Transient expression of Ss ChlI in N. benthamiana. A) Schematic of expression constructs (abbreviations as in Figure 1). Wild-type and mutant variants of SsChlI were expressed in N. benthaminana with the addition of an N-terminal CTP sequence. See text and Table 1 for details. The binding-sites of SsChlI-specific primers used in RT-PCR analysis are shown as arrows on the schematic of pOY-12. B) Leaves of N. benthamina 12 days post-infiltration. No chlorosis was observed following infiltration with pOY-12. C) Immunoblot analysis of SsChlI protein accumulation following infiltration with pOY-1, pOY-10, pOY-11 and pOY-12 (lanes 1, 10, 11 and 12, respectively). A cross-hybridizing protein recognized by the HA antibody at approximately 100 kDa was used as a loading control. D) RT-PCR analysis of SsChlI transcripts in NT tissues or after infiltration with pOY-11 or pOY-12. Products amplified from an endogenous Ef1α transcript (440 bp) served as a control for cDNA synthesis.