Hela cells, alkaline phosphatase

The glucocorticoid induction of HeLa cell alkaline phosphatase requires concomitant protein synthesis [100], but immunoprecipitation and radioimmunoprecipitation studies strongly suggest that the quantities of alkaline phosphatase antigen and its rate of synthesis are not altered by the steroid inducer [101]. Physical and biochemical differences have been observed between the uninduced or basal enzyme and the induced form [101]. Thus, the induction does not seem to be due to an increased rate of de novo phosphatase synthesis but more likely is due to the conversion of an antigenic precursor to a catalytically active (or more active) molecule. The conversion process apparently is inhibited... 

Regulation of alkaline phosphatase activity was discussed by Cox and Griffin 65). Steroids such as hydrocortisone or prednisolone (1 (ig/ml of medium) can induce a 3- to 20-fold rise in certain HeLa cell cultures, while other cell lines are induced by 15 mM phenyl phosphate. Recently, it has been shown that fibroblast cell cultures are also stimulated by prednisolone (( ( ). According to one report, Pi may have a control function here a decrease in the level of rat kidney P produced by a low phosphate diet was accompanied by an increase in alkaline phosphatase. Nine other enzymes monitored were unaffected 67). 

Interesting indeed are the recent studies of Griffin and Cox (G20, G21) on the mechanism of adrenocorticoid induction of alkaline phosphatase in human cell cultures. Two temporal phases in the induction of enzyme in HeLa cells are reported a first 12-hour period exhibiting a slow rise in activity, followed by a sudden marked linear increase extending from 15 to 80 hours. The elevation of activity is marked (around 10-fold). The fact that puromycin blocked induction immediately, and actinomycin D... 

Chou JY, Takahashi S (1987) Control of placental alkaline phosphatase gene expression in HeLa cells induction of synthesis by prednisolone and sodium butyrate. Biochemistry 26 3596-3602... 

DeCarli et al., 1963). Also, hormone induction of alkaline phosphatase in HeLa cell cultures has been extensively studied (GriflFen and Cox, 1966 Melnykovych et al., 1967) with attention to chromosomal number (GriflFen and Bottomley, 1969). In the area of development, the diflFer-entiation of alkaline phosphatase has been evaluated (Moog et al., 1969) and in pregnancy, interesting work in the rat (Manning et al., 1969) and in the human (Posen et al., 1969 Fishman et al., 1972) have been conducted. Biochemical work has centered on the role of zinc (Simpson and... 

HeLa cell transfection with various plasmid vectors encoding secreted alkaline phosphatase as the reporter protein is a widely applicable strategy. The plasmid vectors can be tailored to contain different responsive elements. For example, glucocorticoid, cAMP, the binding site of NFkB have been used in SECM single HeLa cell studies. ... 

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