa - tion , which results in the phenotypic sexual dimorphism associated with DNA and RNA content . As mentioned above , a males ' faster growth was first described in mam - malsÀ Àyet this phylum utilizes the opposite heteromorphic sex chromosome pattern , and vast of majority of genes show higher expression in female embryos ( Kobayashi et al . , 2006 ) ."
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    • "It has been suggested that Rhox5 plays a vital role in the differentiation of embryonic stem cells. Rhox genes are abundant in E9.5 trophoblasts and Rhox5, which is localized in the X chromosome, is expressed predominantly in female mouse blastocysts rather than male blastocysts [30]. Embryonic stem cells with constitutively expressing Rhox5 (Pem) are not differentiated into the primitive endoderm nor embryonic ectoderm, but embryonic stem cells with constitutively expressing Rhox5 (Pem) developed into the teratoma containing only undifferentiated embryonic carcinoma-like cells. "
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    • "Thus, the double X-chromosome dosage in females and the presence of a Y-chromosome in males not only determine the transcriptional level of sex chromosome-encoded genes, but can also influence the transcription of genes present in autosomal chromosomes (Bermejo-Alvarez et al. 2010; Wijchers and Festenstein 2011). The use of sexing technologies, such as transgenesis and sex-sorted spermatozoa, in combination with microarray analysis of gene expression has uncovered nearly 600 differentially expressed genes between male and female mouse blastocysts (Kobayashi et al. 2006) and 3000 in the bovine model (Bermejo-Alvarez et al. 2010). These results confirm differences reported previously for some genes in male and female bovine blastocysts (Gutiérrez-Adán et al. 2000; Morton et al. 2007). "
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