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Microtubules, the major components of cytoskeleton, are involved in various fundamental biological processes in plants. Recent studies in mammalian cells have revealed the importance of microtubule cytoskeleton in autophagy. However, little is known about the roles of microtubules in plant
The expression of the starch-synthase gene was studied by in situ RNA hybridization at different stages of pollen development in tobacco (Nicotiana tabacum L.). By means of Northern blot analysis we demonstrated that a potato (Solarium tuberosum L.) gene was homologous to its tobacco counterpart,
Tobacco plants (Nicotiana tabacum L.) transformed with sense and antisense constructs of a cDNA encoding the tobacco phosphate-triose phosphate-3-phosphoglycerate translocator (phosphate translocator) were shown to contain altered amounts of phosphate translocator mRNA and protein. Phosphate
Thioredoxin (Trx) f and NADPH-dependent Trx reductase C (NTRC) have both been proposed as major redox regulators of starch metabolism in chloroplasts. However, little is known regarding the specific role of each protein in this complex mechanism. To shed light on this point, tobacco plants that were
By phase microscopic observation of living palisade parenchyma cells in sections of Nicotiana excelsior leaves from plants previously placed in the dark for 72 hours, 30 to 45 minutes of light is found to induce mitochondria to remain stationary within the concavity of the chloroplasts and become
In cultured Bright Yellow-2 (BY-2) tobacco (Nicotiana tabacum) cells, the depletion of auxin (2,4-dichlorophenoxyacetic acid) in the culture medium induces the accumulation of starch. This is accelerated by the addition of cytokinin (benzyladenine). Light and electron microscopic observations
The aim of this work was to study the effect of elevated fructose-2,6-bisphosphate (Fru-2,6-bisP) levels on carbohydrate metabolism in leaves in the dark. In transgenic tobacco (Nicotiana tabacum L.) lines containing mammalian 6-phosphofructo-2-kinase activity there is an inverse relationship
Carbon isotope (13C) fractionations occurring during and after photosynthetic CO2 fixation shape the carbon isotope composition (δ13C) of plant material and respired CO2. However, responses of 13C fractionations to diel variation in starch metabolism in the leaf are not fully understood. Here we
Chimaeric genes of promoter sequences from the potato gene encoding granule-bound starch synthase (GBSS) and the beta-glucoronidase (GUS) reporter gene were used to study GBSS expression and regulation. Analysis of stable transformants revealed that a GBSS promoter sequence of 0.4 kb was sufficient
Gravitropism was studied in seedlings of Nicotiana sylvestris Speg. et Comes wild-type (WT) and mutant NS 458 which has a defective plastid phosphoglucomutase (EC 2.7.5.1.). Starch was greatly reduced in NS 458 compared to the WT, but small amounts of starch were detected in rootcap columella cells
In BY-2 cultured tobacco cells (Nicotiana tabacum L.), depletion of 2,4-dichlorophenoxyacetic acid (2,4-D) and addition of benzyladenine (BA) caused amyloplast formation, a decrease in cell multiplication, and an increase in cell size. These changes were primarily triggered by the depletion of
In cultured Bright Yellow-2 tobacco (Nicotiana tabacum) cells, the depletion of 2,4-dichlorophenoxyacetic acid (2,4-D) in the culture medium induces amyloplast development. This differentiation also includes a decrease in cell multiplication, and an increase in cell size. These changes were
In plants, the G2/M control of cell cycle remains an elusive issue as doubts persist about activatory dephosphorylation--in other eukaryotes provided by CDC25 phosphatase and serving as a final all-or-nothing mitosis regulator. We report on the effects of tobacco (Nicotiana tabacum L., cv. Samsun)
BACKGROUND
Agrobacterium tumefaciens-based transient assays have become a common tool for answering questions related to protein localization and gene expression in a cellular context. The use of these assays assumes that the transiently transformed cells are observed under relatively authentic
Mounting evidence suggests that microtubules play important roles in several aspects of autophagy in mammalian cells, such as autophagosome biogenesis, autophagosome trafficking and autolysosome formation. However, little research attention has been paid to the engagement of microtubules in plant