The NHL Domain of BRAT Is an RNA- Binding Domain That Directly Contacts the Hunchback Mrna for Regulation
Downloaded from genesdev.cshlp.org on October 2, 2021 - Published by Cold Spring Harbor Laboratory Press The NHL domain of BRAT is an RNA- binding domain that directly contacts the hunchback mRNA for regulation Inga Loedige,1,8,9 Mathias Stotz,1,8 Saadia Qamar,2,3 Katharina Kramer,2,3 Janosch Hennig,4,5 Thomas Schubert,6 Patrick Lo¨ ffler,7 Gernot La¨ngst,6 Rainer Merkl,7 Henning Urlaub,2,3 and Gunter Meister1,9 1Biochemistry Center Regensburg (BZR), Laboratory for RNA Biology, University of Regensburg, 93053 Regensburg, Germany; 2Bioanalytical Mass Spectrometry, Max Planck Institute for Biophysical Chemistry, 37077 Go¨ ttingen, Germany; 3Bioanalytics, Institute for Clinical Chemistry, University Medical Center Go¨ ttingen, 37075 Go¨ ttingen, Germany; 4Group Biomolecular NMR, Institute of Structural Biology, Helmholtz Zentrum Mu¨ nchen-German Research Center for Environmental Health, 85764 Neuherberg, Germany; 5Center for Integrated Protein Science Munich, Biomolecular NMR, Department Chemie, Technische Universita¨t Mu¨ nchen, 85748 Garching, Germany; 6Institute for Biochemistry III, University of Regensburg, 93053 Regensburg, Germany; 7Institute of Biophysics and Physical Biochemistry, University of Regensburg, 93053 Regensburg, Germany The Drosophila protein brain tumor (Brat) forms a complex with Pumilio (Pum) and Nanos (Nos) to repress hunchback (hb) mRNA translation at the posterior pole during early embryonic development. It is currently thought that complex formation is initiated by Pum, which directly binds the hb mRNA and subsequently recruits Nos and Brat. Here we report that, in addition to Pum, Brat also directly interacts with the hb mRNA. We identify Brat-binding sites distinct from the Pum consensus motif and show that RNA binding and translational repression by Brat do not require Pum, suggesting so far unrecognized Pum-independent Brat functions.
[Show full text]