title: Human U2B″ protein binding to snRNA stemloops.
abstract: The human U2B″ protein is one of the unique proteins that comprise the U2 snRNP, but it is also a representative of the U1A/U2B″ protein family. In the U2 snRNP, it is bound to Stem-Loop IV (SLIV) of the U2 snRNA. We find that in vitro it binds not only to human SLIV, but also to Stem-Loop II (SLII) from human U1 snRNA and to Drosophila U2 snRNA SLIV. The thermodynamics of these binding interactions show a striking similarity, leading to the conclusion that U2B″ has a relaxed specificity for its RNA targets. The binding properties of U2B″ are distinct from those of human U1A and of Drosophila SNF, despite its high homology to those proteins, and so provide important new information on how this protein family has modulated its target preferences.
authors.affiliation: Department of Biochemistry and Molecular Biophysics, Washington University Medical School, St Louis, MO 63110, United States.
authors.forename: Sandra G
authors.initials: SG
authors.lastname: Williams
authors.forename: Kathleen B
authors.initials: KB
authors.lastname: Hall
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004330:Drosophila; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011485:Protein Binding; D012342:RNA, Small Nuclear / Q000737:chemistry / Q000378:metabolism*; D013816:Thermodynamics; D055517:snRNP Core Proteins / Q000378:metabolism*
chemical_list: D012342:RNA, Small Nuclear; C526408:SNRPB2 protein, human; C405483:U1 small nuclear RNA; C405484:U2 small nuclear RNA; D055517:snRNP Core Proteins