Acquired CCN2 deficiency induces changes in the aortic
gene expression pattern
RNA-sequencing was used to assess aortic transcriptomics changes and to
provide insight into the molecular mechanisms involved in CCN2 actions
in the vasculature and in aneurysm formation. As expected, a heat map
two-way hierarchical clustering of genes and samples showed that CCN2-KO
+ Ang II mice clearly differed from the other sets of mice
(Figure 6A ), but it also exhibited a different aortic gene
expression pattern in the CCN2-KO mice compared to WT group
(Figure 6B ). Although samples were analyzed as pools limiting
the statistical power to detect differentially expressed genes (Rajkumar
et al., 2015), we used them as hypothesis-generating experiments. To
search for potential mechanisms involved in the vascular effects of CCN2
deletion, a GO enrichment analysis was done using the most deregulated
genes obtained from the RNA-Seq studies in the WT vs . CCN2-KO
comparative analysis (67 genes, Q-value < 0.5; fold-change
>0.6) (Table 1 ). In this analysis, BP category
results identified C21-steroid hormone biosynthetic process, cholesterol
metabolic process, steroid biosynthetic and metabolic processes, or
aldosterone biosynthetic process as some of the most deregulated terms
in absence of CCN2. Regarding the CC level, extracellular region,
extracellular space, secretory granule or mitochondrial crista were the
standout terms, while Toll-like receptor 4 binding, scaffold protein
binding, iron ion binding or oxidoreductase activity terms spotlight in
the MF category (Table 2 ).