Optogenetic Control of the BMP Signaling Pathway

Abstract

Bone morphogenetic proteins (BMPs) are members of the transforming growth factor β (TGFβ) superfamily and have crucial roles during development; including mesodermal patterning and specification of renal, hepatic, and skeletal tissues. In vitro developmental models currently rely upon costly and unreliable recombinant BMP proteins that do not enable dynamic or precise activation of the BMP signaling pathway. Here, we report the development of an optogenetic BMP signaling system (optoBMP) that enables rapid induction of the canonical BMP signaling pathway driven by illumination with blue light. We demonstrate the utility of the optoBMP system in multiple human cell lines to initiate signal transduction through phosphorylation and nuclear translocation of SMAD1/5, leading to upregulation of BMP target genes including Inhibitors of DNA binding ID2 and ID4 . Furthermore, we demonstrate how the optoBMP system can be used to fine-tune activation of the BMP signaling pathway through variable light stimulation. Optogenetic control of BMP signaling will enable dynamic and high-throughput intervention across a variety of applications in cellular and developmental systems.

Optogenetic‐mediated cardiovascular differentiation and patterning of human pluripotent stem cells

“…More recently, Wnt and BMP signaling pathways were identified as critical cues for cardiac organoid selforganization and chamber formation in 3D, in which CMs and endothelial cells were both formed in the same aggregates. 19,20 With the advent of optogenetic control of BMP signaling, 23 we may be able to precisely pattern the differentiation of CMs, endothelial cells and/or epicardial cells via optogenetics to achieve spatially-organized cardiac tissues/ organoids with high consistency and reproducibility. In the future, OptoWnt could be combined with 3D cell culture, orthogonal light control of other developmental signaling pathways, and advanced optical patterning techniques to achieve more physiologically relevant hPSC organoid models with intricate geometries and orthogonally controlled cell positions for studying human development and disease.…”

Revisiting the Role of TGFβ Receptor Internalization for Smad Signaling: It is Not Required in Optogenetic TGFβ Signaling Systems

“…It is worth noting that other groups have recently shown that Smad1/5 activation can be induced in optogenetic BMP and TGFBR/ACVR signaling systems when BMPR1B/BMPR2 or TGFBR1/ ACVR1 proteins are anchored to the plasma membrane through an N-terminal myristoylation. [22,23] If TGFβ receptor internalization is not necessary for Smad2 activation, to what extent might it contribute to Smad2 signaling? It has been reported that chemical inhibition of endocytosis can impair TGFβ-induced Smad2 nuclear translocation.…”

Optogenetic Application to Investigating Cell Behavior and Neurological Disease

“…Our optoWnt system involves fusion of the intracellular portion of the canonical Wnt co-receptor LRP6 to the PHR domain of Cry2 ( Figure 1D ), and we have reported optogenetic activation of Wnt signaling in both adult neural stem cells (NSCs; Bugaj et al, 2013 ) and human embryonic stem cells (hESCs; Repina et al, 2020 ). Other emerging and relevant morphogen signals to neurodevelopment include optoFGFR1(Kim et al, 2014 ), optoTGF (Li et al, 2018 ), optoBMP (Humphreys et al, 2020 ), and optoBrn2 (Sokolik et al, 2015 ), which have clear applications in modeling neurodevelopment and neurogenesis if translated to either pluripotent stem cells or adult neural stem cells.…”