Intracellular plant cell

Cells exposed to excessive levels of salinity have to acquire essential nutrients from a milieu with a preponderance of ions that are potentially toxic and non-essential. In this ionic environment the success of a plant cell will require intracellular tolerance and/or specific acquisition of nutrients essential for normal metabolic functioning. The cell is also exposed to an unfavourable water balance with an absolute requirement to maintain an internal osmotic regulation that favours uptake of water into the cell (Stavarek Rains, 1984 ). 

Ben-Hayyim etal. (1987) demonstrated that cultured citrus cells selected for tolerance to NaCl were most tolerant to polyethylene glycol, followed by NaCl and then CaC. The exposure of the cells to any of these osmotic agents resulted in an increase in intracellular K. The authors concluded that K played a key role in the growth of cells exposed to salt. Other researchers have also suggested that K may play a significant role in the response of plant cells to salinity (Rains, 1972 Croughan, Stavarek Rains, 1978 ... 

Osmotic adjustment by plant cells in response to an increasing saline environment can be mediated by an alteration in intracellular concentrations of both inorganic and organic ions (Wyn Jones, 1980,1984 Aspinall, 1986 Flowers Yeo, 1986 Grumet Hanson, 1986 Moftah Michel, 1987). 

Proteins produced in plant cells can remain within the cell or are secreted into the apoplast via the bulk transport (secretory) pathway. In whole plants, because levels of protein accumulated intracellularly, e. g. using the KDEL sequence to ensure retention in the endoplasmic reticulum, are often higher than when the product is secreted [58], foreign proteins are generally not directed for secretion. However, as protein purification from plant biomass is potentially much more difficult and expensive than protein recovery from culture medium, protein secretion is considered an advantage in tissue culture systems. For economic harvesting from the medium, the protein should be stable once secreted and should accumulate to high levels in the extracellular environment. 

McLean BG, Hempel FD, Zambryski PC. Plant intracellular communication via plasmodesmata. The Plant Cell 1997 9 1043-1054. 

In spite of the variety of appearances of eukaryotic cells, their intracellular structures are essentially the same. Because of their extensive internal membrane structure, however, the problem of precise protein sorting for eukaryotic cells becomes much more difficult than that for bacteria. Figure 4 schematically illustrates this situation. There are various membrane-bound compartments within the cell. Such compartments are called organelles. Besides the plasma membrane, a typical animal cell has the nucleus, the mitochondrion (which has two membranes see Fig. 6), the peroxisome, the ER, the Golgi apparatus, the lysosome, and the endosome, among others. As for the Golgi apparatus, there are more precise distinctions between the cis, medial, and trans cisternae, and the TGN trans Golgi network) (see Fig. 8). In typical plant cells, the chloroplast (which has three membranes see Fig. 7) and the cell wall are added, and the lysosome is replaced with the vacuole. 

At an appropriate intensity level of ultrasound, intracellular microstreaming has been observed inside animal and plant cells with rotation of organelles and eddying motions in vacuoles of plant cells [9]. These effects can produce an increase in the metabolic functions of the cell that could be of use in both biotechnology and microbiology, especially in the areas of biodegradation and fermentation. 

Suzuki T, Fujiwake H, Iwai K (1980) Intracellular localization of capsaicin and its analogues, capsaicinoid, in Capsicum fruit. 1. Microscopic investigation of the structure of the placenta of Capsicum annuum var. annuum cv. Karayatsubusa. Plant Cell Physiol 21 839-853 Ohta Y (1963) Physiological and genetical studies on the pungency of Capsicum IV. Secretory organ, receptacles and distribution of capsaicin in the Capsicum fruits. Jap J Breed 12 179-183... 

Transporters, particularly those carrying nonlipophilic species across biomembranes or model membranes, can be regarded as vectorial catalysts (and are also called carriers, translocators, permeases, pumps, and ports [e.g., symports and antiports]). Many specialized approaches and techniques have been developed to characterize such systems. This is reflected by the fact that there are currently twenty-three volumes in the Methods in Enzymology series (vols. 21,22,52-56,81,88,96-98,125-127,156-157, 171-174, and 191-192) devoted to biomembranes and their constituent proteins. Chapters in each of these volumes will be of interest to those investigating transport kinetics. Other volumes are devoted to ion channels (207), membrane fusion techniques (220 and 221), lipids (14, 35, 71, and 72), plant cell membranes (148), and a volume on the reconstitution of intracellular transport (219). See Ion Pumps... 

The hydrophobic waxy cuticle of plants can inhibit the movement and accessibility of nutrients to bacterial cells. However, biosurfactants produced by the majority of epiphytic Pseudomonas spp. decreases the water tension, enabling relatively free movement across the leaf surface to nutrient sources and natural openings such as stomata. Pseudomonas are also known to release a toxin called syringomycin that can produce holes in the plant cell membrane allowing access to intracellular nutrients without necessarily resulting in disease symptoms (Cao et al.r 2005). 

High hydrostatic pressure (HHP) processes have been used mainly for sauces or seafood and proven effective at reducing microbial populations without adverse effects on product quality (Considine et al., 2008 Brinez et al., 2006). HHP treatment causes bacterial inactivation by damaging the cell membrane, which affects membrane permeability and intracellular enzyme inactivation and possibly ruptures the plant cell wall (Kniel et al.,... 

Nozzolillo, C. and Ishikura, N., An investigation of the intracellular site of anthocyanoplasts using isolated protoplasts and vacuoles. Plant Cell Rep., 7(6), 389, 1988. 

Smith, M.L., Mason, H.S. and Shuler, M.L. (2002). Hepatitis B surface antigen (HbsAg) expression in plant cell cultures kinetics of antigen accumulation in batch culture and its intracellular form. Biotechnol. Bioeng. 80(7) 612-619. 

The biosynthesis of cellulose is less well understood than that of glycogen or starch. As a major component of the plant cell wall, cellulose must be synthesized from intracellular precursors but deposited and assembled outside the plasma membrane. The enzymatic machinery for initiation, elongation, and export of cellulose chains is more complicated than that needed to syn-... 

Further support for the hypothesis that Ca2+ plays a central role in regulating phytoalexin accumulation is provided by experiments in which the turnover of phosphatidylinositol was measured in the plasma membrane of elicitor-treated carrot cells [17]. The carrot cells were first labelled with [3H]myo-inositol and, after the addition of elicitors, acid extracts of the cells were analyzed chromatographically for the production of inositol trisphosphate (IP3). In cells treated with elicitor, the release of radioactive IP3 increased with time and attained a maximum at 3 - 5 min after treatment. Phospholipase activity responsible for the degradation of phosphorylated phosphatidylinositol increased correspondingly. Several reports have shown that IP3 induces rapid release of Ca2+ from intracellular stores in animal cells [18, 19]. Studies on plant cells have also demonstrated that exogenous IP3 releases Ca2+ from microsomal preparations at micromolar concentrations, although only limited... 

Gums and mucilages may be found either in the intracellular pans of plants or as extracellular exudates. Those found within plant cells represent storage material in seeds and roots. They also serve as a water reservoir and as protection for germinating seed. The polysaccharides found as extracellular exudates of higher plants appear to be produced as a result of injury caused by mechanical means or by insects. It has not been well established whether the exudates are formed at the site of the injury. 

A possible function of this intracellular sulfur cycle is to buffer, i.e. to homeostatically regulate, the cysteine concentration of the cells. Irrespective of whether sulfate, cysteine, or sulfur dioxide is available as sulfur source, the intracellular sulfur cycle would allow a plant cell to use as much of these compounds as necessary for growth and development. At the same time, it would give a plant cell the possibility to maintain the cysteine pool at an appropriate concentration by emitting excess sulfur into the atmosphere. Thus, emission of hydrogen sulfide may take place when the influx of sulfur in the form of sulfate, cysteine, or sulfur dioxide exceeds the conversion of these sulfur sources into protein, glutathione, methionine, and other sulfur-containing components of the cell. 

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