Twist1-Haploinsufficiency Selectively Enhances the Osteoskeletal Capacity of Mesoderm-derived Parietal Bone through Downregulation of Fgf23

Purpose: This study investigates the postnatal impact of Twist1 haploinsufficiency on the osteoskeletal ability and regeneration on two calvarial bones arising from tissues of different embryonic origin: the neural crest-derived frontal and the mesoderm-derived parietal bones. Results: Twist1 haplonsufficiency selectively enhanced osteogenic and tissue regeneration ability of mesoderm-derived parietal bones. Twist1 haplonsufficiency triggers its selective activity on mesoderm-derived parietal bone through downregulation of the bone-derived hormone Fgf23. Conclusions: Twist1 haploinsufficiency preferentially triggers osteogenic induction of parietal bones which may be beneficial to optimize treatments for skeletal regeneration, reconstruction and repair of mesoderm-derived bone, as well as to alleviate skeletal abnormalities caused by Twist1 haploinsufficiency. Overall design: Total RNA profiles of 21-day old wild type (WT) and Twist1+/- mice were generated by sequencing using Illumina NextSeq.