Nuclear-localized tiny RNAs are associated with transcription initiation and splice sites in metazoans.
We have recently shown that transcription initiation RNAs (tiRNAs) are derived from sequences immediately downstream of transcription start sites. Here, using cytoplasmic and nuclear small RNA high-throughput sequencing datasets, we report the identification of a second class of nuclear-specific approximately 17- to 18-nucleotide small RNAs whose 3' ends map precisely to the splice donor site of internal exons in animals. These splice-site RNAs (spliRNAs) are associated with highly expressed genes and show evidence of developmental stage- and region-specific expression. We also show that tiRNAs are localized to the nucleus, are enriched at chromatin marks associated with transcription initiation and possess a 3'-nucleotide bias. Additionally, we find that microRNA-offset RNAs (moRNAs), the miR-15/16 cluster previously linked to oncosuppression and most small nucleolar RNA (snoRNA)-derived small RNAs (sdRNAs) are enriched in the nucleus, whereas most miRNAs and two H/ACA sdRNAs are cytoplasmically enriched. We propose that nuclear-localized tiny RNAs are involved in the epigenetic regulation of gene expression.
Taft
Ryan J
RJ
Institute for Molecular Bioscience, School of Integrative Biology, University of Queensland, St. Lucia, Australia.
Simons
Cas
C
Nahkuri
Satu
S
Oey
Harald
H
Korbie
Darren J
DJ
Mercer
Timothy R
TR
Holst
Jeff
J
Ritchie
William
W
Wong
Justin J-L
JJ
Rasko
John E J
JE
Rokhsar
Daniel S
DS
Degnan
Bernard M
BM
Mattick
John S
JS
D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000235:genetics*; D002843:Chromatin / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000378:metabolism; D006098:Granulocytes / Q000378:metabolism; D006801:Humans; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism; D012313:RNA / Q000235:genetics / Q000378:metabolism*; D022821:RNA Splice Sites / Q000235:genetics*; D034443:RNA Transport / Q000235:genetics*; D020537:RNA, Small Nucleolar / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism; D024363:Transcription Initiation Site; D014158:Transcription, Genetic
D002843:Chromatin; D035683:MicroRNAs; D022821:RNA Splice Sites; D020537:RNA, Small Nucleolar; D012313:RNA