title: Construct optimization for studying protein complexes: obtaining diffraction-quality crystals of the pseudosymmetric PSPC1-NONO heterodimer.
abstract: The methodology of protein crystallography provides a number of potential bottlenecks. Here, an approach to successful structure solution of a difficult heterodimeric complex of two human proteins, paraspeckle component 1 (PSPC1) and non-POU domain-containing octamer-binding protein (NONO), that are involved in gene regulation and the structural integrity of nuclear bodies termed paraspeckles is described. With the aid of bioinformatic predictions and systematic screening of a panel of constructs, bottlenecks of protein solubility, crystallization, crystal quality and crystallographic pseudosymmetry were overcome in order to produce crystals that ultimately revealed the structure.
authors.affiliation: School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley, WA 6009, Australia.
authors.forename: Mihwa
authors.initials: M
authors.lastname: Lee
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Passon
authors.forename: Sven
authors.initials: S
authors.lastname: Hennig
authors.forename: Archa H
authors.initials: AH
authors.lastname: Fox
authors.forename: Charles S
authors.initials: CS
authors.lastname: Bond
mesh_terms: D019295:Computational Biology; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation; D006801:Humans; D045586:Intranuclear Inclusion Bodies / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D046912:Multiprotein Complexes / Q000737:chemistry* / Q000378:metabolism; D034521:Nuclear Matrix-Associated Proteins / Q000737:chemistry* / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry* / Q000378:metabolism; D050810:Octamer Transcription Factors / Q000737:chemistry* / Q000378:metabolism; D055503:Protein Multimerization; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D012995:Solubility; D013237:Stereoisomerism
chemical_list: D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; C083214:NONO protein, human; D034521:Nuclear Matrix-Associated Proteins; D009687:Nuclear Proteins; D050810:Octamer Transcription Factors; C450059:PSPC1 protein, human; D016601:RNA-Binding Proteins