Possible posttranscriptional modification sites of tRFs. (A) Genomic locus of the mature tRNAArg and flanking sequence is shown in italics and underlined letters, respectively. tRFs mapping to the 3' half of tRNAArg show non-templated CCA addition (red letters). (B) Logo of genomic tRNALeu sequence (top) and corresponding tRFs Logos from appressoria (middle) and mycelia (bottom) indicate possible posttranscriptional modification sites as indicated by dotted boxes. Numbers below Logo designate nucleotide position of the mature tRNALeu.