title: Dynamics of native β-actin mRNA transport in the cytoplasm.
abstract: Transport of messenger RNAs (mRNAs) in the cytoplasm is essential for localization to translation sites and for post-transcriptional regulation. Utilizing single-RNA sensitive probes and real-time fluorescence microscopy, we accurately quantified the dynamics of native, non-engineered, β-actin mRNAs within the cytoplasm of epithelial cells and fibroblasts for the first time. Using single-particle tracking and temporal analysis, we determined that native β-actin mRNAs, under physiologic conditions, exhibit bursts of intermittent, processive motion on microtubules, interspersed between time periods of diffusive motion, characterized by non-thermal enhanced diffusivity. When transport processes were perturbed via ATP depletion, temperature reduction, dynamitin overexpression and chemical inhibitors, processive motion was diminished or eliminated and diffusivity was reduced. These data support a model whereby processive, motor-driven motion is responsible for long-distance mRNA transport.
authors.affiliation: Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA.
authors.forename: Aaron W
authors.initials: AW
authors.lastname: Lifland
authors.forename: Chiara
authors.initials: C
authors.lastname: Zurla
authors.forename: Joana
authors.initials: J
authors.lastname: Yu
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Santangelo
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism*; D000072159:Dynactin Complex; D004847:Epithelial Cells / Q000378:metabolism / Q000502:physiology; D005347:Fibroblasts / Q000378:metabolism / Q000502:physiology; D006801:Humans; D008856:Microscopy, Fluorescence / Q000379:methods; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional / Q000502:physiology*; D034443:RNA Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D013696:Temperature; D014407:Tumor Cells, Cultured
chemical_list: D000199:Actins; C000606361:DCTN2 protein, human; D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins; D012333:RNA, Messenger; D000255:Adenosine Triphosphate