GSBS Student Publications

Title

Localization of a beta-actin messenger ribonucleoprotein complex with zipcode-binding protein modulates the density of dendritic filopodia and filopodial synapses

GSBS Program

Biochemistry & Molecular Pharmacology

UMMS Affiliation

Graduate School of Biomedical Sciences; Department of Neuroscience

Date

11-14-2003

Document Type

Article

Medical Subject Headings

Actins; Animals; Brain; Brain-Derived Neurotrophic Factor; Cells, Cultured; Coculture Techniques; Dendrites; Green Fluorescent Proteins; Luminescent Proteins; Macromolecular Substances; Neurons; Oligonucleotides, Antisense; Pseudopodia; RNA, Messenger; RNA-Binding Proteins; Rats; Recombinant Fusion Proteins; Ribonucleoproteins; Synapses; Transfection

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

The dendritic transport and local translation of mRNA may be an essential mechanism to regulate synaptic growth and plasticity. We investigated the molecular mechanism and function of beta-actin mRNA localization in dendrites of cultured hippocampal neurons. Previous studies have shown that beta-actin mRNA localization to the leading edge of fibroblasts or the growth cones of developing neurites involved a specific interaction between a zipcode sequence in the 3' untranslated region and the mRNA-binding protein zipcode-binding protein-1 (ZBP1). Here, we show that ZBP1 is required for the localization of beta-actin mRNA to dendrites. Knock-down of ZBP1 using morpholino antisense oligonucleotides reduced dendritic levels of ZBP1 and beta-actin mRNA and impaired growth of dendritic filopodia in response to BDNF treatment. Transfection of an enhanced green fluorescent protein (EGFP)-beta-actin construct, which contained the zipcode, increased the density of dendritic filopodia and filopodial synapses. Transfection of an EGFP construct, also with the zipcode, resulted in recruitment of endogenous ZBP1 and beta-actin mRNA into dendrites and similarly increased the density of dendritic filopodia. However, the beta-actin zipcode did not affect filopodial length or the density of mature spines. These results reveal a novel function for an mRNA localization element and its binding protein in the regulation of dendritic morphology and synaptic growth via dendritic filopodia.

Rights and Permissions

Citation: J Neurosci. 2003 Nov 12;23(32):10433-44.

Related Resources

Link to article in PubMed

Journal Title

The Journal of neuroscience : the official journal of the Society for Neuroscience

PubMed ID

14614102