Antisense RNAs everywhere?

In English In recent years, systematic searches of both prokaryote and eukaryote genomes have identified a staggering number of small RNAs, the biological functions of which remain unknown. Small RNA-based regulators are well known from bacterial plasmids. They act on target RNAs by sequence complementarity; that is, they are antisense RNAs. Recent findings suggest that many of the novel orphan RNAs encoded by bacterial and eukaryotic chromosomes might also belong to a ubiquitous, heterogeneous class of antisense regulators of gene expression.