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. 1972 Apr;69(4):951–955. doi: 10.1073/pnas.69.4.951

Regulation of Melanin Synthesis in Mammalian Cells: Effect of Gene Dosage on the Expression of Differentiation*

Richard L Davidson 1,2,3
PMCID: PMC426602  PMID: 4623665

Abstract

Near-tetraploid (2S), pigmented, Syrian hamster cells (34602) were hybridized with unpigmented mouse fibroblasts to produce hybrids that contained two pigment cell genomes and one fibroblast genome per cell (32D). Half of the hybrids were pigmented and showed high activity of the enzyme dihydroxyphenylalanine oxidase; the other half of the hybrids were unpigmented and devoid of the activity of this enzyme. (In contrast, all the previously isolated hybrids containing only one pigment cell genome and one fibroblast genome were unpigmented.) Analyses of the chromosome complement and of a series of enzymes unrelated to melanin synthesis did not reveal any great differences between the pigmented and unpigmented 32D hybrids. Upon the isolation of subclones, unpigmented 32D hybrids produced only unpigmented colonies, whereas pigmented hybrids produced both pigmented and unpigmented colonies. Although the mechanism that results in the formation of some pigmented and some unpigmented hybrids in these experiments is not known, it is clear that the number of pigment cell genomes in a hybrid affects the expression of pigmentation.

Keywords: somatic hybridization, hamster, dihydroxyphenylalanine oxidase, mouse fibroblasts, clones

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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