Figure 6.

A ZmTLA1-GFP Fusion Protein Was Secreted to the Apoplast Bypassing the Secretory Pathway.

(A) Onion epidermal cell transiently expressing an inducible ZmTLA1-GFP chimeric protein. GFP fluorescence was detected exclusively in the extracellular space and was diffusing within few cell rows.

(B) Onion epidermal cell bombarded with a pUbi:GFP construct. Fluorescence was visible in cytoplasm and nucleus (arrow).

(C) Onion epidermal cells bombarded with a pUbi:ZmES4-GFP construct showed secretion of this extracellular peptide via the secretory pathway. Arrow points toward nucleus surrounded by endoplasmic reticulum and arrowheads toward secretory vesicles.