scholarly journals Cercosporamide inhibits bone morphogenetic protein receptor type I kinase activity in zebrafish

2020 ◽  
Author(s):  
Jelmer Hoeksma ◽  
Gerard C.M. van der Zon ◽  
Peter ten Dijke ◽  
Jeroen den Hertog

AbstractZebrafish models are well established tools for investigating underlying mechanisms of diseases. Here, we identified cercosporamide, a metabolite from the fungus Ascochyta aquiliqiae, as a potent bone morphogenetic protein (BMP) type I receptor kinase inhibitor through a zebrafish embryo phenotypic screen. The developmental defects in zebrafish, including lack of the ventral fin induced by cercosporamide was strikingly similar as the phenotypes caused by renowned small molecule BMP type I receptor kinase inhibitors and inactivating mutations in zebrafish BMP receptors. In mammalian cell-based assays, cercosporamide blocked BMP/SMAD-dependent transcriptional reporter activity and BMP-induced SMAD1/5-phosphorylation. Biochemical assays with a panel of purified recombinant kinases demonstrated that cercosporamide directly inhibited kinase activity of BMP type I receptors (also called activin receptor-like kinases (ALKs)). In mammalian cells, cercosporamide selectively inhibited constitutively active BMP type I receptor-induced SMAD1/5 phosphorylation. Importantly, cercosporamide rescued the developmental defects caused by constitutively active Alk2 in zebrafish embryos. Taken together, we believe cercosporamide may be the first of a new class of molecules with potential to be developed further for clinical use against diseases that are causally linked to overactivation of BMP receptor signaling, including Fibrodysplasia ossificans progressiva and diffuse intrinsic pontine glioma.

2020 ◽  
Vol 13 (9) ◽  
pp. dmm045971 ◽  
Author(s):  
Jelmer Hoeksma ◽  
Gerard C. M. van der Zon ◽  
Peter ten Dijke ◽  
Jeroen den Hertog

ABSTRACTZebrafish models are well-established tools for investigating the underlying mechanisms of diseases. Here, we identified cercosporamide, a metabolite from the fungus Ascochyta aquiliqiae, as a potent bone morphogenetic protein receptor (BMPR) type I kinase inhibitor through a zebrafish embryo phenotypic screen. The developmental defects in zebrafish, including lack of the ventral fin, induced by cercosporamide were strikingly similar to the phenotypes caused by renowned small-molecule BMPR type I kinase inhibitors and inactivating mutations in zebrafish BMPRs. In mammalian cell-based assays, cercosporamide blocked BMP/SMAD-dependent transcriptional reporter activity and BMP-induced SMAD1/5-phosphorylation. Biochemical assays with a panel of purified recombinant kinases demonstrated that cercosporamide directly inhibited kinase activity of type I BMPRs [also called activin receptor-like kinases (ALKs)]. In mammalian cells, cercosporamide selectively inhibited constitutively active BMPR type I-induced SMAD1/5 phosphorylation. Importantly, cercosporamide rescued the developmental defects caused by constitutively active Alk2 in zebrafish embryos. We believe that cercosporamide could be the first of a new class of molecules with potential to be developed further for clinical use against diseases that are causally linked to overactivation of BMPR signaling, including fibrodysplasia ossificans progressiva and diffuse intrinsic pontine glioma.This article has an associated First Person interview with the first author of the paper.


2020 ◽  
Vol 21 (18) ◽  
pp. 6498
Author(s):  
Chen Xie ◽  
Wenjuan Jiang ◽  
Jerome J. Lacroix ◽  
Yun Luo ◽  
Jijun Hao

Activins transduce the TGF-β pathway through a heteromeric signaling complex consisting of type I and type II receptors, and activins also inhibit bone morphogenetic protein (BMP) signaling mediated by type I receptor ALK2. Recent studies indicated that activin A cross-activates the BMP pathway through ALK2R206H, a mutation associated with Fibrodysplasia Ossificans Progressiva (FOP). How activin A inhibits ALK2WT-mediated BMP signaling but activates ALK2R206H-mediated BMP signaling is not well understood, and here we offer some insights into its molecular mechanism. We first demonstrated that among four BMP type I receptors, ALK2 is the only subtype able to mediate the activin A-induced BMP signaling upon the dissociation of FKBP12. We further showed that BMP4 does not cross-signal TGF-β pathway upon FKBP12 inhibition. In addition, although the roles of type II receptors in the ligand-independent BMP signaling activated by FOP-associated mutant ALK2 have been reported, their roles in activin A-induced BMP signaling remains unclear. We demonstrated in this study that the known type II BMP receptors contribute to activin A-induced BMP signaling through their kinase activity. Together, the current study provided important mechanistic insights at the molecular level into further understanding physiological and pathophysiological BMP signaling.


1999 ◽  
Vol 112 (20) ◽  
pp. 3519-3527 ◽  
Author(s):  
T. Ebisawa ◽  
K. Tada ◽  
I. Kitajima ◽  
K. Tojo ◽  
T.K. Sampath ◽  
...  

Bone morphogenetic protein (BMP)-6 is a member of the transforming growth factor (TGF)-(β) superfamily, and is most similar to BMP-5, osteogenic protein (OP)-1/BMP-7, and OP-2/BMP-8. In the present study, we characterized the endogenous BMP-6 signaling pathway during osteoblast differentiation. BMP-6 strongly induced alkaline phosphatase (ALP) activity in cells of osteoblast lineage, including C2C12 cells, MC3T3-E1 cells, and ROB-C26 cells. The profile of binding of BMP-6 to type I and type II receptors was similar to that of OP-1/BMP-7 in C2C12 cells and MC3T3-E1 cells; BMP-6 strongly bound to activin receptor-like kinase (ALK)-2 (also termed ActR-I), together with type II receptors, i.e. BMP type II receptor (BMPR-II) and activin type II receptor (ActR-II). In addition, BMP-6 weakly bound to BMPR-IA (ALK-3), to which BMP-2 also bound. In contrast, binding of BMP-6 to BMPR-IB (ALK-6), and less efficiently to ALK-2 and BMPR-IA, together with BMPR-II was detected in ROB-C26 cells. Intracellular signalling was further studied using C2C12 and MC3T3-E1 cells. Among the receptor-regulated Smads activated by BMP receptors, BMP-6 strongly induced phosphorylation and nuclear accumulation of Smad5, and less efficiently those of Smad1. However, Smad8 was constitutively phosphorylated, and no further phosphorylation or nuclear accumulation of Smad8 by BMP-6 was observed. These findings indicate that in the process of differentiation to osteoblasts, BMP-6 binds to ALK-2 as well as other type I receptors, and transduces signals mainly through Smad5 and possibly through Smad1.


2008 ◽  
Vol 30 (3) ◽  
pp. 379-390 ◽  
Author(s):  
Frederick S. Kaplan ◽  
Meiqi Xu ◽  
Petra Seemann ◽  
J. Michael Connor ◽  
David L. Glaser ◽  
...  

2021 ◽  
Vol 22 (9) ◽  
pp. 4553
Author(s):  
Satoshi Fujisawa ◽  
Motoshi Komatsubara ◽  
Naoko Tsukamoto-Yamauchi ◽  
Nahoko Iwata ◽  
Takahiro Nada ◽  
...  

Orexin is expressed mainly in the hypothalamus and is known to activate the hypothalamic–pituitary–adrenal (HPA) axis that is involved in various stress responses and its resilience. However, the effects of orexin on the endocrine function of pituitary corticotrope cells remain unclear. In this study, we investigated the roles of orexin A in pro-opiomelanocortin (POMC) transcription using mouse corticotrope AtT20 cells, focusing on the bone morphogenetic protein (BMP) system expressed in the pituitary. Regarding the receptors for orexin, type 2 (OXR2) rather than type 1 (OX1R) receptor mRNA was predominantly expressed in AtT20 cells. It was found that orexin A treatment enhanced POMC expression, induced by corticotropin-releasing hormone (CRH) stimulation through upregulation of CRH receptor type-1 (CRHR1). Orexin A had no direct effect on the POMC transcription suppressed by BMP-4 treatment, whereas it suppressed Smad1/5/9 phosphorylation and Id-1 mRNA expression induced by BMP-4. It was further revealed that orexin A had no significant effect on the expression levels of type I and II BMP receptors but upregulated inhibitory Smad6/7 mRNA and protein levels in AtT20 cells. The results demonstrated that orexin A upregulated CRHR signaling and downregulated BMP-Smad signaling, leading to an enhancement of POMC transcription by corticotrope cells.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Christopher Agnew ◽  
Pelin Ayaz ◽  
Risa Kashima ◽  
Hanna S. Loving ◽  
Prajakta Ghatpande ◽  
...  

AbstractUpon ligand binding, bone morphogenetic protein (BMP) receptors form active tetrameric complexes, comprised of two type I and two type II receptors, which then transmit signals to SMAD proteins. The link between receptor tetramerization and the mechanism of kinase activation, however, has not been elucidated. Here, using hydrogen deuterium exchange mass spectrometry (HDX-MS), small angle X-ray scattering (SAXS) and molecular dynamics (MD) simulations, combined with analysis of SMAD signaling, we show that the kinase domain of the type I receptor ALK2 and type II receptor BMPR2 form a heterodimeric complex via their C-terminal lobes. Formation of this dimer is essential for ligand-induced receptor signaling and is targeted by mutations in BMPR2 in patients with pulmonary arterial hypertension (PAH). We further show that the type I/type II kinase domain heterodimer serves as the scaffold for assembly of the active tetrameric receptor complexes to enable phosphorylation of the GS domain and activation of SMADs.


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