The Nβ motif is responsible for NaTrxh secretion. (A) An NaTrxh scheme indicating its N- and C-terminal extensions. The N-terminus was subdivided into two regions: Nα (red) and Nβ (cyan). The C-terminus (green). (B) Transient expression of the different NaTrxh mutants fused to GFP in onion epidermal cells. (B-1) (B-2) Full-length NaTrxh. (B-3) (B-4) NaTrxhΔNα. (B-5) (B-6) NaTrxhΔNβ. (B-7) (B-8) NaTrxhΔNαβ. (B-9) (B-10) Nβ motif (Ala-17 to Pro-27) directly fused to GFP. (B-11) (B-12) NaTrxhΔCOO. (B-1) (B-3) (B-5) (B-7) (B-9) (B-11) GFP fluorescence. (B-2) (B-4) (B-6) (B-8) (B-10) (B12). Bright fields merged with flourescence images. The cells were plasmolyzed with 1 M NaCl before confocal observation. CW: cell wall; M. plasma membrane. Scale bars = 50 μm.