Crystallization and preliminary crystallographic analysis of the second RRM of Pub1 from Saccharomyces cerevisiae

The second RRM of Pub1 from S. cerevisiae was overexpressed, purified and crystallized. Diffraction data were collected to 1.69 Å resolution. mRNA stability is elaborately regulated by elements in the mRNA transcripts and their cognate RNA-binding proteins, which play important roles in regulating gene expression at the post-transcriptional level in eukaryotes. Poly(U)-binding protein 1 (Pub1), which is a major nuclear and cytoplasmic polyadenylated RNA-binding protein in Saccharomyces cerevisiae, is involved in the regulation of mRNA turnover as a trans-acting factor. It binds to transcripts containing the AU-rich element in order to protect them from degradation. Pub1 contains three RNA-recognition motifs (RRMs) which play significant roles in mRNA binding at AU-rich elements and stabilizer elements. In this study, the second RRM of Pub1 was crystallized by the hanging-drop vapour-diffusion method using polyethylene glycol 4000 as a precipitant at 283 K. An X-ray diffraction data set was collected using a single flash-cooled crystal that belonged to space group H3