HP and infection: The idea of the predicted HP structure-sequence being protected from cleavage by DCL in planta is strengthened by the observation that transient expression of a GFP construct containing a 3′ IGR-HP structure sequence did not reveal an elevated level of HP-derived siRNAs either and, relative to the 3′ part of the preceding ORF (Fig. 8, part FP of the GFP gene), showed similarity to the siRNA level produced from this sequence during a natural infection cycle, while the amounts from the N gene-based 3′UTR control sequence were relatively equal to those from the 3′ part of the preceding ORF.