- Hayashi, Yohei;
- Hsiao, Edward C;
- Sami, Salma;
- Lancero, Mariselle;
- Schlieve, Christopher R;
- Nguyen, Trieu;
- Yano, Koyori;
- Nagahashi, Ayako;
- Ikeya, Makoto;
- Matsumoto, Yoshihisa;
- Nishimura, Ken;
- Fukuda, Aya;
- Hisatake, Koji;
- Tomoda, Kiichiro;
- Asaka, Isao;
- Toguchida, Junya;
- Conklin, Bruce R;
- Yamanaka, Shinya
Fibrodysplasia ossificans progressiva (FOP) patients carry a missense mutation in ACVR1 [617G > A (R206H)] that leads to hyperactivation of BMP-SMAD signaling. Contrary to a previous study, here we show that FOP fibroblasts showed an increased efficiency of induced pluripotent stem cell (iPSC) generation. This positive effect was attenuated by inhibitors of BMP-SMAD signaling (Dorsomorphin or LDN1931890) or transducing inhibitory SMADs (SMAD6 or SMAD7). In normal fibroblasts, the efficiency of iPSC generation was enhanced by transducing mutant ACVR1 (617G > A) or SMAD1 or adding BMP4 protein at early times during the reprogramming. In contrast, adding BMP4 at later times decreased iPSC generation. ID genes, transcriptional targets of BMP-SMAD signaling, were critical for iPSC generation. The BMP-SMAD-ID signaling axis suppressed p16/INK4A-mediated cell senescence, a major barrier to reprogramming. These results using patient cells carrying the ACVR1 R206H mutation reveal how cellular signaling and gene expression change during the reprogramming processes.