Differential subcellular mRNA targeting: deletion of a single nucleotide prevents the transport to axons but not to dendrites of rat hypothalamic magnocellular neurons.

AUTOR(ES)

Mohr, E

RESUMO

It has previously been shown that mRNA encoding the arginine vasopressin (AVP) precursor is targeted to axons of rat magnocellular neurons of the hypothalamo-neurohypophyseal tract. In the homozygous Brattle-boro rat, which has a G nucleotide deletion in the coding region of the AVP gene, no such targeting is observed although the gene is transcribed. RNase protection and heteroduplex analyses demonstrate that, in heterozygous animals, which express both alleles of the AVP gene, the wild-type but not the mutant transcript is subject to axonal compartmentation. In contrast, wild-type and mutant AVP mRNAs are present in dendrites. These data suggest the existence of different mechanisms for mRNA targeting to the two subcellular compartments. Axonal mRNA localization appears to take place after protein synthesis; the mutant transcript is not available for axonal targeting because it lacks a stop codon preventing its release from ribosomes. Dendritic compartmentation, on the other hand, is likely to precede translation and, thus, would be unable to discriminate between the two mRNAs.

Documentos Relacionados

• Inhibition of protein synthesis alters the subcellular distribution of mRNA in neurons but does not prevent dendritic transport of RNA.
• Distribution of mRNA for the GABA transporter GAT-1 in the rat brain: evidence that GABA uptake is not limited to presynaptic neurons.
• Expression of preproenkephalin mRNA by cultured astrocytes and neurons.
• Depolarizing influences regulate preprotachykinin mRNA in sympathetic neurons.
• An exon that prevents transport of a mature mRNA