Unexpected selection to retain high GC content and splicing enhancers within exons of multiexonic lncRNA loci

GC content variation across multiexonic protein-coding (blue) and intergenic lncRNA loci (red) in (A) Drosophila melanogaster (Young et al. 2012), (B) Danio rerio (Ulitsky et al. 2011; Pauli et al. 2012), (C) Latimeria chalumnae (Amemiya et al. 2013), (D) Mus musculus (Belgard et al. 2011), and (E) Homo sapiens (Cabili et al. 2011; Derrien et al. 2012). Nonoverlapping windows each sampling 10% of the sequences were used. The gray band indicates GC content of flanking intergenic sequences. (F) Comparison of exonic GC content between multiexonic and monoexonic intergenic lncRNA loci as well as 5′- and 3′-UTR exons from protein-coding genes in human.