Trafficking of Plant Vacuolar Invertases: From a Membrane-Anchored to a Soluble Status. Understanding Sorting Information in Their Complex N-Terminal Motifs

摘要: Vacuolar invertases (VIs) are highly expressed in young tissues and organs. They may have a substantial regulatory influence on whole-plant metabolism as well photosynthetic efficiency. Therefore, they emerging potentially interesting biotechnological targets to increase plant biomass production, especially under stress. On the one hand, VIs known soluble extractable proteins. other contain complex N-terminal propeptide (NTPP) regions with basic region (BR) transmembrane domain (TMD). Here we analyzed depth Arabidopsis thaliana VI2 (AtVI2) NTPP by mutagenesis. It was found that correct sorting lytic vacuole (LV) depends presence of intact dileucine (SSDALLPIS), BR (RRRR) TMD motifs. AtVI2 remains inserted into membranes its way LV, classical pathway (endoplasmic reticulum→Golgi→LV) is followed. However, our data suggest might follow an alternative, adaptor protein 3 (AP3)-dependent route well. Membrane-anchored transport direct recognition motif evolved simple more efficient mechanism compared vacuolar receptor 1/binding 80 kDa (VSR1/BP80)-dependent followed those proteins travel