Cloning of plants

Cloning. Asexual propagation (cloning) of plants ordinarily occurs by virture of the ability of embryonic meristematic tissue to differentiate into roots and shoots. If isolated phloem cells or other more differentiated cells are cultured, the result is often the formation of a callus, a dedifferentiated mass of cells somewhat reminiscent of embryonic cells. Under proper conditions, e.g., in a coconut milk culture and in the presence of the correct auxin-to-cytokinin ratio, some carrot root phloem cells revert to embyronic cells and develop into intact plants.99 This experiment provided proof that the differentiated carrot phloem cells... 

HASHIMOTO, T., TAMAKI, K., SUZUKI, K.I., YAMADA, Y Molecular cloning of plant spermidine synthases. Plant Cell Physiol., 1998,39, 73-79. 

It has been known for some time that tolerance towards high levels of both essential and toxic metals in a local soil environment is exhibited by species and clones of plants that colonize such sites. Tolerance is generally achieved by a combination of exclusion and poor uptake and translocation. Some species can accumulate large quantities of metals in their leaves and shoots at potentially toxic levels, but without any harmful effects. These metal-tolerant species have been used in attempts to reclaim and recolonize metal-contaminated wastelands. More recently such species have attracted the attention of inorganic chemists. There is abundant evidence that the high metal levels are associated with carboxylic acids, particularly with nickel-tolerant species such as Allysum bertolonii. The main carboxylic acids implicated are citric, mahc and malonic acids (see refs. 30 and 31 and literature cited therein). Complexation of zinc by malic and oxalic acids has been reported in the zinc-tolerant Agrostis tenuis and oxalic acid complexation of chromium in the chromium-accumulator species Leptospermum scoparium ... 

The first small steps have been made, but the field of bioconversion still contains numerous possibilities yet to be explored. Cloning of plant genes into microorganisms could be of interest, particularly in the case that cofactors are required. Bioconversions with plant enzymes seem to offer great potential for biotechnologiczil applications. 

Calgene (Thompson, G.A. and Knauf, V.C.) (1991a) Cloning of plant desaturase cDNA and its expression in transgenic plants. World Patent 91 13,972. 

Bach TJ, Wettstein A, Boronat A, Ferrer A, Enjuto M, Gruissem W, Narita JO. Properties and molecular cloning of plant HMG-CoA reductase. In Patterson GW, Nes WD, editors. Physiology and Biochemistry of Sterols, American Oils Chemists Sociandy, Champaign, Illinois, 1991 29-49 ... 

Hanzawa Y, Imai A, Michael AJ, Komeda Y, Takahashi T (2002) Characterization of the spermidine synthase-related gene family in Arabidopsis thaliana. FEBS Lett 527 176-180 Hardtke CS, Berleth T (1998) The Arabidopsis gene MONOPTEROS encodes a transcription factor mediating embryo axis formation and vascular development. EMBO J 17 1405-1411 Hashimoto T, TamaM K, Suzuki K, Yamada Y (1998) Molecular cloning of plant spermidine synthases. Plant CeU Physiol 39 73-79... 

At present, cell culture work is done mostly by hand by horticulturists in large greenhouses (Plate 3). Chemical engineers could greatly increase the usefulness of this method of plant propagation by developing efficient automated processes for producing plants from cloned cells. 

ISAACSON T, RONEN G, ZAMIR D and HIRSCHBERG J (2002) Cloning of tangerine from tomato reveals a carotenoid isomerase essential for production of 3-carotene and xanthophyUs in plants . Plant Cell, 14, 333-42. 

RONEN G, CARMEL-GOREN L, ZAMIR D and HIRSCHBERG J (2000) An alternative pathway to 13-carotene formation in plant chromoplast discovered by map-based cloning of beta and old-gold color mutations in tomato , Proc Natl Acad Sci, 97, 11102-7. 

Hortensteiner, P. et ah. Chlorophyll breakdown in Chlorella protothecoides characterization of degreening and cloning of degreening-related genes. Plant Mol. Biol., 42, 439, 2000. 

Bouvier, F. et ah, Xanthophyll biosynthesis in chromoplasts isolation and molecular cloning of an enzyme catalyzing the conversion of 5,6-epoxycarotenoid into ketocar-otenoid. Plant J. 6, 45, 1994. 

Buckner, B. et al.. Cloning of the yl locus of maize, a gene involved in the biosynthesis of carotenoids, Plant Cell 2, 867, 1990. 

Harriman,R.W.,Tieman,D.M and Handa,A.K (1991) Molecular cloning of tomato pectinmethylesterase gene and its expression in Rutgers, ripening inhibitor, non-ripening and never-ripe tomato finit. Plant Physiology. 97. 80-87. 

H. Murata, J. L. McEvoy, A. Chatterjee, A. Collmer, A. K. Chatterjee. Molecular cloning of an aepA gene that activates production of extracellular pectolytic, cellulolytic, and proteolytic enzymes in Erwinia carotovora subsp. carotovora. Mol. Plant Micr. Interact. 4 239 (1991). 

K. Higuchi, K. Suzuki, H. Nakanishi, H. Yamaguchi, N. K. Nishizawa, and S. Mori, Cloning of nicotianamine synthase genes, novel genes involved in the biosynthesis of phytosiderophores. Plant Physiol. 779 474 (1999). 

Yang, J. and Z. Guo (2007). Cloning of a 9-cA-epoxycarotenoid dioxygenase gene (SgNCEDl) from Stylosanthes guianensis and its expression in response to abiotic stresses. Plant Cell Rep. 26(8) 1383-1390. 

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