SV40 large-T oncogene inhibits transcription of perlecan-related proteoglycans but stimulates hyaluronan synthesis in a temperature-sensitive renal-tubule principal cell line.
We have analyzed the effects of SV40 large-T oncogene on proteoglycan (PG) synthesis in a temperature-sensitive SV40-transformed renal cell line. Cells shifted from permissive (33 degrees C) to restrictive (39.5 degrees C) temperature, acquired within 48 h the phenotype of principal cells of the renal collecting tubule. They then synthesized hyaluronan, a large-sized PG, small amounts of free GAG chains, and a major approximately 130-kDa heparan sulfate-PG. Sulfated PGs were localized in a basement membrane-like layer and possessed the same core protein (61-70 kDa) derived from perlecan. Expression of large-T oncogene at the permissive temperature induced dramatic alterations of the extracellular matrix, and a 4- and 12-fold reduction in cell-associated and medium-released sulfated PGs, due to a approximately 50% decrease in perlecan mRNA content and gene transcription. This contrasted with a 2-fold increase in actin gene transcription and a 10- and 2-fold rise in the hyaluronan content in cells and medium, respectively. These alterations did not occur in a control cell line (RC.SV3) derived from the same tubule segment but infected with wild-type SV40 strain. They are thus most likely related to the functional state of large-T oncogene and may take part in the early steps of transformation.
Institut National de la Santé et de la Recherche Médicale, Unité 64 Hôpital Tenon, Paris, France.
R
R
Piédagnel
D
D
Prié
R
R
Cassingéna
P M
PM
Ronco
B
B
Lelongt
D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000235:genetics*; D002461:Cell Line, Transformed; D002852:Chromatography, Ion Exchange; D006025:Glycosaminoglycans / Q000378:metabolism; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate / Q000235:genetics* / Q000378:metabolism; D006358:Hot Temperature; D006820:Hyaluronic Acid / Q000096:biosynthesis* / Q000302:isolation & purification; D007150:Immunohistochemistry; D007685:Kidney Tubules, Collecting / Q000166:cytology / Q000378:metabolism*; D009857:Oncogenes; D011509:Proteoglycans / Q000235:genetics* / Q000378:metabolism; D011817:Rabbits; D013464:Sulfuric Acids / Q000378:metabolism; D014158:Transcription, Genetic
D000952:Antigens, Polyomavirus Transforming; D006025:Glycosaminoglycans; D019812:Heparan Sulfate Proteoglycans; D006497:Heparan Sulfate; D006820:Hyaluronic Acid; D011509:Proteoglycans; D013464:Sulfuric Acids; C071927:perlecan