The 5'-linked termini of plant ribosomal ribonucleic acids

The Use of Nucleoside Phosphotransferase and (32P) p-Nitrophenyl Phosphate in the Determination of the 5′-Linked Termini of Ribosomal RNA

“…7 and table 1II. This is in agreement with other studies from this laboratory (6) where spectrophotometry was utilized to estimate the nucleosides after separatiDn by paper chromatography. The presence of the much smaller quantitiies of cytidine and guanosine was not observed in the earlier studies and the fact that they were noted here could be attributable to the increased sensitivity of detection of the present method.…”

“…On the basis of the results obtained and those mentioned previously (6) it is evident that adenosine and uridine are the major terminal 5'-linked nucleosides of cauliflower ribosomal RNA. Thus the correspondence of the results helps to validate the method.…”

“…especially termini released by alkaline hvdrolysis of ribosomal RNA molecules. We have tested the efficacy and the validity of the method by utilizing it in the identification of the 5'-linked termini (free 2',3'-hydroxyl termini) of cauliflower ribosomal RNA in this laboratory by several methods (6). The major disadvantages of the methods currently in use are that (a) they require exceedingly large quantities of RNA which involves manipulations that are bulky and laborious, and (b) the techniques for detecting nucleic acid derivatives are not very sensitive although some progress has been made by the use of labeling techniques.…”

“…Exceptions to the rule are the investigations on wheat germ ribosomal RNA (9, 11) from whence equal amounts of each of the 4 nucleosides were isolated. Recently, evidence was presented from this laboratory which indicated that adenosine and uridine are the predominant 5'-linked termini of wheat germ ribosomal RNA as well as ribosomal RNA from 4 other higher plants and a fungus (6). BECKER AND POLLARD-5'-LINKED TERMINI OF' RIBOSONIAL RNA n-propanol (20 ml).…”