Arabinogalactan Proteins and the Extracellular Matrix of Charophytes: A Sticky Business

摘要: Charophytes represent the group of green algae whose ancestors invaded land and ultimately gave rise to plants 450 million years ago. While Zygnematophyceae are believed be direct sister lineage embryophytes, different members this (Penium, Spirogyra, Zygnema) advanced thallus forming Coleochaete as well sarcinoid basal streptophyte Chlorokybus were investigated concerning their vegetative extracellular matrix (ECM) properties. Many taxa exhibit adhesion phenomena that critical for affixing a substrate or keeping cells together in thallus, however, there is great variety possible reactions e.g., wounding. In study an analysis mechanisms revealed arabinogalactan proteins (AGPs) most likely key molecules. Through use monoclonal antibodies (JIM13) Yariv reagent, AGPs located cell surface sheaths walls parts focal zones on substrates including wound induced rhizoid formation. JIM5, detecting highly methyl-esterfied homoglacturonan JIM8, antibody AGP glycan LM6 arabinans also tested colocalization was found several examples (e.g., suggesting interplay between these components. have been described perform both, thalli filamentous forms. These findings enable broader evolutionary understanding function charophyte algae.