Differential mRNA transport and the regulation of protein synthesis: selective sensitivity of Purkinje cell dendritic mRNAs to translational inhibition.
Although the majority of mRNAs expressed in neurons are confined to the perikaryon, a growing number appear to be transported into dendrites. It is likely that this allows for the local regulation of protein synthesis within discrete subcellular compartments. Here, three different subcellular distribution patterns are demonstrated for four mRNAs that encode proteins highly expressed in Purkinje cells and their dendrites; mRNAs are found in the perikaryon only, perikaryon and proximal dendrite, or perikaryon and proximal plus distal dendrites. Further, it is shown that transport of an mRNA into the dendrites increases its sensitivity to translational inhibition by diphtheria toxin. These data suggest a simple model whereby the transport machinery can regulate the translation of selected mRNAs. Thus, environmental signals that generally affect translational efficiency in concert with the selectivity provided by the transport machinery could provide a means to locally regulate the synthesis of a restricted pool of proteins.
Bian
F
F
Ohio State Biochemistry Program, Ohio State University, Columbus 43210, USA.
Chu
T
T
Schilling
K
K
Oberdick
J
J
D000818:Animals; D001483:Base Sequence; D001692:Biological Transport; D003433:Crosses, Genetic; D017931:DNA Primers; D003712:Dendrites / Q000378:metabolism*; D004167:Diphtheria Toxin / Q000494:pharmacology*; D005786:Gene Expression Regulation; D017403:In Situ Hybridization; D051379:Mice; D008815:Mice, Inbred Strains; D008822:Mice, Transgenic; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis / Q000187:drug effects; D011689:Purkinje Cells / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D001616:beta-Galactosidase / Q000096:biosynthesis
D017931:DNA Primers; D004167:Diphtheria Toxin; D009419:Nerve Tissue Proteins; D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D001616:beta-Galactosidase