Figure 2.

Release of RNA and polysomes from the detergent-treated PB fraction. A, The detergent-treated PB fraction was incubated at 4°C for 15 min in the absence (control) or in the presence of 200 mm NaCl, 2% (NH₄)₂SO₄, or 200 mm Tris-HCl, pH 7.5, and then centrifuged at 500g for 10 min. The RNA in the pellet and supernatant was isolated by phenol:chloroform extraction and ethanol precipitated, and then quantified by A₂₆₀. The 1 mm puromycin-treated PBs were incubated in the absence of high salt concentrations. Bars indicate se. B, Release of polysomes from membrane-stripped PBs by NaCl. PBs were treated as above but in the presence of varying concentrations of NaCl, and then the released polysomes were fractionated through a 60% Suc pad, resuspended in buffer U, and quantified by A₂₆₀. The amount of polysome release is estimated from A₂₆₀ readings per gram of seed.