|Title||Rapid loss of Oct-4 and pluripotency in cultured rodent blastocysts and derivative cell lines.|
|Publication Type||Journal Article|
|Year of Publication||2003|
|Authors||Buehr M, Nichols J, Stenhouse FH, Mountford P, Greenhalgh CJ, Kantachuvesiri S, Brooker G, Mullins JJ, Smith AG|
|Date Published||2003 Jan|
|Keywords||Animals, Animals, Genetically Modified, Base Sequence, Blastocyst, Cell Differentiation, Cell Line, Chimera, Culture Techniques, DNA, Complementary, DNA-Binding Proteins, Gene Expression, In Situ Hybridization, Mice, Mice, Inbred CBA, Octamer Transcription Factor-3, Pluripotent Stem Cells, Rats, Rats, Inbred F344, Rats, Sprague-Dawley, Transcription Factors|
The POU transcription factor Oct-4 is essential for the pluripotent character of the mouse inner cell mass (ICM) and derivative embryonic stem (ES) cells. We analyzed the expression of Oct-4 during culture and establishment of cell lines from mouse and rat preimplantation embryos. Oct-4 was rapidly lost in primary outgrowths of the majority of cultured embryos prior to any evidence of morphological differentiation. Oct-4 persisted in only a minority of strain 129 cultures, which can go on to give ES cells. We used transgenic rats in which the dual reporter/selection marker beta-geo is under control of Oct-4 regulatory elements to investigate the effect of direct selection for Oct-4 expressing cells. Ablation of all cells occurred, consistent with complete downregulation of Oct-4. Without selection, in contrast, continuous cultures of morphologically undifferentiated cells could be derived readily from rat blastocysts and ICMs. However, these cells did not express significant Oct-4 and, although capable of differentiating into extraembryonic cell types, appeared incapable of producing fetal germ layer derivatives. Downregulation of Oct-4 appears to be a limiting factor in attempts to derive pluripotent cell lines from preimplantation embryos.
|Alternate Journal||Biol. Reprod.|