Nejvíce citovaný článek - PubMed ID 34470819
Plasma membrane phospholipid signature recruits the plant exocyst complex via the EXO70A1 subunit
Once regarded as mere membrane building blocks, lipids are now recognized as diverse and intricate players that mold the functions, identities, and responses of cellular membranes. Although the interactions of lipids with integral and peripheral membrane proteins are crucial for their localization, activity, and function, how proteins bind lipids is still far from being thoroughly explored. Describing and characterizing these dynamic protein-lipid interactions is thus essential to understanding the membrane-associated processes. Here we review the current range of experimental techniques employed to study plant protein-lipid interactions, integrating various methods. We summarize the principles, advantages, and limitations of classical in vitro biochemical approaches, including protein-lipid overlays and various liposome binding assays, and complement them with in vivo microscopic techniques centered around the use of genetically encoded lipid sensors and pharmacological or genetic membrane lipid manipulation tools. We also highlight several emerging techniques still awaiting their advancement into plant membrane research and emphasize the need to use complementary experimental strategies as key for elucidating the mechanistic roles of protein-lipid interactions in plant cell biology.
- Klíčová slova
- Genetically encoded biosensors, lipid manipulation, membrane lipid imaging, microscopy, peripheral membrane proteins, protein–lipid interactions,
- MeSH
- buněčná membrána * metabolismus MeSH
- membránové lipidy metabolismus MeSH
- membránové proteiny metabolismus MeSH
- rostlinné proteiny * metabolismus MeSH
- rostliny metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- membránové lipidy MeSH
- membránové proteiny MeSH
- rostlinné proteiny * MeSH
Exocyst component of 70-kDa (EXO70) proteins are constituents of the exocyst complex implicated in vesicle tethering during exocytosis. MILDEW RESISTANCE LOCUS O (MLO) proteins are plant-specific calcium channels and some MLO isoforms enable fungal powdery mildew pathogenesis. We here detected an unexpected phenotypic overlap of Arabidopsis thaliana exo70H4 and mlo2 mlo6 mlo12 triple mutant plants regarding the biogenesis of leaf trichome secondary cell walls. Biochemical and Fourier transform infrared spectroscopic analyses corroborated deficiencies in the composition of trichome cell walls in these mutants. Transgenic lines expressing fluorophore-tagged EXO70H4 and MLO exhibited extensive colocalization of these proteins. Furthermore, mCherry-EXO70H4 mislocalized in trichomes of the mlo triple mutant and, vice versa, MLO6-GFP mislocalized in trichomes of the exo70H4 mutant. Expression of GFP-marked PMR4 callose synthase, a known cargo of EXO70H4-dependent exocytosis, revealed reduced cell wall delivery of GFP-PMR4 in trichomes of mlo triple mutant plants. In vivo protein-protein interaction assays in plant and yeast cells uncovered isoform-preferential interactions between EXO70.2 subfamily members and MLO proteins. Finally, exo70H4 and mlo6 mutants, when combined, showed synergistically enhanced resistance to powdery mildew attack. Taken together, our data point to an isoform-specific interplay of EXO70 and MLO proteins in the modulation of trichome cell wall biogenesis and powdery mildew susceptibility.
- MeSH
- Arabidopsis * metabolismus MeSH
- buněčná stěna metabolismus MeSH
- nemoci rostlin mikrobiologie MeSH
- odolnost vůči nemocem genetika MeSH
- protein - isoformy genetika metabolismus MeSH
- proteiny huseníčku * genetika metabolismus MeSH
- rostlinné proteiny metabolismus MeSH
- trichomy genetika metabolismus MeSH
- vezikulární transportní proteiny metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- EXO70H4 protein, Arabidopsis MeSH Prohlížeč
- protein - isoformy MeSH
- proteiny huseníčku * MeSH
- rostlinné proteiny MeSH
- vezikulární transportní proteiny MeSH
Extracellular vesicles are small membrane particles (30-1000 nm) released by Bacteria, Eukaryotes and Archaea. They have been shown to play an important role in intracellular and intercellular communication, within and between kingdoms via transport of bioactive molecules. Thus, they can be involved in altering gene expression and regulation of physiological and pathological processes of the recipient. Their unique properties make extracellular vesicles a perfect candidate vector for targeted drug delivery or a biomarker. For a long time, animal and mainly mammal extracellular vesicles have been used in research. But for plants, there had been speculations about the existence of nanovesicles due to the presence of a cell wall. Today, awareness of plant extracellular vesicles is on the rise and their research has proved they have various functions, such as protein secretion, transport of bioactive molecules or defense against pathogens. Further potential of plant extracellular vesicles is stressed in this review.
- MeSH
- Bacteria MeSH
- biologické markery metabolismus MeSH
- extracelulární vezikuly * metabolismus MeSH
- lékové transportní systémy MeSH
- lidé MeSH
- mezibuněčná komunikace MeSH
- savci MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- biologické markery MeSH
Localized delivery of plasma-membrane and cell-wall components is a crucial process for plant cell growth. One of the regulators of secretory-vesicle targeting is the exocyst tethering complex. The exocyst mediates first interaction between transport vesicles and the target membrane before their fusion is performed by SNARE proteins. In land plants, genes encoding the EXO70 exocyst subunit underwent an extreme proliferation with 23 paralogs present in the Arabidopsis (Arabidopsis thaliana) genome. These paralogs often acquired specialized functions during evolution. Here, we analyzed functional divergence of selected EXO70 paralogs in Arabidopsis. Performing a systematic cross-complementation analysis of exo70a1 and exo70b1 mutants, we found that EXO70A1 was functionally substituted only by its closest paralog, EXO70A2. In contrast, none of the EXO70 isoforms tested were able to substitute EXO70B1, including its closest relative, EXO70B2, pointing to a unique function of this isoform. The presented results document a high degree of functional specialization within the EXO70 gene family in land plants.
- Klíčová slova
- Arabidopsis, EXO70, EXO70A1, EXO70B1, exocyst complex, polar exocytosis,
- MeSH
- Arabidopsis genetika růst a vývoj metabolismus MeSH
- buněčná membrána metabolismus MeSH
- exocytóza MeSH
- proteiny huseníčku genetika metabolismus MeSH
- regulace genové exprese u rostlin MeSH
- transportní vezikuly metabolismus MeSH
- vezikulární transportní proteiny genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- proteiny huseníčku MeSH
- vezikulární transportní proteiny MeSH