title: Reverse transcriptase-containing particles induced in rous sarcoma virus-transformed rat cells by arginine deprivation.
abstract: Incubation of rat cells transformed by Rous sarcoma virus (RSV) in an arginine-deficient medium resulted in accumulation of particles in the culture medium. Such particles did not appear when the transformed rat cells were incubated in a complete medium nor in the medium of primary rat cells which were incubated either in arginine-deficient or complete media. The particles which were released from the arginine-deprived transformed rat cells resemble C-type particles in their properties. These particles band in sucrose gradients at a density of 1.16 g/ml and contain 35S ribonucleic acid (RNA) molecules and a reverse transcriptase activity. Analysis of the cytoplasm of transformed and primary rat cells, deprived and undeprived of arginine, revealed the presence of reverse transcriptase-containing particles which banded in sucrose gradients at a density of 1.14 g/ml. These particles differed from the particles released into the medium by the arginine-deprived RSV-transformed rat cells. The deoxyribonucleic acid (DNA) molecules synthesized in vitro by the reverse transcriptase present in the particles isolated from the medium of arginine-deprived cells hybridized to RSV RNA, whereas the DNA synthesized by the cell-bound enzyme had no homology to RSV RNA.
mesh_terms: D000818:Animals; D001120:Arginine / Q000378:metabolism*; D001358:Avian Sarcoma Viruses / Q000201:enzymology / Q000302:isolation & purification* / Q000378:metabolism; D002247:Carbon Isotopes; D002471:Cell Transformation, Neoplastic; D002474:Cell-Free System; D002478:Cells, Cultured / Q000378:metabolism / Q000382:microbiology; D002499:Centrifugation, Density Gradient; D002642:Chick Embryo; D003470:Culture Media; D004279:DNA, Viral / Q000096:biosynthesis; D005347:Fibroblasts; D009693:Nucleic Acid Hybridization; D012367:RNA, Viral; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism*; D051381:Rats; D014316:Tritium; D014461:Ultracentrifugation; D014529:Uridine / Q000378:metabolism
chemical_list: D002247:Carbon Isotopes; D003470:Culture Media; D004279:DNA, Viral; D012367:RNA, Viral; D014316:Tritium; D001120:Arginine; D012194:RNA-Directed DNA Polymerase; D014529:Uridine