Defining a microRNA-mRNA targetome for calcineurin inhibitor induced nephrotoxicity.
use of calcineurin inhibitors has revolutionized solid organ transplantation increasing
survival rates dramatically. However, calcineurin inhibitor induced nephrotoxicity
severely limits the use of this class of drugs in transplantation and other diseases.
Here we set out to define a microRNA (miRNA)-messenger RNA (mRNA) interaction map to
identify the role of miRNAs in cyclospo... read morerine-induced nephrotoxicity and the gene pathways
they regulate. By integrating miRNA and mRNA expression profiling with photoactivatable
ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) against
endogenous Argonaute 2 (AGO2) protein in human proximal tubule cells, we identified
miRNAs and mRNAs undergoing active targeting in cyclosporine A (CsA) treated cells and
vehicle-treated controls. First, expression profiling of miRNAs and mRNAs in CsA-treated
versus vehicle-treated cells identified the key canonical pathways and cellular
processes which are dysregulated in proximal tubule epithelial cells (PTECs) by CsA. Our
data support a model whereby CsA induces and epithelial-to-mesenchymal-like (EMT-like)
re-programming of PTECs by down-regulation of key apical surface, cell junction, and
adherens junction genes as well as up-regulation of major pro-EMT cell signaling
pathways such as PI3K/AKT, ERK, and TGF-β. Our data indicate that CsA causes
specific changes in miRNAs and mRNAs associated with the RNA-Induced Silencing Complex
(RISC) complex. Pathway enrichment analysis identified canonical pathways specifically
under regulation by miRNAs following CsA treatment. Analysis of active miRNA-mRNA
targeting interactions revealed that CsA suppresses an upstream regulator of JNK and p38
MAPKs by inducing targeting of MAP3K1 by miR-101-3p thereby uncovering a previously
undefined mechanism by which CsA affects calcineurin-independent molecular pathways.
These insights into the molecular pathways governing expression of genes involved in
cyclosporine-induced nephrotoxicity may provide novel therapeutic approaches to
preventing chronic renal injury in transplant
Thesis (Ph.D.)--Tufts University, 2017.
Submitted to the Dept. of Genetics.
Advisor: John Iacomini.
Committee: Rajendra Kumar-Singh, F. Rob Jackson, Karl Munger, and Gavin Schnitzler.
Keyword: Genetics.read less