FIG. 2.

Optimization of rHA0 expression in Nicotiana benthamiana leaves. (A) Coomassie-stained SDS-PAGE gel. (B) Western blot probed with hemagglutinin-specific polyclonal antibodies. rHA0 expression levels in leaves were tested 5 days after inoculation with provector modules. Lanes 1 to 13 show 3′ module pICH30392, providing for rHA0 used in combination with different 5′ modules. The 3′ and 5′ modules were coinfiltrated with pICH14011, serving as the integrase source. Lane 1, 5′ module pICH20111, with a cytosolic location; lane 2, 5′ module pICH20155 with rice alpha-amylase SP; lane 3, 5′ module pICH20188 with Nicotiana plumbaginifolia calreticulin SP; lane 4, 5′ module pICH20199 with Phaseolus vulgaris PGIP SP; lane 5, 5′ module pICH20388 with apple pectinase SP; lane 6, 5′ module pICH20999 with barley alpha-amylase SP; lane 7, 5′ module pICH22488 with codon-optimized rice alpha-amylase SP; lane 8, 5′ module pICH20030 with chloroplast transit peptide; lane 9, 5′ module pICH22464 with N. plumbaginifolia calreticulin SP and a His₆ tag; lane 10, 5′ module pICH22455 with an N-terminal His₆ tag; lane 11, 5′ module pICH27757 with rice alpha-amylase SP and a His₆ tag; lane 12, 5′ module pICH27784 with barley alpha-amylase SP and a His₆ tag; lane 13, 5′ module pICH27770 with apple pectinase SP and a His tag; lane 14, 3′ module pICH7410 providing GFP in combination with 5′ module pICH20111. rHA0, recombinant full-length hemagglutinin from influenza virus A/NIBRG-14/2004 (H5N1); RbcL, large subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase.