Protein synthesis in plants

These findings started a tremendous wave of research interest (a fashion) into the potential role of cytokinins in nucleic acid synthesis (and hence the control of protein synthesis) in plants. Looking back on those years of the early 1960s, the... 

Higgins, T. J. V. Zwar, J. A. Jacobsen, J. V. Hormonal control of the level of translatable mRNA for barley aleurone layers. In Nucleic Acids and Protein Synthesis in Plants, Ed. J. H. Well L. Bogorad, Paris ... 

Ries et al. (1974) observed an increase in nitrate and water uptake by a barley culture grown ip nutrient solution with 10 mole/dm simazine. After 12 days the barley contained 22% more protein than the controls. When treated with 10" mole/dm simazine, barley was of the same height as the control plant after 12 days, but contained 26% more protein. Atrazine increased the growth of the embrional axis of bean and enhanced its protein synthesis. These investigations indicate that sublethal doses of simazine and atrazine stimulate protein synthesis in plants. 

Tymonko and Foy (1978) found in soybean an inhibition of leucine incorporation and a general disturbance of protein synthesis in plants treated with glyphosate. 

Our understanding of the mechanism of protein synthesis in plants comes mainly from studies on cell-free (in vitro) systems derived from seeds—by far the most popular material has been the isolated wheat embryo and commercially-produced wheat germ. 

Compared to animal tissues and bacteria, very little work has been done in tiie last 10 years on protein synthesis in plants. There are, however, a few experiments to show that the incorporation of labeled amino acids into plant proteins follows a path very similar to that just described for aninfiftl cells. 

D. Boulter. Protein synthesis in plants. Arm. Rev. Plant Physiol, 21 91-114, 1970. 

Ben-Zioni, A., Itai, C. Vaadia, Y. (1967). Water and salt stresses, kinetin and protein synthesis in tobacco leaves. Plant Physiology, 42, 361-5. 

Drought also has a profound effect on protein synthesis. In many plant tissues, a reduced water potential causes a reduction of total protein synthesis and a rapid dissociation of polyribosomes. The latter has been shown not to be the consequence of increase in ribonuclease activity (Hsiao, 1973 Dhindsa Bewley, 1976). For a specific protein, Jacobsen, Hanson Chandler (1986) have shown in barley leaves that water stress enhances the synthesis of one of the a-amylase isozymes. Using a cDNA probe they found that water-stressed leaves contained much more a-amylase mRNA than unstressed plants. 

Anaerobic treatment results in a drastic alteration in the pattern of protein synthesis in maize seedlings (Sachs, Freeling Okimoto, 1980). Pre-existing (aerobic) protein synthesis is repressed while selective synthesis of new polypeptides is initiated (Sachs et al., 1980). This is most likely a plant s natural response to flooding. 

Hurkman, W.J. Tanaka, C.K. (1987). The effects of salt on the pattern of protein synthesis in barley roots. Plant Physiology, 83, 517-24. 

Group 2 includes some 80 sesquiterpene trichothecenes, which are particularly associated with fungi belonging to the group Fusarium. Fusarium species are widely known both as plant pathogens and contaminants of stored foods snch as maize. Trichothecenes are strong inhibitors of protein synthesis in mammalian cells. There have been many incidents of poisoning of farm animals cansed by contamination of their food by these componnds. 

Mishra, N.P., Mishra, R.K. and Singhal, C.S. (1993). Changes in the activities of antioxidant enzymes during exposure of intact wheat leaves to strong visible light at different temperatures in the presence of protein synthesis inhibitors. Plant Physiology 102 903-910. 

Ribosome inactivating cytotoxic protein that irreversibly inhibits protein synthesis in cells, causing cell death. It is a solid obtained from the mistletoe plant (Viscum album). 

Kaderbhai, M.A., R.B. Beechey, andN. Kaderbhai. 1989. Protein synthesis in isolated castor bean mitochondria is stimulated by cyanide. Plant Physiol. 89 669-673. 

Intermediate-level review of the genes and proteins involved in starch synthesis in plant tubers. 

An open question is whether auxin stimulates wall loosening by acting at the level of gene transcription. Auxin certainly stimulates the rate of RNA synthesis in plant section,454-456 isolated nuclei,457-459 and chromatin,457,460 and new protein species appear after treatment of intact tissues with the hormone.461-463 However, the findings of Haschemeyer464 and Evans and Ray465 strongly indicated that the induction of cell-wall exten-... 

Meza-Basso, L., Alberdi, M., Raynal, M., Ferrero-Cadinanos, M.-L. Delseny, M. (1986). Changes in protein synthesis in rapeseed Bras-sica napus) seedlings during a low temperature treatment. Plant Physiology 82, 733-8. 

Robertson, A.J., Gusta, L.V., Reaney, M.J.T. Ishikawa, M. (1987). Protein synthesis in bromegrass (Bromus inermis Leyss) cultured cells during the induction of frost tolerance by abscisic acid or low temperature. Plant Physiology 84, 1331-6. 

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