Primary differentiation in the human blastocyst: comparative molecular portraits of inner cell mass and trophectoderm cells.
The primary differentiation event during mammalian development occurs at the blastocyst stage and leads to the delineation of the inner cell mass (ICM) and the trophectoderm (TE). We provide the first global mRNA expression data from immunosurgically dissected ICM cells, TE cells, and intact human blastocysts. Using a cDNA microarray composed of 15,529 cDNAs from known and novel genes, we identify marker transcripts specific to the ICM (e.g., OCT4/POU5F1, NANOG, HMGB1, and DPPA5) and TE (e.g., CDX2, ATP1B3, SFN, and IPL), in addition to novel ICM- and TE-specific expressed sequence tags. The expression patterns suggest that the emergence of pluripotent ICM and TE cell lineages from the morula is controlled by metabolic and signaling pathways, which include inter alia, WNT, mitogen-activated protein kinase, transforming growth factor-beta, NOTCH, integrin-mediated cell adhesion, phosphatidylinositol 3-kinase, and apoptosis. These data enhance our understanding of the first step in human cellular differentiation and, hence, the derivation of both embryonic stem cells and trophoblastic stem cells from these lineages.
Adjaye
James
J
Max-Planck Institute for Molecular Genetics (Department of Vertebrate Genomics), Ihnestrasse 73, D-14195 Berlin, Germany. adjaye@molgen.mpg.de
Huntriss
John
J
Herwig
Ralf
R
BenKahla
Alia
A
Brink
Thore C
TC
Wierling
Christoph
C
Hultschig
Claus
C
Groth
Detlef
D
Yaspo
Marie-Laure
ML
Picton
Helen M
HM
Gosden
Roger G
RG
Lehrach
Hans
H
D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D001755:Blastocyst / Q000166:cytology* / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D002460:Cell Line; D002999:Clone Cells; D004475:Ectoderm / Q000166:cytology* / Q000378:metabolism; D020869:Gene Expression Profiling; D006801:Humans; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D051880:Receptors, Notch / Q000378:metabolism; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014327:Trophoblasts / Q000166:cytology* / Q000378:metabolism
D015415:Biomarkers; D012333:RNA, Messenger; D051880:Receptors, Notch; D016212:Transforming Growth Factor beta; D020928:Mitogen-Activated Protein Kinases