title: The RNAse-RNAse inhibitor system in the liver of the frog Rana esculenta: subcellular distribution and differential binding of inhibitor with multiple RNAses.
abstract: The aim of our work was to investigate the biological basis of the existence of multiple alkaline RNAses in the Rana esculenta liver with respect to formation of a RNAse-RNAse inhibitor complex (latent RNAse). Subcellular distribution indicated that most of the alkaline RNAse activity appeared in the high-speed supernatant and mainly in a latent form bound to an endogenous inhibitor. This RNAse-RNAse inhibitor complex was isolated, the bound RNAse activity was released and found to correspond to RNAse III and RNAse IV, the two most cathodic RNAses present in the supernatant fraction. The two RNAses differed markedly in the ability to interact with the inhibitor and this might be essential for the different biological roles the RNAses may play in the regulation of cytoplasmic RNA level. On the basis of molecular weight determinations we assume that the enzyme-inhibitor complex is shared by two different RNAses.
mesh_terms: D000818:Animals; D001665:Binding Sites; D004791:Enzyme Inhibitors / Q000378:metabolism*; D008862:Microsomes, Liver / Q000201:enzymology*; D008930:Mitochondria, Liver / Q000201:enzymology*; D011893:Rana esculenta; D012260:Ribonucleases / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D012260:Ribonucleases