Abstract 570: Characteristics of Long Non-coding RNAs in the Brown Norway Rat and Alterations in the Dahl Salt-Sensitive Rat

Abstract

Long non-coding RNAs (lncRNAs) are emerging as important mediators of genomic regulation. lncRNAs, however, remain poorly characterized in the rat model organism, which is widely used in hypertension research. Using poly(A)-independent and strand-specific RNA-seq, we identified approximately 1,500 to 1,800 lncRNAs expressed in each of the following tissues of Brown Norway rats: the renal cortex, renal outer medulla, liver, cardiac left ventricle, adrenal gland, and hypothalamus. Expression patterns and the binding of histone H3K4me3 to promoter regions were confirmed for several of the identified lncRNAs. Patterns of rat lncRNA expression appeared to be more tissue-specific than mRNA. Rat lncRNAs, on average, had similar lengths to mRNA but substantially fewer exons. The median abundance of rat lncRNAs was approximately 40% of that of mRNA. Approximately 28% of the lncRNAs identified in the renal outer medulla appeared to lack a poly(A) tail. Differential expression of 74 lncRNAs was detected in the renal outer medulla between Dahl salt-sensitive SS rats and salt-insensitive, congenic SS.13BN26 rats fed a high-salt diet. Two of the differentially expressed lncRNAs, which were confirmed, were located within the substituted congenic region. The study identified genome-wide characteristics of lncRNAs in the rat model and suggested a role of lncRNAs in hypertension.