title: The yeast THO complex forms a 5-subunit assembly that directly interacts with active chromatin.
abstract: The THO complex is a nuclear structure whose architecture is conserved among all kingdoms and plays an important role in mRNP biogenesis connecting transcription elongation with mRNA maturation and export. Recent data indicates that the THO complex is necessary for the proper expression of some genes, assurance of genetic stability by preventing transcription-associated recombination. Yeast THO has been described as a heterotetramer (Tho2, Hpr1, Mft1 and Thp2) that performs several functions through the interaction with other proteins like Tex1 or the mRNA export factors Sub2 and Yra1, with which it forms the TRanscription and EXport complex (TREX). In this article we review the cellular role of THO, which we show to be composed of five subunits with Tex1 being also an integral part of the complex. We also show a low-resolution structure of THO and localize some of its components. We discuss the consequences of THO interaction with nucleic acids through the unfolded C-terminal region of Tho2, highlighting the importance of unfolded regions in eukaryotic proteins. Finally, we comment on THO recruitment to active chromatin, a role that is linked to mRNA biogenesis.
authors.affiliation: Institute of Biochemistry and Biophysics; Polish Academy of Sciences; Warsaw, Poland; Department of Genetics and Biotechnology; Faculty of Biology; University of Warsaw; Warsaw, Poland.
authors.forename: Kamil
authors.initials: K
authors.lastname: Gewartowski
authors.affiliation: Department of Structure of Macromolecules; Centro Nacional de Biotecnología (CNB-CSIC); Madrid, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Cuéllar
authors.affiliation: Institute of Biochemistry and Biophysics; Polish Academy of Sciences; Warsaw, Poland; Department of Genetics and Biotechnology; Faculty of Biology; University of Warsaw; Warsaw, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Dziembowski
authors.affiliation: Department of Structure of Macromolecules; Centro Nacional de Biotecnología (CNB-CSIC); Madrid, Spain.
authors.forename: José María
authors.initials: JM
authors.lastname: Valpuesta
mesh_terms: D009696:Nucleic Acids / Q000378:metabolism*; D012261:Ribonucleoproteins / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D009696:Nucleic Acids; D012261:Ribonucleoproteins; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors