CLOCK and systemic sclerosis: Gene ontology analysis of upregulated genes in Rag-2−/−Fosl-2tg (vs. Rag-2−/−Fosl-2wt) fibroblasts indicated increased transcription factor pathways (Smad2,3,4, Gata2, Mef2a, Clock), activation of profibrotic and rhythm-related pathways (Wnt interactions, tight-junction interactions, Bmal1-Clock activation circadian expression), and association with an SSc signature (Fig. 6b).