The measurement of plant polyadenylic acid by hybridisation with radioactive polyuridylic acid.

Saturation hybridisation of polyadenylic acid with [(3)H]polyuridylic acid is described. Under conditions of [(3)H]poly(U) excess, poly(A) is detected in the RNA of a number of higher plants. The ribonuclease resistant hybrids melt sharply when subjected to thermal denaturation. Plant RNA which contains poly(A) sequences detected by [(3)H]poly(U) hybridisation is polydisperse in molecular weight. Data presented shows that the amount of poly(A) in plant RNA is variable. This technique is useful for the qualitative and quantitative detection of poly(A) sequences in higher plant RNA.