Green plants harvest the energy of Sun in leaves by converting light into chemical bonds sugar molecules, using water from soil and carbon dioxide air. This review provides an overview vascular anatomy physical models that describe long-distance transport minerals root to leaf, and, particular, sugars entire body plant sustaining growth communication throughout even tallest tree.

Sucrose (Suc) transporters belong to a large gene family. The physiological role of SUT1 proteins has been intensively investigated in higher plants, whereas that SUT4 is so far unknown. All three known Suc from potato (Solanum tuberosum), SUT1, SUT2, and SUT4, are colocalized their RNA levels not only follow diurnal rhythm, but also oscillate constant light. Here, we examined the effects transgenic plants on interference (RNAi)-inactivated StSUT4 expression. phenotype StSUT4-RNAi includes...

Suc transporters (SUTs) play a key role in the allocation and partitioning of photosynthetically fixed carbon plants. While function could be assigned to many members SUT family, almost no information is available on their regulation. Here, transcriptional regulation SUTs response various environmental stimuli leaves five dicots (Arabidopsis [Arabidopsis thaliana], soybean [Glycine max], potato [Solanum tuberosum], tomato lycopersicum], poplar [Populus spp.]) four monocots (maize [Zea mays],...

A number of recent studies identified hydrogen sulfide (H2S) as an important signal in plant development and adaptation to environmental stress. H2S has been proven participate ethylene-induced stomatal closure, but how the signaling pathways ethylene interact is still unclear. Here, we reveal controls feedback-regulation biosynthesis tomato (Solanum lycopersicum) under osmotic We found that induced production guard cells. The supply hypotaurine (HT; a scavenger) or DL-pro-pargylglycine...

All multicellular organisms keep a balance between sink and source activities by controlling nutrient transport at strategic positions. In most plants, photosynthetically produced sucrose is the predominant carbon energy source, whose from leaves to organs depends on transporters. model plant Arabidopsis thaliana, of into phloem vascular tissue SUCROSE TRANSPORTER 2 (SUC2) sets rate export leaves, just like SUC2 homologs crop plants. Despite their importance, little known about proteins that...

ABSTRACT Since Münch in the 1920s proposed that sugar transport phloem vascular system is driven by osmotic pressure gradients, his hypothesis has been strongly supported evidence from herbaceous angiosperms. Experimental constraints made it difficult to test this proposal large trees, where distance between source and sink might prove incompatible with hypothesis. Recently, theoretical optimization of mechanism was shown lead surprisingly simple predictions for dimensions sieve elements...

Several recent publications report different subcellular localisation of members the SUT4 subfamily sucrose transporters. The physiological function transporters is still not entirely clarified as down-regulation clade had very effects in rice, poplar and potato. Here, we provide new data on localization Solanaceous StSUT4 protein, further elucidating involvement onset flowering, tuberization shade avoidance syndrome potato plants. Induction early flowering SUT4-inhibited plants correlates...

Yeast cells are protected by a cell wall that plays an important role in the exchange of substances with environment. The structure is dynamic and can adapt to different physiological states or environmental conditions. For investigation morphological changes, selective staining fluorescent dyes valuable tool. Furthermore, used facilitate sub-cellular localization experiments fluorescently-labeled proteins detection yeast non-fungal host tissues. Here, we report Saccharomyces cerevisiae...

In plants, a complex cell wall protects cells and defines their shape. Cellulose fibrils form multilayered network inside the cell-wall matrix that plays direct role in controlling expansion. Resolving structure of this will allow us to comprehend relationship cellulose fibril orientation growth. The fluorescent dye Pontamine Fast Scarlet 4BS (PFS) was shown stain with high specificity could be used visualize bundles walls Arabidopsis root epidermal confocal microscopy. resolution limit...

Abstract The plant sucrose transporter SUT1 from Solanum tuberosum revealed a dramatic redox-dependent increase in transport activity when heterologously expressed Saccharomyces cerevisiae. Plant plasma membrane vesicles do not show any change proton flux across the presence of redox reagents, indicating SUT1-specific effect reagents. Redox-dependent was confirmed electrophysiologically Xenopus laevis oocytes with maize (Zea mays). Localization studies green fluorescent protein fusion...

Abstract An essential step for the distribution of carbon throughout whole plant is loading sugars into phloem in source organs. In many plants, accumulation sieve element‐companion cell (SE‐CC) complex mediated and regulated by active processes. However, poplar other tree species, a passive symplasmic mechanism has been proposed, characterized continuity along pre‐phloem pathway absence sugar SE‐CC complex. A high overall leaf concentration thought to enable diffusion sucrose phloem. this...

In trees, carbohydrates produced in photosynthesizing leaves are transported to roots and other sink organs over distances of up 100 m inside a specialized transport tissue, the phloem. Angiosperm gymnosperm trees have fundamentally different phloem anatomy with respect cell size, shape connectivity. Whether these differences an effect on physiology carbohydrate transport, however, is not clear. A meta-analysis experimental data speed yielded average speeds 56 cm h−1 for angiosperm 22 trees....

During infection, many RNA viruses produce characteristic inclusion bodies that contain both viral and host components. These structures were first described over a century ago originally termed 'X bodies', as their function was not immediately appreciated. Whilst some may represent cytopathic by-products of protein over-accumulation, X-bodies have emerged virus 'factories', quasi-organelles coordinate diverse infection processes such replication, expression, evasion defences, virion...

Uptake of photoassimilates into the leaf phloem is key step in carbon partitioning and transport. Symplasmic apoplasmic loading strategies have been defined different plant taxa based on abundance plasmodesmata between mesophyll phloem. For to occur, an absence a sufficient but not necessary criterion, as passage molecules through might well be blocked or restricted. Here, we present noninvasive, whole-plant approach test symplasmic coupling quantify intercellular flux small using...

Summary In the sieve elements ( SE s) of phloem, carbohydrates are transported throughout whole plant from their site production to sites consumption or storage. structure, especially pore‐rich end walls, has a direct effect on translocation efficiency. Differences in pore size and other features were interpreted as an evolutionary trend towards reduced hydraulic resistance. However, this never been confirmed. Anatomical data 447 species woody angiosperms gymnosperms used for phylogenetic...

Abstract Understanding the molecular mechanisms of abiotic stress responses in plants is instrumental for development climate-resilient crops. Key factors responses, such as proton- pumping pyrophosphatase (AVP1), have been identified, but their function and regulation remain elusive. Here, we explored post-translational AVP1 by ubiquitin-conjugating enzyme UBC34 its relevance salt phosphate starvation Arabidopsis (Arabidopsis thaliana). Through vitro vivo assays, established that interacts...

The phloem plays a central role in transporting resources and signalling molecules from fully expanded leaves to provide precursors for, direct development of, heterotrophic organs located throughout the plant body. We review recent advances understanding mechanisms regulating loading unloading of into, from, network; highlight unresolved questions regarding physiological significance vast array proteins RNAs found saps; evaluate proposed structure/function relationships considered account...

The lemnoidae, commonly called duckweeds, are a group of small, rapidly growing aquatic plants that play an important role in pond ecosystems and used biotechnological remediation applications. While duckweeds feature phloem tissue fronds roots. To gain insight on duckweed function, we investigated how sugar is loaded into the sieve elements giant Spirodela polyrhiza. Genomes S. polyrhiza three other do not genes for sucrose transporters typically associated with active apoplastic loading....