p38α specific-deletion in osteoblast progenitors.

<p>(A) PCR of calvarial bones of control (FF) and knockout (KO) mice using specific primers against <i>Mapk14</i> (<i>p38a</i>) demonstrate gene deletion in KO mice after Cre-mediated recombination. (B) qRT-PCR of mRNA from calvaria or tibia displays <i>p38α</i> (MAPK14) reduced expression in knockout versus control littermates (n = 7 for KO and 13 for FF). (C) Expression of p38 isoforms in primary osteoblasts (p38α/MAPK14; p38β/MAPK11; p38γ/MAPK12; p38δ/MAPK13) (n = 6 independent animals). (D) Calvarial protein levels of p38, phospho-p38, Creb, and phospho-Creb show impaired MAPK signalling in knockout animals (n = 3 independent animals) (*p<0.05; **p<0.01; ***p<0.001).