Leathanach 1 ó 19 torthaí
The key enzymes of photosynthetic carbon assimilation in C4 plants have evolved from C3 isoforms which were present in the C3 ancestral species. We are interested in the molecular changes responsible for the novel expression pattern of C4 genes and are focussing on phosphoenolpyruvate carboxylase
Transgenic tobacco (Nicotiana tabacum L.) plants with decreased and increased transport capacities of the chloroplast triose phosphate/phosphate translocator (TPT) were used to study the control the TPT exerts on the flux of starch and sucrose biosynthesis, as well as CO2 assimilation, respiration
To improve the efficiency of CO(2) fixation in C(3) photosynthesis, C(4)-cycle genes were overexpressed in potato and tobacco plants either individually or in combination. Overexpression of the phosphoenolpyruvate carboxylase (PEPC) gene (ppc) from Corynebacterium glutamicum (cppc) or from potato
The physiological properties of transgenic tobacco plants (Nicotiana tabacum L.) with decreased or increased transport capacities of the chloroplast triose phosphate/phosphate translocator (TPT) were compared in order to investigate the extent to which the TPT controls metabolic fluxes in wild-type
Flaveria bidentis (L.) Kuntze, a C4 dicot, was genetically transformed with a construct encoding the mature form of tobacco (Nicotiana tabacum L.) carbonic anhydrase (CA) under the control of a strong constitutive promoter. Expression of the tobacco CA was detected in transformant whole-leaf and
Phosphoenolpyruvate carboxylase (PEPC) is a central enzyme of C4 and CAM photosynthesis but plants, in addition, contain various non-photosynthetic isoforms with characteristic and variable functions. The partial sequence and a detailed expression analysis of the PpcB and PpcC genes which encode
Three to four families of nuclear genes encode different isoforms of phosphoenolpyruvate (PEP) carboxylase (PEPC): C4-specific, C3 or etiolated, CAM and root forms. C4 leaf PEPC is encoded by a single gene (ppc) in sorghum and maize, but multiple genes in the C4-dicot Flaveria trinervia. Selective
Rubisco activase functions to promote and maintain the catalytic activity of Rubisco. Studies with the activase-lacking Arabidopsis rca mutant (Salvucci et al. Photosynth Res 7:193-201, 1985; Salvucci et al. Plant Physiol 80:655-659, 1986), antisense activase tobacco, Arabidopsis and Flaveria
Improving global yields of important agricultural crops is a complex challenge. Enhancing yield and resource use by engineering improvements to photosynthetic carbon assimilation is one potential solution. During the last 40 million years C(4) photosynthesis has evolved multiple times, enabling
Carbon isotope discrimination (Δ) during C3 photosynthesis is dominated by the fractionation occurring during CO2-fixation by the enzyme Rubisco. While knowing the fractionation by enzymes is pivotal to fully understanding plant carbon metabolism, little is known about variation in the
Many aspects of photosynthetic gene expression are posttranscriptionally regulated in C4 plants. To determine if RbcS mRNA untranslated regions (UTRs) in themselves could confer any characteristic C4 expression patterns, 5'- and 3'-UTRs of AhRbcS1 mRNA from the C4 dicot amaranth were linked to a
Phosphoenolpyruvate carboxylase (PEPC) genes from Corynebacterium glutamicum (cppc), Escherichia coli (eppc) or Flaveria trinervia (fppc) were transferred to Solanum tuberosum. Plant regenerants producing foreign PEPC were identified by Western blot analysis. Maximum PEPC activities measured in eppc
In Flaveria pringlei, a C3 plant, P protein of the glycine-cleavage system is encoded by a small gene family consisting of at least five transcriptionally active genes. We have cloned and sequenced two of these genes, gdcsPA and gdcsPB, and provide the first detailed report on the complete structure
The efficient functioning of C4 photosynthesis requires the strict compartmentation of a suite of enzymes in either mesophyll or bundle sheath cells. To determine the mechanism controlling bundle sheath cell-specific expression of the NADP-malic enzyme, we made a set of chimeric constructs using the
An indirect immunofluorescence technique was used to determine the intercellular compartmentation of phosphoenolpyruvate (PEP) carboxylase and ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) proteins in leaves of five species of Flaveria, F. brownii A.M. Powell (C4), F. cronquistii A.M.