Alkaline phosphatases genetic control

Biomedical Applications. TRIS AMINO is used for a number of purposes in its pure form, it is an acidimetric standard the USP grade can be utilized intraveneously for therapeutic control of blood acidosis TRIS AMINO also is useful in genetic engineering as a buffering agent for enzyme systems, industrial protein purification, and electrophoresis. AMP has found use as a reagent in enzyme-linked immunoassays. The primary appHcation is for alkaline phosphatase assays. 

Boyer s studies (B39) appear to indicate a lower degree of organ enzyme specificity than that observed by Nisselbaum et al., in that antihuman intestine alkaline phosphatase sera cross-reacted with kidney and placenta. Also, the antihuman bone preparation precipitated alkaline phosphatase from spleen, liver, kidney, and intestine. Boyer considers liver, bone, spleen, and kidney 3-phosphatases to be closely related proteins, followed by intestine and placenta, the enzyme from these latter tissues representing a second and third class of alkaline phosphatase proteins. Intestine and placenta partially cross-react with one another and with a minor kidney component. Three genetic loci are considered by Boyer, therefore, to control the synthesis of alkaline phosphatase. The most recent study in this area is reported by Birkett et al. (B19). 

In developing Drosophila, Schneiderman et al. (S20) observed that development is characterized by the presence of organ-specific bands visible on starch-gel electrophoresis. Moreover, two separate chromosomal loci have been demonstrated one designated Aph (larval) is on chromosome III (B12), and the other locus, Aph-2, is on chromosome II. It is highly significant that the type of alkaline phosphatase in an organ is under genetic control. 

Genetic studies on the domestic fowl (K28, L6) have demonstrated that a fast-moving form of alkaline phosphatase is determined by a simple autosomal dominant gene (Ap ) that is allelic to the slow-moving Ap allele. The organ source of the plasma enzyme was not identified. Among species lower than man, genetic control of alkaline phosphatase has been observed in sheep (Rl, R4) and cattle (Gl). 

B12. Beckman, L., and Johnson, F. M., Variations in larval alkaline phosphatase controlled by Aph Alleles in drosophilia melanogaster. Genetics 49, 829-835 (1964). 

G2. Garen, A., Genetic control of the bacterial enzyme, alkaline phosphatase. In Microbial Genetics (W. Hayes and R. C. Clowes, eds.), pp. 239-247. Cambridge Univ. Press, London and New York, 1960. 

The second hypothesis proposed another possible variant of genetic control (Fig. 33b) based on the suggestion that the production of each of the subfractions of esterase-4 and esterase-6 (4F and 4S, 6F and 6S) is controlled by a separate structural gene. These genes are the product of tandem duplication (Roberts and Baker, 1973). The same explanation holds for the larval and pupal fractions of alkaline phosphatase. 

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