Figure 1. Differentially expressed genes and pathways in lungs from old compared to young C57/BL6 wild-type mice. (A) Volcano plot of the global gene expression profiling in lungs from old wild type versus young WT mice. Each point represents the difference in expression (log fold-change) between the two groups of mice plotted against the level of statistical significance. Right blue dots represent overexpressed genes, while the left blue dots represent downregulated genes at a significant level of *p< 0.05 and ** p< 0.01. Some Core or associated genes to the Matrisome are plotted in red. (B) The expression of these genes was evaluated by quantitative RT-PCR. Bars represent fold-change of old mice over young ones (dotted line). (C and D) Gene ontology (C) and KEGG (D) functional analysis of dysregulated genes in old WT mice compared to young littermates. The most significant 20 terms are shown in this figure. Threshold criteria considered for the analysis are log Fold change > 1 or <-1 and p-value < 0.05. KEGG: Kyoto Encyclopedia of Genes and Genomes.