Biochimica et Biophysica Acta, 717 (1982) 387-397 387 Elsevier Biomedical Press BBA 21188 TURNOVER, CHANGE OF COMPOSITION WITH RATE OF CELL GROWTH AND EFFECT OF PHENYLXYLOSIDE ON SYNTHESIS AND STRUCTURE OF CELL SURFACE SULFATED GLYCOSAMINOGLYCANS OF NORMAL AND TRANSFORMED CELLS CARL P. DIETRICH, HUGO A. ARMELIN *, YEDA L. NOGUEIRA, HELENA B. NADER and YARA M. MICHELACCI Departamento de Bioqulmica, Escola Paulism de Medicina, Cx. Postal 20372, S~o Paulo, SP (Brazil) (Received November 30th, 1981) (Revised manuscript received March 9th, 1982) Key words: Glycosaminoglycan; Cell surface; Phenylxyloside; Sulfation; (Mouse fibroblasO The synthesis of sulfated glycosaminoglycans was analysed in mouse fibroblasts during the transition from exponential growth to quiescent monolayers. 'Normal' Swiss 3"1"3 fibroblasts were compared with SV40 transformed 3T3, C6, ST 1 and HeLa cells, p-Nitrophenyl-O-D-xyloside, an artificial acceptor for glyco- saminoglycans synthesis, was used as a probe. Exponentially growing 'normal' 3T3 cells synthesized both dermatan sulfate and chondroitin 4-sulfate, retaining the latter and releasing the former to the medium. Upon reaching quiescence these cells switched to retention of dermatan sulfate and release of chondroitin 4-sulfate. SV3T3 cells synthesized several fold less sulfated glycosaminoglycans than 'normal' 3T3. Even though SV3T3 cells are able to synthesize dermatan sulfate, they only retained chondroitin 4-sulfate, never switching to retention of dermatan sulfate. These results indicated that the transition from rapidly proliferating to resting GO state in normal cells is accompanied by a switch from chondroitin-sulfate rich to dermatan- sulfate-rich cells. This switching was not observed with transformed cells, which are unable to enter the GO state. Phenylxyloside caused a several fold increase in glycosaminoglycans released to the medium in both cell types, but it did not interfere with either growth rate or cell morphology. Particularly the phenylxyioside treatment led to an increase of more than 10-fold in production of dermatan and chondroitin sulfate by SV3T3, C6, STt and HeLa cells. This demonstrated that transformed cells have a high capacity for glycosaminoglycansynthesis. Analysis of enzymatic degradation products of glycosaminoglycans,synthesized in the presence of phenylxyloside, by normal and transformed cells, led to the finding of 4- and 6-sulfated iduronic and glucuronic acid-containing disaccharides. This result indicated that the xyloside causes the synthesis of a peculiar chondroitin sulfate/dermatan sulfate, in both normal and transformed cells. * Present address: Instituto de Quimica, Universidade de Sio Paulo, Cx. Postal 20780, S~lo Paulo, SP, Brazil. Abbreviations: ADi-4S, 2-acetamido-2-deoxy-3-O-(fl-o-gluco- 4-enepyranosyluronic acid)-4-O-sulfo-D-galactose; ADi-6S, 2- acetamido-2-deoxy-3-O-(fl-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose; ADi-NS, 2-sulfamino-2-dooxy-4- O-(glyco-4-enepyranosyluronic acid)-D-glucose; ADi-DiS, 2- sulfamino-2-deoxy-4-O-( fl-D-glyco-4-enepyranosyluronic acid)- D-glucose 6-sulfate. 0304-4165/82/0000-0000/$02.75 © 1982 Elsevier Biomedical Press Introduction A great deal of attention has been given re- cently to the chemical characterization of mam- malian cell surface components and tissue matrices. However, most of the studies have been focused on proteins be it collagens or large glycoproteins such as fibronectin and laminin [1,2]. It is now evident that heparan sulfate, dermatan sulfate and