The Entry/Gateway® cloning procedures for generating epitope-tagged fusion proteins using the P-element destination vectors. The procedures of Entry/Gateway® cloning are illustrated in the diagram as two major steps. (1) In the first step, a fragment encoding the open reading frame (ORF) is inserted into an entry vector to generate entry clones. Two entry vectors were described in this study: (i) the pGWS which uses a TA-based method; (ii) pENTR/D-TOPO (Invitrogen) which uses a TOPO-based method. (2) In the second step, the ORF in the entry clone is recombined into one of the P-DEST vectors.