MicroRNA involvement in Embryonic stem cell pluripotency maintenance and fate determination

Descrizione: Embryonic stem (ES) cells, which are derived from the inner cell mass (ICM) of the mammalian blastocyst, have the capability of apparent indefinite self-renewing and are pluripotent. These features therefore make ES cells ideal for their application in regenerative medicine, but their use may have ethical implications. Recently it has been shown the possibility of cellular reprogramming of somatic cells into pluripotent induced (IP) ES-like cells, which may overcome this problem. A strong inter-connective network of regulation of gene expression, which may include also microRNAs, is involved in the formation of the ICM and the maintenance of this stem cell pool during the development of the pre-implantation embryo. Elucidating pluripotency at a molecular level underlie the opportunity of an effective production of IPs suitable for clinical applications. In order to achieve this goal we investigate the ES transcriptome using two different approaches: suppressive subtractive hybridization that allowed us to generate subtracted cDNA libraries specific for the early events associated with the loss of pluripotency, and a microarray-based approach to identify microRNAs potentially involved in ES cells fate determination. The identification of the earliest transcripts (both mRNAs and microRNAs) associated with chromatin reorganization and loss of pluripotency allowed us to identify several candidate members of the complex network which regulate the establishment of new gene expression programs that accompany lineage specification and cellular reprogramming.