Traditionally, the roles of only a few types of RNA have been understood for the significant part they play in cell biology. The short list includes messenger RNA, transfer RNA, and ribosomal RNA. More recently, other types have been added: mircroRNA, small interfering RNA, and antisense RNA.
But that hardly exhausts the list. A more recently discovered type of RNA is large, intergenic non-coding RNA (lincRNA), a particular subtype of long non-coding RNA. LincRNA are so-named because they are not derived from gene-coding DNA, but instead from stretches of DNA lying between genes. New research suggests that an important function of some lincRNAs is to regulate the development of embryonic stem cells in the earliest stages of embryo develpment.
Scientists at the Broad Institute of MIT and Harvard have discovered that a mysterious class of large RNAs plays a central role in embryonic development, contrary to the dogma that proteins alone are the master regulators of this process. The research, published online August 28 in the journal Nature, reveals that these RNAs orchestrate the fate of embryonic stem (ES) cells by keeping them in their fledgling state or directing them along the path to cell specialization.