Metabolism in HeLa cells

Figure 7. Effect of butyrate and cycloheximide on GM3 metabolism in HeLa cells...

Kerwar, S.S., Spears, C., McAuslan, B., and Weissbach, H., 1971. Studies on vitamin B12 metabolism in HeLa cells. Archives of Biochemistry and Biophysics. 142 231-237. 

J PaweUdewicz, M Gorna, W Fenrych, S Magar. Ann NY Acad Sci 112 641, 1964. SS Kerwar, C Spears, B McAuslan, H Weissbach. Studies on vitamin B12 metabolism in Hela cells. Arch Biochem Biophys 142 231-237, 1971. 

Jaluria, P., Betenbaugh, M., Konstantopoulos, K. et al. (2006) Application of microarrays to identify and characterize genes involved in attachment dependence in HeLa cells. Metabolic Engineering, 9, 241-251. 

Treatment with AS-6 caused a decrease in cholesterol levels [150, 151], but it is unclear whether this property relates to its ability to enhance insulin action on lipid metabolism or results from other actions. Although ascochlorin originally was associated with cytotoxic effects in HeLa cell cultures [ 143], chronic studies (10 weeks) in mice with AS-6 showed no effects on food consumption or toxic signs in liver [147]. 

MBOCA induced gene mutations at the thymidine kinase (TK) locus in mouse lymphoma cells (Caspary et al. 1988 Myhr and Caspary 1988). Unscheduled DNA synthesis (UDS) was induced in HeLa cells (Martin and Mcdermid 1981), in rat primary hepatocytes at >10 pmol (McQueen et al. 1981 Mori et al. 1988 Williams et al. 1982), and in hamster (McQueen et al. 1981) and rabbit (McQueen and Wiliams 1987) hepatocytes. The concentration that tested positive in the mouse was 50 jmol (McQueen et al. 1981). Sensitivity to MBOCA showed species-specific variations rat > mouse > hamster > rabbit (McQueen et al. 1981, 1983). Because hepatocytes have their own metabolic activation systems, no exogenous metabolic activation is needed. In assays using attachment independence as an end point, MBOCA, at concentrations near the LC o, transformed baby hamster kidney (Daniel and Dehnel 1981 Styles 1981), rat embryo (Dunkel et al. 1981 Traul et al. 1981), and Balb/3T3 cells (Dunkel et al. 1981). Transformation assays have not been evaluated... 

In an effort to elucidate the degradation processes and the metabolic turnover rate of poly(ADP-ribose) synthetase in living cells, we prepared two types of polyclonal antibodies, one against the calf th3mius native enzyme and another against its catalytic domain. These antibodies efficiently immunoprecipitated both calf and human enzymes in crude extracts. In this paper we present evidence to show that poly(ADP-ribose) synthetase is synthesized in HeLa cells without forming any precursor polypeptide and degraded with a half life of 18 hrs. 

Fig. 5. Rate of degradation of poly(ADP-iibose) synthetase in HeLa cells. HeLa 3S cells (2.5 X 10 in leucine-deprived Dulbecco s modified Eagle s medium (DIFCO Laboratories) containing 5% dialyzed fetal bovine serum were metabolically labeled with 50 pCi pHJleucine (120 Q/mmol) in a 5% COj incubator for 1 hr at 37°C. After the addition of a 5,000 times excess amount of cold leucine (0.5 mM), cells were either harvested immediately or incubated further for chase. The radiolabeled cells were disrupted and immunoprecipitated using al20K (O) or a54K (9) as described in Fig. 3. Quantification of the radiolabeled poly(ADP-iibose) synthetase was carried out by densitometric trace of fluorogram using a chromatoscanner (Shimadzu CD-900).

Salzman, N. P., Lockart, R. Z., and Sebring, E. D., 1959, Alterations in HeLa cell metabolism resulting from poliovirus infection. Virology 9 244. 

Berger EG, Thumher M Muller U. Galactosyltransferase and sialyltransferase are located in different sub-cellular compartments in HeLa cells. Exp Cell Res (EPB) (1987) 173 267-273. Shur BD Roth S. Cell surface glycosyltransferases. Biochem Biophys Ada (1975) 415 473-512. Schachter H Roden L. The biosynthesis of animal glycoproteins. In Metabolic Conjugation and Metabolic Hydrolysis. WH Fishman, Editor Academic Press New York pp. 1-149. McGuire EJ, Kerlin R, Cebra JJ Roth S. A human milk galactosyltransferase is specific for secreted, but not plasma IgA. J Immunol (1989) 143(9) 2933-2938. 

One day prior to the isolation of polysomes, approximately 5 million HeLa cells are plated into 10-cm dishes. The following day, the media is replaced with fresh DMEM and compound is added to a concentration previously determined to inhibit translation in vivo by 35S-methionine metabolic labeling (see previously). 

Although the DNA-binding properties of several procaryotic topoisomerases have been well characterized, little information is currently available concerning eucaryotic enzymes. Some eucaryotic topoisomerases may be intimately associated with other nuclear proteins HeLa topoisomerases I and II have been found to be associated with chromatin (Javaherian and Liu, 1983 Liu et al., 1983b). HeLa topoisomerase I has been shown to bind to the nonhistone protein HMG17, which also stimulates DNA catenation by the enzyme (Javaherian and Liu, 1983 Tse et al., 1984). It has been suggested that type II topoisomerase is an important component of the chromosomal scaffold in interphase nuclei and mitotic chromosomes from chicken cell lines (Earnshaw et al., 1985). In addition, an ATP-dependent topoisomerase has been found associated with several other enzymes of DNA metabolism in a complex (termed the replitase complex) isolated from the nuclei of Chinese hamster embryo fibroblast cells (Noguchi et al., 1983). 

TCII plays a major role in transport of cobalamins to tissues. A receptor for the TCII-B12 complex has been tentatively identified in vitro on HeLa cells,Ehrlich ascites cells,and human fibroblasts. The bound complex is transferred into the cell, where the cobalamin is released and the TCII is degraded in lysosomes (Figure 38-18). An inborn error of vitamin Bj2 metabolism has been attributed to a defect in vitamin B12 release from lysosomes. A congenital... 

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