Figure 1.

Both mature polyA^– hTR RNA and polyA⁺ forms of this RNA can accumulate in S.cerevisiae. Total RNAs (Tot) were extracted from yeast strains transformed either with pFL45esno expression vector lacking insert (lane 1) or with the phTR plasmid, derived from pFL45esno, that carries the DNA fragment encoding hTR (lane 2). A sample of the total RNA preparation obtained from the strain containing phTR was incubated with biotinylated oligo(dT) and polyadenylated RNAs bound to oligo(dT) were precipitated using streptavidin-coated magnetic beads. RNAs were recovered from the supernatant (polyA^–, lane 3) or the pellet (polyA⁺, lane 4). All RNAs were separated on a 6% polyacrylamide gel, transferred to a nylon membrane and hybridized with antisense oligonucleotide probes detecting the TLC1, hTR, snR37 or U3 RNA. Positions of molecular weight markers are indicated on the right.