Sequential dimerization of human zipcode-binding protein IMP1 on RNA: a cooperative mechanism providing RNP stability

TY - JOUR

T1 - Sequential dimerization of human zipcode-binding protein IMP1 on RNA: a cooperative mechanism providing RNP stability

AU - Nielsen, J.

AU - Kristensen, M. A.

AU - Willemoes, Martin

AU - Nielsen, F. C.

AU - Christiansen, Jan

PY - 2004

Y1 - 2004

N2 - Active cytoplasmic RNA localization depends on the attachment of RNA-binding proteins that dictate the destination of the RNA molecule. In this study, we used an electrophoretic mobility-shift assay in combination with equilibrium and kinetic analyses to characterize the assembly of the human zipcode-binding protein IMP1 on targets in the 3'-UTR from Igf-II mRNA and in H19 RNA. In both cases, two molecules of IMP1 bound to RNA by a sequential, cooperative mechanism, characterized by an initial fast step, followed by a slow second step. The first step created an obligatory assembly intermediate of low stability, whereas the second step was the discriminatory event that converted a putative RNA target into a ‘locked' stable RNP. The ability to dimerize was also observed between members of the IMP family of zipcode-binding proteins, providing a multitude of further interaction possibilities within RNP granules and with the localization apparatus.

AB - Active cytoplasmic RNA localization depends on the attachment of RNA-binding proteins that dictate the destination of the RNA molecule. In this study, we used an electrophoretic mobility-shift assay in combination with equilibrium and kinetic analyses to characterize the assembly of the human zipcode-binding protein IMP1 on targets in the 3'-UTR from Igf-II mRNA and in H19 RNA. In both cases, two molecules of IMP1 bound to RNA by a sequential, cooperative mechanism, characterized by an initial fast step, followed by a slow second step. The first step created an obligatory assembly intermediate of low stability, whereas the second step was the discriminatory event that converted a putative RNA target into a ‘locked' stable RNP. The ability to dimerize was also observed between members of the IMP family of zipcode-binding proteins, providing a multitude of further interaction possibilities within RNP granules and with the localization apparatus.

U2 - 10.1093/nar/gkh754

DO - 10.1093/nar/gkh754

M3 - Journal article

C2 - 15314207

SN - 0305-1048

VL - 32

SP - 4368

EP - 4376

JO - Nucleic Acids Research

JF - Nucleic Acids Research

IS - 14

ER -