Submitted July 30, 2007
Returned for revision August 17, 2007
Accepted October 26, 2007
Embryo
Identification of Genes Aberrantly Expressed in Mouse Embryonic Stem Cell-Cloned Blastocysts
Yuko Jincho ,
Yusuke Sotomaru ,
Manabu Kawahara ,
Hidehiko Ogawa ,
Yayoi Obata ,
and
Tomohiro Kono *
* To whom correspondence should be addressed. E-mail: tomohiro{at}nodai.ac.jp.
Abstract
During development, cloned embryos often undergo embryonic arrest at any stage of embryogenesis, leading to diverse morphological abnormalities. The long-term effects resulting from embryo cloning procedures would manifest after birth as early death, obesity, various functional disorders, etc. Despite extensive studies, the parameters affecting the developmental features of cloned embryos remain unclear. The present study carried out extensive gene expression analysis to screen a cluster of genes aberrantly expressed in embryonic stem (ES) cell-cloned blastocysts. Differential screening of cDNA subtraction libraries revealed 224 differentially expressed genes in the cloned blastocysts: 85 were identified by the BLAST search as known genes performing a wide range of functions. To confirm their differential expression, quantitative gene expression analysis were performed by real-time PCR using single blastocysts. The genes Skp1a, Canx, Ctsd, Timd2, and Psmc6 were significantly upregulated, while Aqp3, Ak3l1, Rhot1, Sf3b3, Nid1, mtRnr2, mtNd1, mtCytb, and mtCo2 were significantly down-regulated in the majority of ES cell-cloned embryos. The results here suggest that an extraordinarily high frequency of multiple functional disorders caused by the aberrant expression of various genes in the blastocyst stage is involved in developmental arrest and various other disorders in cloned embryos.
Key words:
Embryo •
Early development •
Gene regulation •
ES cell clone •
nuclear transfer
