The discovery of microRNAs encoded by papillomaviruses supports the important role of these small molecules in persistent infection, according to a study published July 26 in the open-access journal PLOS Pathogens. Study author Rachel Chirayil of the University of Texas at Austin and colleagues made this discovery using a new approach that enables microRNA identification for the enormous range of pathogens that have genomic data but cannot be cultured in a laboratory setting.