FIGURE 1.

Antisense-RNA affinity purification of MBII-52. (A) Preparation of MBII-52 snoRNP from mouse brain. Solubility of MBII-52 upon lysis of nuclei (left) and immunoprecipitation of Fibrillarin from the lysate containing 300 mM NaCl (right). (B) An antisense RNA probe designed for affinity purification. (C, left) MBII-52 and Fibrillarin recovered from large-scale affinity purification. The quantity of MBII-52 was estimated from a standard curve using in vitro transcribed MBII-52 (not shown). Other abundant RNA species, i.e., U3 snoRNA and U6 snRNA, were not included in the eluate. (C, right) Proteins isolated from affinity-purified MBII-52 snoRNP. Different quantity of MBII-52 probe, indicated as + and ++, recovered ∼1 and 1.2 pmol of MBII-52 snoRNA, respectively. See Table 1 to find the corresponding protein of each band. NB, Northern blotting; WB, Western blotting.