Perinuclear localisation of cellular retinoic acid binding protein I mRNA.

Retinoids are important metabolic and developmental regulators that act through nuclear receptors. The cellular retinoic acid binding protein CRABPI has been suggested to play a role in trafficking of retinoic acid but its exact functions and subcellular localisation remain unclear. Here we show that in CHO cells both exogenous CRABPI transcripts and tagged CRABPI protein have a perinuclear distribution that depends upon the 3'UTR of the mRNA. The CRABPI 3'UTR conferred perinuclear localisation on globin reporter transcripts. Deletion analysis indicated that the first 123nt of CRABPI 3'UTR are necessary for localisation of both CRABPI mRNA and protein. We propose that CRABPI mRNA is localised by a signal within its 3'UTR and that this partly determines the distribution of CRABPI protein.