Conserved transcriptional co-regulation of pyrophosphate homeostasis genes governs systemic mineralization factors in mice and humans

ABSTRACT Inorganic pyrophosphate (PPi) is a critical inhibitor of ectopic calcification, yet transcriptional regulation of genes controlling its systemic production and degradation ( ABCC6 , ALPL , ANKH , ENPP1 ) remains elusive. We hypothesized that PPi homeostasis is governed by evolutionarily conserved transcription factor (TF) network. Promoter-motif analysis of PPi genes revealed conserved enrichment of nuclear receptor TFs (ESR1, NR4A1, RXRA, NR1H3/LXRα) and metabolic regulators (SREBF1, CEBPB, HNF4A) across mouse and human orthologues. Supporting this, analysis of public RNA-seq datasets and RT-qPCR in wild-type and Abcc6 −/− mice demonstrated tight co-expression of these genes in the liver and the kidney, as central transcriptional hub of systemic PPi regulation. Functionally, analyses in mice revealed age-dependent inverse coupling between plasma PPi concentration and serum alkaline phosphatase (AP) activity, with strongest impact during early life. Abcc6 −/− mice exhibited persistently reduced although gradually increasing PPi and altered Pi/PPi ratios during aging. Translating these findings to humans, plasma PPi correlated inversely with AP activity and positively with Pi, though associations were weaker in ABCC6-deficient pseudoxanthoma elasticum patients. These results establish a conserved TF-driven program coordinating hepatic and renal expression of PPi homeostatic genes, highlight early-life sensitivity of PPi balance, and link gene-regulation to circulating mineralization factors, highlighting species-specific and pathology-driven differences.