Melting of local ordered structures in yeast 5S ribosomsal RNA in aqueous salts

Abstract

Equlibrim and Kinectics of thermal melting of yeast 5s ribosomal RNA in aqueous NaCL with or without mg22+were invisticated by differential thermal melting and temperature jump methods. Two peaks(1 and 2)and a shoulder were between each of melting curves at ionoic strenth i-0.002-0.5 and linerity -free solutions.The local structres were found to be stablized considerably by Mg 2+. the tempreature jump measurements gave the Kinetic melting curve of the structure 1 at i-0.0.3 without Mg2+or with 0.5 mMMg2+.The kinetic Tm coincided well with the corresponding static Tm.For the structure l.various parameters wee calculated form the kinetic data, which indicated a double helical character of the structure i.in the terms of the values of Tm, G-C content, and enthapy change of the transition of the structure models of eukaryotic 5s RNA propesed priveiously was discussed © 1983 IRL Press Limited.