Martinez-Arias Lab
Department of Genetics, University of Cambridge
Chea Lu Lim
PhD student
cll36@cam.ac.ukDepartment of Genetics,
Downing Street, Cambridge
CB2 3EH,England
Telephone: +44 1223 766595
Fax: +44 1223 333992
I am interested in understanding how pluripotency in mouse embryonic stem cells is maintained and how this mechanism is different from the situation in the early mouse embryo.
Pluripotency is defined as the ability to give rise to all three germ layers and germ cells. Pluripotent cells exist transiently in the inner cell mass and epiblast cells of the early embryo but when these cells are cultured in vitro, they give rise to embryonic stem (ES) cells which can maintain their pluripotent state indefinitely.
In a typical population of ES cells, not all cells self-renew continuously, there is always a small proportion of spontaneously differentiating cells. In addition, when ES cells are induced to differentiate, only a proportion will do so in a stable manner. This feature has made it difficult to derive a particular cell type from ES cells efficiently, for use in therapy. The current mechanisms of pluripotency have so far failed to explain this observation adequately.
In addition, any mechanism must also be applicable to both ES cells and the embryo. There appears to be a fundamental difference between ES cells and their embryonic counterparts. ES cells, when placed back into the context of the embryo, are able to contribute to chimeric fetuses while ES cells aggregating together outside the embryo form embryoid bodies, which are multi-differentiated structures which lack any proper body plan.