Publications by authors named "Steve Tyerman"

Plant aquaporins (AQPs) were initially described as a family of membrane-localized proteins exclusively facilitating water transport. Subsequently, sub-sets of plant AQPs have exhibited diverse functionalities beyond water transport. The aquaporin AtPIP2;1, an abundant Plasma membrane Intrinsic Protein in Arabidopsis thaliana, can transport water but also CO, HO and monovalent cations under certain conditions.

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A fundamental limitation of photosynthetic carbon fixation is the availability of CO. In C plants, primary carboxylation occurs in mesophyll cytosol, and little is known about the role of CO diffusion in facilitating C photosynthesis. We have examined the expression, localization, and functional role of selected plasma membrane intrinsic aquaporins (PIPs) from (foxtail millet) and discovered that SiPIP2;7 is CO-permeable.

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Chloroplast retrograde signaling networks are vital for chloroplast biogenesis, operation, and signaling, including excess light and drought stress signaling. To date, retrograde signaling has been considered in the context of land plant adaptation, but not regarding the origin and evolution of signaling cascades linking chloroplast function to stomatal regulation. We show that key elements of the chloroplast retrograde signaling process, the nucleotide phosphatase (SAL1) and 3'-phosphoadenosine-5'-phosphate (PAP) metabolism, evolved in streptophyte algae-the algal ancestors of land plants.

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The aquaporin AtPIP2;1 is an abundant plasma membrane intrinsic protein in Arabidopsis thaliana that is implicated in stomatal closure, and is highly expressed in plasma membranes of root epidermal cells. When expressed in Xenopus laevis oocytes, AtPIP2;1 increased water permeability and induced a non-selective cation conductance mainly associated with Na . A mutation in the water pore, G103W, prevented both the ionic conductance and water permeability of PIP2;1.

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Leaf area index (LAI) and plant area index (PAI) are common and important biophysical parameters used to estimate agronomical variables such as canopy growth, light interception and water requirements of plants and trees. LAI can be either measured directly using destructive methods or indirectly using dedicated and expensive instrumentation, both of which require a high level of know-how to operate equipment, handle data and interpret results. Recently, a novel smartphone and tablet PC application, VitiCanopy, has been developed by a group of researchers from the University of Adelaide and the University of Melbourne, to estimate grapevine canopy size (LAI and PAI), canopy porosity, canopy cover and clumping index.

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• Proteins possessing the SPX domain are found in several proteins involved in inorganic phosphate (Pi) transport and signalling in yeast and plants. Although the functions of several SPX-domain protein subfamilies have recently been uncovered, the role of the SPX-MFS subfamily is still unclear. • Using quantitative RT-PCR analysis, we studied the regulation of SPX-MFS gene expression by the central regulator, OsPHR2 and Pi starvation.

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TaALMT1 encodes a putative transport protein associated with Al(3+)-activated efflux of malate from wheat root apices. We expressed TaALMT1 in Nicotiana tabacum L. suspension cells and conducted a detailed functional analysis.

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Water sources of Eucalyptus camaldulensis Dehn. trees were investigated on a semiarid floodplain in south-eastern Australia. The trees investigated ranged in distance from 0.

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