End-product Repression and Tissue Phenotype


RECENT work from a number of laboratories suggests that the acquisition of tissue-specific enzyme patterns during embryonic development, and maintenance of these patterns in the adult, probably involves control of the expression of polycistronic operons by specific regulator compounds. These compounds can be recognized hormones1, specific macromolecules2,3, or, quite possibly, metabolic end-products of controlled cistrons. The number of regulator compounds required depends on the complexity of the organism and on the number and size of its operons; it is conceivable that an individual operon may carry instructions for more than one biosynthetic sequence. In this report the role of end-products in establishing tissue phenotypes will be examined.

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WALKER, J. End-product Repression and Tissue Phenotype. Nature 206, 1043 (1965). https://doi.org/10.1038/2061043a0

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