Somatic fusion

The cultivated potato and many of its relatives are amenable to eell and tissue culture procedures, ineluding protoplast isolation and fusion. Somatic cell fusions have frequently been used to eombine the genomes of Solarium speeies that are sexually ineompatible because of pollen-stylar interactions or mismatched EBN numbers. Somatic fusion circumvents sexual reproduetion and results in novel eombinations of not only nuclear genomes, but also cytoplasmic genomes (Trabelsi et al., 2005 Bidani et al., 2007 Lovene et al., 2007). However, recalcitrant genotypes... 

Sometimes levels of resistance are not as high in somatic fusion hybrids as in the donor clones, presumably due to a dilution effect in the polyploid hybrids (Cooper-Bland, 1994 Rasmussen et al., 1998 Carputo et al, 2000b McGrath, 2002 Gavrilenko, 2003). On the other hand, somatic hybrids produced from fusions of cultivated potato with the wild species S. nigrum were often more resistant than the resistant wild parent, perhaps due to complementation of resistance genes (Zimnoch-Guzowska, 2003). 

Austin, S., Helgeson, J. R, von Wettstein, D., Chua, N. -H. (1987). Interspecific somatic fusions between Solanum brevidens and S. tuberosum. Plenum Publishing Corp, New York, pp. 209-222. 

Helgeson, J. R, Haberlach, G. T., Rohlman, J., Austin, S. (1988). Somatic fusions of Solanum species. Plant Cell Tissue and Organ Culture, 12, 185-187. 

Thach, N. Q. F., U., Wenzel, G. (1993). Somatic fusion for combining virus resistances in Solanum tuberosum L. Theoretical and Applied Genetics 85, 863-867. 

The use of protoplasts in studies of stress physiology and biochemistry expands the advantages of cell culture systems discussed in the preceding sections. Additional applications are related to the fusion of protoplasts. Intraspecifie and interspecific protoplast fusion greatly enhance genetic variability of the fused protoplasts (Kumar Cocking, 1987). The resulting somatic hybrids provide cells which can be used for selection of specific traits (e.g. environmental stress tolerance) provided by one or both donor cells and for basic studies on cytoplasmic and nuclear inheritance of desired characteristics. 

Spontaneous fusion of cultured cells occurs only rarely. However, the rate at which it happens can be markedly increased by the addition of certain viruses or chemical fusogens to the culture. Sendai virus, as used in early somatic cell fusions, has a lipoprotein envelope similar in structure to the animal cell membrane. It has been suggested that a glycoprotein in the envelope promotes cell fusion by an as yet unexplained mechanism. 

Brinster, R.L., Chen, H.Y., Trumbauer, M., Senear, A.W., Warren, R., and Palmiter, R.D. (1981) Somatic expression of herpes thymidine kinase in mice following injection of a fusion gene into eggs. Cell 27, 223-231. 

Monoclonal antibodies (MAbs) produced through the technique of somatic cell fusion are fundamental tools in the exploration of chemokine biology. This chapter details the procedures that were used to generate a panel of MAbs directed against the human chemokine RANTES (1,2). The general approach described here should be broadly applicable to the generation of MAbs directed against other members of this cytokine family. 

As late as 1984, scientists David McGrath and Davor Solter wrote in the journal Science, The cloning of mammals by simple nuclear transfer is biologically impossible. That assertion has been proven false, and since that date sheep, mice, cows, monkeys—a virtual menagerie of mammals—have been cloned. A moratorium on the cloning of humans has been enforced by law and by intimidation. Yet the announcement of the first true human clone— from somatic cell and egg cell fusion to embryonic birth—is only a question of time. Whether it occurs in a federal laboratory or in a private clinic, it will happen. 

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