title: Members of the heterogeneous nuclear ribonucleoprotein H family activate splicing of an HIV-1 splicing substrate by promoting formation of ATP-dependent spliceosomal complexes.
abstract: In this study we analyzed members of the heterogeneous nuclear ribonucleoprotein (hnRNP) H protein family to determine their RNA binding specificities and roles in splicing regulation. Our data indicate that hnRNPs H, H', F, 2H9, and GRSF-1 bind the consensus motif DGGGD (where D is U, G, or A) and aggregate in a multimeric complex. We analyzed the role of these proteins in the splicing of a substrate derived from the HIV-1 tat gene and have shown that hnRNP H family members are required for efficient splicing of this substrate. The hnRNP H protein family members activated splicing of the viral substrate by promoting the formation of ATP-dependent spliceosomal complexes. Mutational analysis of six consensus motifs present within the intron of the substrate indicated that only one of these motifs acts as an intronic splicing enhancer.
authors.affiliation: Department of Biomedical Science, Florida Atlantic University, Boca Raton, Florida 33431, USA.
authors.forename: Michael C
authors.initials: MC
authors.lastname: Schaub
authors.forename: Suzette R
authors.initials: SR
authors.lastname: Lopez
authors.forename: Massimo
authors.initials: M
authors.lastname: Caputi
mesh_terms: D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism*; D020816:Amino Acid Motifs / Q000235:genetics; D002474:Cell-Free System / Q000737:chemistry / Q000378:metabolism; D015696:Gene Products, tat / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015497:HIV-1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D034541:Heterogeneous-Nuclear Ribonucleoprotein Group F-H / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007438:Introns; D046912:Multiprotein Complexes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D039102:Poly(A)-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding / Q000235:genetics; D012326:RNA Splicing; D017381:Spliceosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054322:tat Gene Products, Human Immunodeficiency Virus
chemical_list: C088356:GRSF1 protein, human; D015696:Gene Products, tat; D034541:Heterogeneous-Nuclear Ribonucleoprotein Group F-H; D046912:Multiprotein Complexes; D039102:Poly(A)-Binding Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus; D000255:Adenosine Triphosphate