Differential expression patterns of miRNA clusters in murine ocular tissues. Heat-map diagram of the two-way hierarchical clustering of 285 miRNAs (Delta Log2 median ratio ΔLMR ≥ 0.5) showing relative miRNA expression levels in different tissues of the adult murine eye. Colors indicate relative expression compared to the mean for each miRNA in the entire eye. Distinct clusters of tissue-enriched miRNAs are revealed. At a five-node-level, five miRNA clusters are obtained enriched in one or more tissues: retina (A), RPE (B), retina and/or lens (C), lens and/or cornea (D) and cornea and/or RPE (E). The 25 miRNA sub-clusters selected for GO term enrichment analysis are highlighted with blue lines. From the following groups of miRNAs with identical sequence, only the first member is annotated in the heat-map: mmu-let-7a*/mmu-let-7c-2*; mmu-miR-466a-3p/mmu-miR-466b-3p/mmu-miR-466c-3p/mmu-miR-466e-3p; mmu-miR-467a*/mmu-miR-467d*; mmu-miR-297a*/mmu-miR-297c*/mmu-miR-297b-3p and mmu-miR-199a-3p/mmu-miR-199b. sc: sub-cluster.