Biochemical and Biophysical Research Communications, Vol.414, No.3, 506-511, 2011
Disconnected Interacting Protein 1 binds with high affinity to pre-tRNA and ADAT
Disconnected Interacting Protein 1 (DIP1), a member of the double-stranded RNA-binding protein family based on amino acid sequence, was shown previously to form complexes with multiple transcription factors in Drosophila melanogaster. To explore this protein further, we have undertaken sedimentation equilibrium experiments that demonstrate that DIP1-c (longest isoform of DIM) is a dimer in solution, a characteristic common to other members of the dsRNA-binding protein family. The closest sequence identity for DIM is found within the dsRBD sequences of RNA editase enzymes. Consistent with this role, we demonstrate binding of DIP1-c to a potential physiological RNA target: pre-tRNA. In addition, DIP1-c was shown to interact with ADAT, a tRNA deaminase that presumably modifies pre-tRNAs. From these data, we hypothesize that DIP1 may serve an integrator role by binding its dsRNA ligand and recruiting protein partners for the appropriate metabolism of the bound RNA. (C) 2011 Elsevier Inc. All rights reserved.