Atypical transcription of microRNA gene fragments.
MicroRNAs (miRNAs) are short ( approximately 22 nt) RNAs that impact gene expression by sequence-specific interactions with messenger RNA or promoter sequences of genomic DNA. Ectopic expression of miRNAs can be accomplished by placing fragments of the corresponding miRNA precursor under the control of RNA polymerase II or III (RNAP II/III). Here, we report that, in the absence of exogenous promoters, DNA fragments incorporating miRNA precursors can be delivered directly into a variety of human cells and give rise to the corresponding mature miRNA. Notably, the transcription of these miRNA DNA fragments appears resistant to conventional inhibitors of RNAP I/II/III activity. Taken together, our findings suggest the existence of a previously unrecognized atypical transcription program for miRNA precursor sequences.
Song Gao
Jin
J
Laboratory of Retrovirology, Division of Infectious Diseases, Rhode Island and Miriam Hospitals, Warren Alpert Medical School, Brown University, Providence, RI 02903, USA.
Zhang
Yingjie
Y
Li
Ming
M
Tucker
Lynne D
LD
Machan
Jason T
JT
Quesenberry
Peter
P
Rigoutsos
Isidore
I
Ramratnam
Bharat
B
D002460:Cell Line; D004247:DNA / Q000737:chemistry; D006801:Humans; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000378:metabolism; D012322:RNA Precursors / Q000096:biosynthesis / Q000235:genetics; D014158:Transcription, Genetic
C542359:MIRN143 microRNA, human; D035683:MicroRNAs; D012322:RNA Precursors; D004247:DNA; D012319:RNA Polymerase II