Fig. 4.

—Northern blot analysis of 3′ terminal ribonucleotide modifications. A small RNA sample purified from 96-h drone larvae was either subjected (+) or not subjected (−) to beta-elimination. Northern blots were probed for the predicted piRNA P4 (supplementary table S2, Supplementary Material online) and ame-mir-71. Beta-elimination did not affect the migration rate of the predicted piRNA, but did induce a faster migration of ame-mir-71 indicating that the former is modified at the 3′ end. (A) piRNA P4, unaltered after beta-elimination, (B) ame-mir-71, (C) short ame-mir-71 isomiR, (D) shortened ame-mir-71 after beta-elimination, (E) shortened isomiR.