Sequence complexity of polyadenylate ribonucleic acid in El mouse brain.

To elucidate the sequence complexity of polyadenylate messenger RNA [poly(A+)mRNA] regarding the seizure-susceptible El mouse brain, the proportion of complexity was measured by saturation hybridization using a single-copy DNA (scDNA) with excess RNA. At saturation, 3.81, 3.85 and 4.00% of scDNA hybridized with polysomal poly(A+)mRNAs of El(+), El(O) which had not been convulsed, and ddY (nonsusceptible) mice, respectively. The additive hybridization of a mixture of El(+) and ddY mouse mRNAs was 4.04%. The results suggest that there are considerable overlapping sets within the poly(A+)mRNA sequences between the ddY and El mice, but the complexity of ddY mice mRNA is slightly larger than that of the El mice, whereas poly(A+) heterogeneous nuclear RNA (hnRNA) hybridized with about 18% of scDNA in three strains of mice.