Stem-cell research: A new genetic switching element
Thursday, May 22, 2014 - 19:21
in Biology & Nature
Every cell contains stored hereditary information, encoded in the sequence of nucleobases that make up its DNA. However, in any given cell type, only a fraction of this information is actually used. Which genes are activated and which are turned off is in part determined by a second tier of information which is superimposed on the nucleotide sequences that provide the blueprints for protein synthesis. This so-called epigenetic level of control is based on the localized, and in principle reversible, attachment of simple chemical tags to specific nucleotides in the genome. Slight modifications in genome sequences play a crucial role in the conversion of pluripotent stem cells into various differentiated cell types.