Browsing by Subject "Mediator complex"

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    Interaction of the Mediator Head module with RNA polymerase II
    (Elsevier, 2012) Cai, Gang; Chaban, Yuriy; Imasaki, Tsuyoshi; Kovacs, Julio A.; Calero, Guillermo; Penczek, Pawel A.; Takagi, Yuichiro; Asturias, Francisco J.; Biochemistry and Molecular Biology, School of Medicine
    Mediator, a large (21 polypeptides, MW ∼1 MDa) complex conserved throughout eukaryotes, plays an essential role in control of gene expression by conveying regulatory signals that influence the activity of the preinitiation complex. However, the precise mode of interaction between Mediator and RNA polymerase II (RNAPII), and the mechanism of regulation by Mediator remain elusive. We used cryo-electron microscopy and reconstituted in vitro transcription assays to characterize a transcriptionally-active complex including the Mediator Head module and components of a minimum preinitiation complex (RNAPII, TFIIF, TFIIB, TBP, and promoter DNA). Our results reveal how the Head interacts with RNAPII, affecting its conformation and function.
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    MED27 Variants Cause Developmental Delay, Dystonia, and Cerebellar Hypoplasia
    (Wiley, 2021) Meng, Linyan; Isohanni, Pirjo; Shao, Yunru; Graham, Brett H.; Hickey, Scott E.; Brooks, Stephanie; Suomalainen, Anu; Joset, Pascal; Steindl, Katharina; Rauch, Anita; Hackenberg, Annette; High, Frances A.; Armstrong-Javors, Amy; Mencacci, Niccolò E.; Gonzàlez-Latapi, Paulina; Kamel, Walaa A.; Al-Hashel, Jasem Y.; Bustos, Bernabé I.; Hernandez, Alejandro V.; Krainc, Dimitri; Lubbe, Steven J.; Van Esch, Hilde; De Luca, Chiara; Ballon, Katleen; Ravelli, Claudia; Burglen, Lydie; Qebibo, Leila; Calame, Daniel G.; Mitani, Tadahiro; Marafi, Dana; Pehlivan, Davut; Saadi, Nebal W.; Sahin, Yavuz; Maroofian, Reza; Efthymiou, Stephanie; Houlden, Henry; Maqbool, Shazia; Rahman, Fatima; Gu, Shen; Posey, Jennifer E.; Lupski, James R.; Hunter, Jill V.; Wangler, Michael F.; Carroll, Christopher J.; Yang, Yaping; Medical and Molecular Genetics, School of Medicine
    The Mediator multiprotein complex functions as a regulator of RNA polymerase II-catalyzed gene transcription. In this study, exome sequencing detected biallelic putative disease-causing variants in MED27, encoding Mediator complex subunit 27, in 16 patients from 11 families with a novel neurodevelopmental syndrome. Patient phenotypes are highly homogeneous, including global developmental delay, intellectual disability, axial hypotonia with distal spasticity, dystonic movements, and cerebellar hypoplasia. Seizures and cataracts were noted in severely affected individuals. Identification of multiple patients with biallelic MED27 variants supports the critical role of MED27 in normal human neural development, particularly for the cerebellum.