The expression, regulation and functional significance of multiple Peroxisome proliferator-activated receptor γ transcript variants in bone were studied. PPARG transcripts giving rise to PPARg-1 protein were expressed in human osteoblasts, whereas PPARG-2 transcript and protein remained virtually absent. PPARG expression underwent homologous regulation, was upregulated during differentiation and directly induced by the osteogenic hormone dexamethasone, suggesting a role of PPARg-1 for osteogenesis. Differences between the stabilities of PPARG-1, -3 and -4 were observed. We hypothesize that cell-specific expression patterns of multiple PPARG transcript variants encoding for the same protein but differing in mRNA stabilities enable a fine-tuning of PPARG action, which eventually supports a well-adjusted signal transduction between the cell and its environment.

*Gene Expression Regulation, *RNA Stability, Alternative Splicing, Bone and Bones/cytology/drug effects/*metabolism, Cell Differentiation/drug effects, Cell Line, Dexamethasone/pharmacology, Humans, Osteoblasts/cytology/drug effects/metabolism, PPAR gamma/agonists/*genetics, RNA, Messenger/*metabolism, Thiazolidinediones/pharmacology, Transcription, Genetic/drug effects,
F E B S Letters
Erasmus MC: University Medical Center Rotterdam

Bruedigam, C, Koedam, M, Eijken, H.J.M, & van Leeuwen, J.P.T.M. (2008). Evidence for multiple peroxisome proliferator-activated receptor γ transcripts in bone: fine-tuning by hormonal regulation and mRNA stability. F E B S Letters, 582(11), 1618–1624. doi:10.1016/j.febslet.2008.04.012