title: Structural characterization of the Saccharomyces cerevisiae THO complex by small-angle X-ray scattering.
abstract: The THO complex participates during eukaryotic mRNA biogenesis in coupling transcription to formation and nuclear export of translation-competent messenger ribonucleoprotein particles. In Saccharomyces cerevisiae, THO has been defined as a heteropentamer composed of the Tho2p, Hpr1p, Tex1p, Mft1p, and Thp2p subunits and the overall three-dimensional shape of the complex has been established by negative stain electron microscopy. Here, we use small-angle X-ray scattering measured for isolated THO components (Mft1p and Thp2p) as well as THO subcomplexes (Mft1p-Thp2p and Mft1p-Thp2p-Tho2p) to construct structural building blocks that allow positioning of each subunit within the complex. To accomplish this, the individual envelopes determined for Mft1p and Thp2p are first fitted inside those of the Mft1p-Thp2p and Mft1p-Thp2p-Tho2p complexes. Next, the ternary complex structure is placed in the context of the five-component electron microscopy structure. Our model reveals not only the position of each protein in the THO complex relative to each other, but also shows that the pentamer is likely somewhat larger than what was observed by electron microscopy.
authors: Centre for mRNP Biogenesis and Metabolism, Aarhus University, Aarhus, Denmark.
authors: Jesper Buchhave
authors: JB
authors: Poulsen
authors: Centre for mRNP Biogenesis and Metabolism, Aarhus University, Aarhus, Denmark.
authors: Lee Edward
authors: LE
authors: Sanderson
authors: Centre for mRNP Biogenesis and Metabolism, Aarhus University, Aarhus, Denmark.
authors: Emil Dandanell
authors: ED
authors: Agerschou
authors: Centre for mRNP Biogenesis and Metabolism, Aarhus University, Aarhus, Denmark.
authors: Emil
authors: E
authors: Dedic
authors: Pumpkin - Centre for Membrane Pumps in Cells and Disease, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
authors: Thomas
authors: T
authors: Boesen
authors: Centre for mRNP Biogenesis and Metabolism, Aarhus University, Aarhus, Denmark.
authors: Ditlev E
authors: DE
authors: Brodersen
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D012441:Saccharomyces cerevisiae / Q000737:chemistry; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D053838:Scattering, Small Angle; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism; D014961:X-Ray Diffraction; D039221:mRNA Cleavage and Polyadenylation Factors / Q000737:chemistry* / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C512636:HRP1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C405934:THO2 protein, S cerevisiae; C000602623:Tex1 protein, S cerevisiae; C462947:Thp2 protein, S cerevisiae; D014157:Transcription Factors; D039221:mRNA Cleavage and Polyadenylation Factors; C068359:MFT1 protein, S cerevisiae