title: Direct visualization of mRNA colocalization with mitochondria in living cells using molecular beacons.
abstract: The intracellular localization and specific organelle association of mRNA may reflect essential functions, stages, and stability of mRNA. We report the direct visualization of subcellular localization of K-ras and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNAs in live HDF cells using molecular beacons together with membrane-permeabilization and peptide-based delivery. Unexpectedly, we found that both K-ras and GAPDH mRNAs colocalize with mitochondria. Extensive control studies are performed, including the use of fluorescence in-situ hybridization (FISH), negative-control beacons, and the detection of colocalization of 28S ribosomal RNA with the rough endoplasmic reticulum (ER), suggesting that the mRNA localization and colocalization patterns observed in our study are true and specific. Our observation reveals intriguing subcellular associations of mRNA with organelles such as mitochondria, which may provide new insight into the transport, dynamics, and functions of mRNA and mRNA-protein interactions.
authors.affiliation: Georgia Institute of Technology and Emory University, Department of Biomedical Engineering, Atlanta, Georgia 30332, USA.
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Santangelo
authors.forename: Nitin
authors.initials: N
authors.lastname: Nitin
authors.forename: Gang
authors.initials: G
authors.lastname: Bao
mesh_terms: D002460:Cell Line; D005347:Fibroblasts / Q000378:metabolism*; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D011905:Genes, ras / Q000235:genetics*; D024601:Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+) / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D008856:Microscopy, Fluorescence / Q000379:methods; D008928:Mitochondria / Q000378:metabolism*; D015336:Molecular Probe Techniques; D012333:RNA, Messenger / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D024601:Glyceraldehyde 3-Phosphate Dehydrogenase (NADP+)