Evidence for the presence of a cell-surface ribonuclease in mechanically prepared rat-liver cells in suspension.
Rat-liver parenchymal cells obtained in suspension by a mechanical method are shown to contain a cell-surface nuclease(s) that rapidly degrades exogenously added total Escherichia coli RNA. However, no acid-soluble products are formed; all the degradation products in the incubation medium sediment in the 4-5S RNA region on a sucrose density gradient. A part of the degraded RNA seems to be taken up by the cells; the uptake of the degradation products, presumably derived from rRNAs, is more than that of purified 4-5S RNA. Most of the RNA taken up by the cell sediments in the 4-5S region; only a small proportion is degraded to acid-soluble material within the cell.
D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D002499:Centrifugation, Density Gradient; D005260:Female; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008297:Male; D008970:Molecular Weight; D051381:Rats; D011919:Rats, Inbred Strains; D012260:Ribonucleases / Q000302:isolation & purification / Q000378:metabolism*
D012260:Ribonucleases