Stability of Soybean Ribosomal RNA in Various Conditions

Abstract

The stability of RNA preparations which were prepared from soybean cotyledons was examined by incubating the RNA solutions of high salt at 20°C in the presence or absence of PVS. Sedimentation profiles of incubated RNA were given by ultracentrifugal analysis and compared with that of original RNA. RNA retained its original size after incubating for 4 hr in the presence of PVS and 200mM KCl, while RNA was completely degraded into small fragments in the absence of PVS after the same treatment.
The purified rRNA which was prepared from 3 day-old hypocotyls was treated with heating, EDTA or urea in the presence of PVS. L-rRNA component was obviously disappeared by heating at 50°C for 5min. Partial disruption of L-rRNA component occurred by dialyzing against urea solution. L-rRNA separated by zonal ultracentrifugation was decomposed into components by heat treatment or leaving at 4°C for 20 hr in the buffer from which KCl was omitted. No back-conversion of heated RNA to original L-rRNA occurred by gradual cooling at room temperature for 40min. S-rRNA, however, seemed to be stable in these treatments compared with L-rRNA.