title: The decreased synthesis of chondroitin sulfate-containing extracellular proteoglycans by SV40 transformed Balb/c 3T3 cells.
abstract: Balb/c 3T3 cells synthesize 5--10 times more 35SO2/4- -labeled extracellular proteoglycan per cell than do Balb/c 3T3 cells transformed by SV40 (SV3T3). The extracellular 35SO2/4- -labeled proteoglycans of the Balb/c 3T3 and SV3T3 cells differ markedly in their acid mucopolysaccharide composition. Extracellular Balb/c 3T3 proteoglycans contain about 70--80% chondroitin sulfate, most of which is chondroitin 4-sulfate, and small amounts of heparan sulfate and/or heparin. On the other hand, extracellular SV3T3 proteoglycans contain 65-75% heparan sulfate and/or heparin and less than 15% chondroitin sulfate. Analysis of extracellular 35SO2/4- -labeled proteoglycan by sodium dodecyl sulfate-polyacrylamide gel electrophoresis reveals that Balb/c 3T3 alone synthesizes a class of proteoglycans capable of migrating in a 10% separating gel. This class of proteoglycans, designated as fraction C, accounts for up to 45% of the total extracellular Balb/c 3T3 35 SO2/4- -labeled proteoglycans and contains chondroitin sulfate extracellular SV3T3 proteoglycans. The absence of this and other classes of chondroitin sulfate-containing proteoglycans can account for the 5-10-fold decreased synthesis of 35SO2/4- -labeled proteoglycans by SV3T3 cells when compared to Balb/c 3T3 cells.
mesh_terms: D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002807:Chondroitin / Q000031:analogs & derivatives*; D002809:Chondroitin Sulfates / Q000378:metabolism*; D002810:Chondroitinases and Chondroitin Lyases; D006026:Glycoside Hydrolases; D006821:Hyaluronoglucosaminidase; D011509:Proteoglycans / Q000378:metabolism*; D013539:Simian virus 40 / Q000378:metabolism
chemical_list: D011509:Proteoglycans; D002807:Chondroitin; D002809:Chondroitin Sulfates; D006026:Glycoside Hydrolases; D006821:Hyaluronoglucosaminidase; D002810:Chondroitinases and Chondroitin Lyases