Description
A few reports have implicated specific lncRNAs in cardiac development or failure, but precise details of lncRNAs expressed in hearts and how their expression may be altered during embryonic heart development or by adult heart disease is unknown. By comparing lncRNA profiles of normal embryonic (~E14), normal adult, and hypertrophied adult hearts we defined a distinct fetal lncRNA abundance signature that includes 157 lncRNAs differentially expressed compared to adults (fold-change = 50%, FDR=0.02), and which was only poorly recapitulated in hypertrophied hearts (17 differentially expressed lncRNAs; 13 of these observed in embryonic hearts). Analysis of protein-coding mRNAs from the same samples identified 22 concordantly and 11 reciprocally regulated mRNAs within 10 kb of dynamically expressed lncRNAs, reciprocal relationships of lncRNA and mRNA levels was validated for the Mccc1 and Relb genes using in vitro lncRNA knockdown in C2C12 cells. Network analysis suggested a central role for lncRNAs in modulating NFkappaB- and CREB1-regulated genes during embryonic heart growth and identified multiple mRNAs within these pathways that are also regulated, but independently of lncRNAs. Overall design: Cardiac polyadenylated RNA (mRNA and lncRNA) profiles were generated from C57BL/6J mouse hearts were generated on Illumina HiSeq 2000 instruments. 7 independent E13.5 hearts, 12 adult hearts (6 at 6 weeks of age, 6 at 16 weeks of age), 4 sham-operated hearts at 12 weeks of age, and 4 hearts after 4 weeks of pressure overload (TAC) at 12 weeks of age.