The present inventors presumed that rice globulins accumulating in vacuole-derived type II protein bodies comprise a vacuolar translocating signal and proceeded to identify such a signal. As a result, fusion proteins composed of a 15 amino acid residue peptide of globulin, extending from the 72nd leucine residue to the 86th serine residue, added to the C terminus of GFP were surprisingly found to be intracellularly localized to non-vacuole-derived type I protein bodies (PB-I), and not to vacuole-derived type II protein bodies (PB-II). Furthermore, based on this 15 amino acid residue sequence, the consensus sequence "QCCXQ" (where X is an arbitrary amino acid), which is conserved in plants, was discovered. Accordingly, the present invention suggests that arbitrary peptides can be accumulated in plant endosperm tissues by adding the QCCXQ sequence thereto.