qiRNAs are induced by DNA damage (25) and it is also well documented that plant short RNAs are involved in stress responses (26). Therefore, it is possible that expres- sion of other genes is also regulated by ex-siRNAs when the fungus grows in sub-optimal conditions or responds to diﬀerent signals to execute complex developmental processes, such as asexual sporulation or sexual inter- action. Finally, although we cannot rule out that miRNAs will be identiﬁed in other classes of fungi, the apparent lack of miRNAs in fungi raises the question whether miRNAs were present in a common eukaryotic ancestor and lost in fungi or appeared independently in plants and animals. The ﬁrst option is supported by the presence of miRNAs in green alga (13) and the latter is supported by the diﬀerences in miRNA biogenesis, degree of complementarity to the target mRNAs and lack of sequence homology between animal and plant miRNAs. ACCESSION NUMBER GEO GSE18958. 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