TRIP: a novel double stranded RNA binding protein which interacts with the leucine rich repeat of flightless I.
A northwestern screen of a CHO-K1 cell line cDNA library with radiolabelled HIV-1 TAR RNA identified a novel TAR RNA interacting protein, TRIP. The human trip cDNA was also cloned and its expression is induced by phorbol esters. The N-terminus of TRIP shows high homology to the coiled coil domain of FLAP, a protein which binds the leucine-rich repeat (LRR) of Flightless I (FLI) and the interaction of TRIP with the FLI LRR has been confirmed in vitro . TRIP does not bind single stranded DNA or RNA significantly and binds double stranded DNA weakly. In contrast, TRIP binds double stranded RNA with high affinity and two molecules of TRIP bind the TAR stem. The RNA binding domain has been identified and encompasses a lysine-rich motif. A TRIP-GFP fusion is localised in the cytoplasm and excluded from the nucleus. FLI has a C-terminal gelsolin-like domain which binds actin and therefore the association of TRIP with the FLI LRR may provide a link between the actin cytoskeleton and RNA in mammalian cells.
Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
S A
SA
Wilson
E C
EC
Brown
A J
AJ
Kingsman
S M
SM
Kingsman
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D016466:CHO Cells; D019556:COS Cells; D002461:Cell Line, Transformed; D003001:Cloning, Molecular; D006224:Cricetinae; D003593:Cytoplasm / Q000378:metabolism; D017931:DNA Primers; D018260:Gelsolin; D015870:Gene Expression; D015497:HIV-1 / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D007930:Leucine / Q000378:metabolism*; D008840:Microfilament Proteins; D008934:Mitogens / Q000494:pharmacology; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010703:Phorbol Esters / Q000494:pharmacology; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012330:RNA, Double-Stranded / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear; D015534:Trans-Activators
D017931:DNA Primers; C098179:FLII protein, human; D018260:Gelsolin; C114370:LRRFIP1 protein, human; D008840:Microfilament Proteins; D008934:Mitogens; D010703:Phorbol Esters; D011506:Proteins; D012330:RNA, Double-Stranded; D016601:RNA-Binding Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D015534:Trans-Activators; D007930:Leucine