title: Synaptic vesicles contain small ribonucleic acids (sRNAs) including transfer RNA fragments (trfRNA) and microRNAs (miRNA).
abstract: Synaptic vesicles (SVs) are neuronal presynaptic organelles that load and release neurotransmitter at chemical synapses. In addition to classic neurotransmitters, we have found that synaptic vesicles isolated from the electric organ of Torpedo californica, a model cholinergic synapse, contain small ribonucleic acids (sRNAs), primarily the 5' ends of transfer RNAs (tRNAs) termed tRNA fragments (trfRNAs). To test the evolutionary conservation of SV sRNAs we examined isolated SVs from the mouse central nervous system (CNS). We found abundant levels of sRNAs in mouse SVs, including trfRNAs and micro RNAs (miRNAs) known to be involved in transcriptional and translational regulation. This discovery suggests that, in addition to inducing changes in local dendritic excitability through the release of neurotransmitters, SVs may, through the release of specific trfRNAs and miRNAs, directly regulate local protein synthesis. We believe these findings have broad implications for the study of chemical synaptic transmission.
authors.affiliation: Department of Biology, Texas A&M University, TAMU 3258, College Station, TX 77843-3474 USA.
authors.forename: Huinan
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Biology, Texas A&M University, TAMU 3258, College Station, TX 77843-3474 USA.
authors.forename: Cheng
authors.initials: C
authors.lastname: Wu
authors.affiliation: Department of Biology, Texas A&M University, TAMU 3258, College Station, TX 77843-3474 USA.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Aramayo
authors.affiliation: Department of Biology, Texas A&M University, TAMU 3258, College Station, TX 77843-3474 USA.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Sachs
authors.affiliation: Department of Biology, Texas A&M University, TAMU 3258, College Station, TX 77843-3474 USA.
authors.forename: Mark L
authors.initials: ML
authors.lastname: Harlow
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D005786:Gene Expression Regulation; D051379:Mice; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D018377:Neurotransmitter Agents / Q000378:metabolism; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D012343:RNA, Transfer / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D013569:Synapses / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D009435:Synaptic Transmission / Q000502:physiology; D013572:Synaptic Vesicles / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D016708:Synaptophysin / Q000235:genetics / Q000378:metabolism; D014101:Torpedo / Q000502:physiology; D014158:Transcription, Genetic; D050494:Vesicular Acetylcholine Transport Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D035683:MicroRNAs; D018377:Neurotransmitter Agents; D016708:Synaptophysin; D050494:Vesicular Acetylcholine Transport Proteins; D012343:RNA, Transfer