Affiliation:
1. School of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200031 China
2. School of Biomedical Engineering Hainan University Haikou 570228 China
Abstract
AbstractBone morphogenetic protein (BMP) signaling plays a vital role in differentiation, organogenesis, and various cell processes. As a member of TGF‐β superfamily, the BMP initiation usually accompanies crosstalk with other signaling pathways and simultaneously activates some of them. It is quite challenging to solely initiate an individual pathway. In this study, an opsin‐free optical method to specifically activate BMP receptors (BMPR) and subsequent pSmad1/5/8 cascades by a single‐time scan of a tightly‐focused femtosecond laser in the near infrared range is reported. Via transient two‐photon excitation to intrinsic local flavins near the cell membrane, the photoactivation drives conformational changes of preformed BMPR complexes to enable their bonding and phosphorylation of the GS domain in BMPR‐I by BMPR‐II. The pSmad1/5/8 signaling is initiated by this method, while p38 and pSmad2 are rarely perturbed. Based on a microscopic system, primary adipose‐derived stem cells in an area of 420 × 420 µm2 are photoactivated by a single‐time laser scanning for 1.5 s and exhibit pSmad1/5/8 upregulation and osteoblastic differentiation after 21 days. Hence, an opsin‐free, specific, and noninvasive optical method to initiate BMP signaling, easily accomplished by a two‐photon microscope system is reported.
Funder
National Natural Science Foundation of China
Shanghai Jiao Tong University
Subject
General Physics and Astronomy,General Engineering,Biochemistry, Genetics and Molecular Biology (miscellaneous),General Materials Science,General Chemical Engineering,Medicine (miscellaneous)