RRC ID 11766
Author Kobayashi S, Fujihara Y, Mise N, Kaseda K, Abe K, Ishino F, Okabe M.
Title The X-linked imprinted gene family Fthl17 shows predominantly female expression following the two-cell stage in mouse embryos.
Journal Nucleic Acids Res
Abstract Differences between male and female mammals are initiated by embryonic differentiation of the gonad into either a testis or an ovary. However, this may not be the sole determinant. There are reports that embryonic sex differentiation might precede and be independent of gonadal differentiation, but there is little molecular biological evidence for this. To test for sex differences in early-stage embryos, we separated male and female blastocysts using newly developed non-invasive sexing methods for transgenic mice expressing green fluorescent protein and compared the gene-expression patterns. From this screening, we found that the Fthl17 (ferritin, heavy polypeptide-like 17) family of genes was predominantly expressed in female blastocysts. This comprises seven genes that cluster on the X chromosome. Expression analysis based on DNA polymorphisms revealed that these genes are imprinted and expressed from the paternal X chromosome as early as the two-cell stage. Thus, by the time zygotic genome activation starts there are already differences in gene expression between male and female mouse embryos. This discovery will be important for the study of early sex differentiation, as clearly these differences arise before gonadal differentiation.
Volume 38(11)
Pages 3672-81
Published 2010-6-1
DOI 10.1093/nar/gkq113
PII gkq113
PMID 20185572
PMC PMC2887969
MeSH Animals Blastocyst / metabolism* Embryo, Mammalian / metabolism Female Ferritins / genetics* Gene Expression Profiling Genomic Imprinting* Male Mice Mice, Transgenic Multigene Family* Oligonucleotide Array Sequence Analysis Sex Differentiation / genetics* X Chromosome X Chromosome Inactivation
IF 11.147
Times Cited 22
Mice B6C3F1-Tg(CAG-EGFP)CX-FM038Osb