TY - JOUR AU - Fattash, Isam AU - Voß, Björn AU - Reski, Ralf AU - Hess, Wolfgang R. AU - Frank, Wolfgang PY - 2007 DA - 2007/03/14 TI - Evidence for the rapid expansion of microRNA-mediated regulation in early land plant evolution JO - BMC Plant Biology SP - 13 VL - 7 IS - 1 AB - MicroRNAs (miRNAs) are regulatory RNA molecules that are specified by their mode of action, the structure of primary transcripts, and their typical size of 20–24 nucleotides. Frequently, not only single miRNAs but whole families of closely related miRNAs have been found in animals and plants. Some families are widely conserved among different plant taxa. Hence, it is evident that these conserved miRNAs are of ancient origin and indicate essential functions that have been preserved over long evolutionary time scales. In contrast, other miRNAs seem to be species-specific and consequently must possess very distinct functions. Thus, the analysis of an early-branching species provides a window into the early evolution of fundamental regulatory processes in plants. SN - 1471-2229 UR - https://doi.org/10.1186/1471-2229-7-13 DO - 10.1186/1471-2229-7-13 ID - Fattash2007 ER -