Neuroblastoma

lnc-SCA7[LncRNA]

miR-124[miRNA]

ATXN7[mRNA]

Embryonic Stem Cells

Mus musculus (mouse)

Nat Struct Mol Biol 2014 Nov 21, 955-961 doi:10.1038/nsmb.2902 PMID:25306109

Cross-talking noncoding RNAs contribute to cell-specific neurodegeneration in SCA7.

Western blot;qRT-PCR;luciferase reporter assays

As observed in N2A cells, lnc-SCA7 knockdown (76% relative to control) in wild-type ES cells significantly reduced the expression of Atxn7 (82% of control). In contrast, in Dcr-deficient ES cells a similar level of lnc-SCA7 knockdown had no significant effect on Atxn7 expression. This is consistent with the regulation of Atxn7 expression by lnc-SCA7 being miRNA-dependent. This conclusion was further supported by the dependence of the reduction in reporter activity after cotransfection of miR-124 mimics and recombinant lnc-SCA7 or Atxn7 luciferase-reporter constructs (23% and 42% of control, respectively) on the presence of the predicted miR-124 MREs in these transcripts. More specifically, transfected constructs bearing inverted seed sequences of all miR-124 MREs predicted within lnc-SCA7 (six MREs) and Atxn7 (two MREs) (hereafter referred to as lnc-SCA7-mut and Atxn7-mut, respec tively) abolished the effect of miR-124 on reporter activity. As expected, neither lnc-SCA7-mut nor Atxn7-mut overexpression (7.7- and 9.7-fold, respectively) had a significant impact on transcript levels of Atxn7 or lnc-SCA7 , consistently with the ability of lnc-SCA7 and Atxn7 transcripts to modulate each other’s abundance in a miR-124 dependent manner.