Role of membrane transport in phloem translocation of assimilates and water
By J. Patrick, Wen‐Hao Zhang, Steve Tyerman, C. Offler, N. A. Walker. 2001
123 citations recorded by the source corpus.
Most growth and storage organs (sinks) of higher plants import assimilates in solution by bulk flow through the phloem, driven by differences in hydrostatic pressure. These differences in pressure, located between the ends of the interconnecting phloem path, are generated by osmotic water movement, driven in turn by membrane transport of solutes. Sucrose, amino-nitrogen compounds and potassium represent the osmotically important solutes found in phloem contents of most species. Phloem loading and unloading events of these assimilate species play central roles in determining phloem translocation rates and partitioning of assimilates and water. Depending on plant species, leaf vein order and sink type, phloem loading and unloading may follow apoplasmic or symplasmic routes. Irrespective of the cellular pathway followed, assimilates are transported across plasma and organellar membranes. Aquaporins, amino-nitrogen transporters, sucrose transporters and potassium channels have been detected in key sites along the source-phloem-sink transport pathway. Reverse genetics has demonstrated that sucrose/proton symporters are important in transport events necessary for phloem loading in Solanaceous plant species. Drawing on circumstantial evidence, we review possible functions the remaining membrane transporters and channels may serve in driving phloem translocation of assimilates and water from source to sink.
Subfields: Plant Science
View Paper: https://www.semanticscholar.org/paper/267ddcc6c933d80b745ee9fcc3105c232934d4da
Citations in the corpus
- Phloem loading and unloading of sugars and amino acids (2003, unknown): “Filial pool sizes of sucrose and amino acids are candidates to function as signals because these change in response to altered rates of solute delivery and storage product formation and are known to regulate symporter gene expression through de-repression (Patrick et al. 2001).”
- Comprehending crystalline β-carotene accumulation by comparing engineered cell models and the natural carotenoid-rich system of citrus (2011, unknown): “These genes may be involved in controlling water dynamics related to changing source/sink status during the night (Patrick et al., 2001).”