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.

Epigenetic inheritance of acquired traits through sperm RNAs and sperm RNA modifications

“…This scenario suggests a transfer of tsRNAs between the epididymis and sperm, and is highly intriguing, as a similar transfer might occur in the seminal fluid, where EVs are enriched with mi RNAs and tsRNAs 57 . Moreover, an enrichment of mi RNAs and tsRNAs is also found in serum 58,59 and neuronal synaptic vesicles 60 , both of which exhibit sensitive physiological changes to bodily conditions, such as inflammation, ageing and calorie restriction 58,59,61 . These findings implicate potential connections through EVs at the organismal level and suggest the possibility that EVs can be transported from the soma to the germ line, along with their RNA cargoes.…”

Synaptic vesicles isolated from the electric organ of Torpedo californica and from the central nervous system of Mus musculus contain small ribonucleic acids (sRNAs)

“…We hypothesize that, in addition to neurotransmitters, SVs contain small RNAs (sRNAs; ≤ 40 nucleotides), and in a previous paper provided evidence for the presynaptic origin and luminal presence for the most abundant SV sRNAs [1]. The SV sRNA data presented in this work represent the entirety of the data sets collected for the previous study, including microRNAs associated with the SVs isolated from the electric organ of T. californica not discussed in the previous publication [1]. The data sets produced in these studies have been deposited in the NCBI: SRS1523467, SRS1523466, SRS1523472.…”

Learning-induced mRNA alterations in olfactory bulb mitral cells in neonatal rats

“…Rpp14 mRNA encodes a subunit of the multiprotein RNA complex, Ribonuclease P. Rpp14 with the support of opa-interacting protein 2, acts as an exonuclease removing the 3 ′ end of tRNAs (Jiang and Altman 2002) to generate tRNA fragments. tRNA fragments have been associated with synaptic vesicles and hypothesized to promote local protein synthesis (Li et al 2015). Rpp14 is also a bicistronic mRNA.…”