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Updated: May 31, 2026

Image-Based Methods to Study Membrane Trafficking Events in Stomatal Lineage Cells
Published on: May 12, 2023
Dynamic protein trafficking to the cell wall
Monica De Caroli1, Marcello S Lenucci, Gian-Pietro Di Sansebastiano
1DiSTeBA, Università del Salento, Lecce, Italy.
Abstract:
Recently we have studied the secretion pattern of a pectin methylesterase inhibitor protein (PMEI1) and a polygalacturonase inhibitor protein (PGIP2) in tobacco protoplast using the protein fusions, secGFP-PMEI1 and PGIP2-GFP. Both chimeras reach the cell wall by passing through the endomembrane system but using distinct mechanisms and through a pathway distinguishable from the default sorting of a secreted GFP. After reaching the apoplast, sec-GFP-PMEI1 is stably accumulated in the cell wall, while PGIP2-GFP undergoes endocytic trafficking. Here we describe the final localization of PGIP2-GFP in the vacuole, evidenced by co-localization with the marker Aleu-RFP, and show a graphic elaboration of its sorting pattern. A working model taking into consideration the presence of a regulated apoplast-targeted secretion pathway is proposed.
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