Tobacco leaf cell

Glucuronomannans. Most glucuronomaimans occur as components of certain plant gums and are characterized by the presence of an 0-(P -D-glucurono-pyranosyl)-(1 2)-D-maimopyranosyl linkage ia the molecule (65). Less complex glucuronomaimans are found in the tissues of bracken Pteridium aquilinum) and in tobacco leaf cells where they may be part of the cultured cell wall (132) and exude into the medium in which the cells are grown (133). 

Boffey, S.A. and Northcote, D.H. (1975) Pectin synthesis during the wall regeneration of plasmolysed tobacco leaf cells. BiochemJ. 150 433-440. 

FIGURE 1.12 The nucleus of a tobacco leaf cell (magnified 15,000x). 

Useful progress has been made in the genetics of GAs, ABA and, more recently, ethylene [11]. However, relatively few mutations have been reported involving auxins or cytokinins. Both recessive and dominant mutants have been isolated with increased resistance to synthetic auxins [8, 14, 16], and two mutants have been described with significantly altered levels of lAA or lAA conjugates [20, 22]. Mutations have been reported that affect the cytokinin requirement of tobacco leaf cells in culture [15], and cytokinin resistance and production in the moss Phys-comitrella patens [23]. 

Human papilloma virus (HPV) type 16 oncoprotein E7 Potato virus X in tobacco leaf (complete reading frame) Immunogenic in mice when administered parenterally. Mice protected moderately when challenged with surrogate (C3 cells). 100... 

Figures 3A and 3B show low and high magnification images of the noncutinized lower epidermal cell surfaces in a senescent Coker 319 tobacco leaf. The junctions between four different epidermal cells can be seen in Figure 3A. Also, multiple layers of pectin were evident on these lower epidermal cells, but were not present on the epidermal surface of...

Figure 2A. Freeze-dried, Pt/C replicated, untreated noncutinized lower epidermal cell surface of a fresh, green Coker 319 tobacco leaf. (Bar = 1,000A.)...

Chinese hamster ovary cells. The number of aberrant metaphases increased in cultures with 15 mL tobacco extract per milliliter of growth media Water extract of the dried leaf, administered to mice at a dose of 9.40 g/kg, 6 days a week for 10 months, was active on bone marrow. A combination of Piper betle, Areca catechu, and Nicotiana tabacum was used . Seed, administered orally to adults with oral cancer and oral submucosal fibrosis and to healthy chewers, was active. An average of 6 quids of tobacco leaf, Areca nuts, and lime were chewed daily T . ... 

Finally, one also has to consider, that hydrogenation of live cells creates un unnatural composition and physical state (increased rigidity) of the membranes. In case the cells survive this treatment, they mobilize all their reserves to restore the original conditions, optimal for life at the given temperature, pressure, culture medium, etc. Detection of de novo synthetized unsaturated lipids during hydrogenation of protoplasts from tobacco leaf (Nicotiana plumbaginifolid) proved that such compensation of unfavourable outside effects can follow the stress very fast (immediately) and can be very effective [214],... 

The role of active oxygen and the resulting free radicals from phytoalexins may be important aspects in the defense response. For example, the production of H2O2 (2A) and 02 (33) in response to a pathogen derived elicitor has been confirmed in soybean cell suspension cultures. Tobacco leaf disc infected with... 

Incompatible strains of Pseudomonas pisi appear to be immobilised in tobacco leaf tissue by adherence and this is followed by engulfment by cuticle-like material secreted by plant cells. The compatible tobacco pathogen P. tobaci does not produce such a response. Similarly the saprophytic bacterium P. putida adheres to and becomes enveloped by cells in the bean leaf, while a compatible pathogen P. phaseolicola shows no response. Actual physical contact between the bacterium and plant cell walls is required for the hypersensitive response in pepper plants induced by X, vesicatoria. 

These are the facts which point to RNA being the template on which the synthesis of proteins takes place. Another confirmation has been brought by experiments showing that the isolated nucleic acid of tobacco mosaic virus can introduce the disease into a leaf cell as well as the whole nucleoprotein of the virus. 

Anderson J D et al 1982 Induction of ethylene biosynthesis in tobacco leaf-disks by cell-wall digesting enzymes. Biochem/Biophysiol Rev 107 588-596... 

Molecular species Soya beans Potato tissue tuber microsomes leaves Tobacco microsomes cells leaf Pea microsomes Apple embryos... 

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