Transcriptome dynamics during the development of heart failure caused by mitochondrial complex I dysfunction and pressure overload

Comprehensive knowledge of the dynamic changes in the cardiac transciptome can inform disease mechanism. Previous transcriptome profiling studies on heart failure rely on either microarray or RNA-Seq with low coverage, leaving a large portion of the transcriptome unexplored. Additionally, previous studies only examined two end stages of the disease, onset and late-stage heart failure. Profile of the transcriptome in the middle stage of disease progression can reveal critical molecular events underlying disease transition. Towards these goals, we conducted a multi-factorial RNA-Seq experiment, comparing the dynamic changes in the transcriptome of two murine models of heart failure, pressure overload and loss of mitochondrial complex I. Our data represents the deepest transcriptome coverage to date, covering onset, progression, and late stage of the disease. We found extensive differences in the expression magnitude and dynamics of the transciptomes in different heart failure models. In addition, such differences are associated with progressive worsening of cardiac physiology. Our analysis revealed that mitochondrial dysfunction combined with stress leads to increased number of differentially expressed long intergenic noncoding RNAs, including a recently identified lincRNA that is a master regulator of the cardiac lineage during development. Cardiac tissues were cleaned with PBS and harvested at 1, 2, 4, and 8 weeks after surgeries by freezing in liquid nitrogen. Cardiac RNA profiles of wild type (WT) and ndufs4H-/- mice after surgeries were generated by deep sequencing at 4 time points, in quadruplicate, using Illumina HiSeq2000. The three factors of the data are genetic (WT vs. ndufs4H-/-), environmental stress (trans-aortic constriction vs. Sham controls), and time (Week 1, Week 2, Week 4 and Week 8). Thus, there are 16 samples in total and each sample has 4 replicates.