A serendipitous discovery that in situ proteolysis is essential for the crystallization of yeast CPSF-100 (Ydh1p).
The cleavage and polyadenylation specificity factor (CPSF) complex is required for the cleavage and polyadenylation of the 3'-end of messenger RNA precursors in eukaryotes. During structural studies of the 100 kDa subunit (CPSF-100, Ydh1p) of the yeast CPSF complex, it was serendipitously discovered that a solution that is infected by a fungus (subsequently identified as Penicillium) is crucial for the crystallization of this protein. Further analyses suggest that the protein has undergone partial proteolysis during crystallization, resulting in the deletion of an internal segment of about 200 highly charged and hydrophilic residues, very likely catalyzed by a protease secreted by the fungus. With the removal of this segment, yeast CPSF-100 (Ydh1p) has greatly reduced solubility and can be crystallized in the presence of a minute amount of precipitant.
Mandel
Corey R
CR
Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
Gebauer
Damara
D
Zhang
Hailong
H
Tong
Liang
L
D000595:Amino Acid Sequence; D011232:Chemical Precipitation; D039223:Cleavage And Polyadenylation Specificity Factor / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D003460:Crystallization; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D008969:Molecular Sequence Data; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D012995:Solubility; D039221:mRNA Cleavage and Polyadenylation Factors / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*
C450560:CFT2 protein, S cerevisiae; D039223:Cleavage And Polyadenylation Specificity Factor; D029701:Saccharomyces cerevisiae Proteins; D039221:mRNA Cleavage and Polyadenylation Factors