TY - JOUR
T1 - Smoothened-dependent and -independent pathways in mammalian noncanonical Hedgehog signaling
AU - Faria, Alessandra V.De S.
AU - Akyala, Adamu Ishaku
AU - Parikh, Kaushal
AU - Brüggemann, Lois W.
AU - Spek, C. Arnold
AU - Cao, Wanlu
AU - Bruno, Marco J.
AU - Bijlsma, Maarten F.
AU - Fuhler, Gwenny M.
AU - Peppelenbosch, Maikel P.
N1 - Funding Information:
The authors declare that they have no conflicts of interest with the contents of this article. This article contains Table S1. 1 Both authors contributed equally to this work. 2Supported by São Paulo Research Foundation (FAPESP) Fellowship 2018/00736-0. 3Supported by a research scholarship provided by the Federal Government of Nigeria (TETFUND) in conjunction with the Nasarawa State University, Keffi (NSUK), Nasarawa State. 4 To whom correspondence should be addressed: Dept. of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, NL-3000 CA Rotterdam, The Netherlands. Tel.: 31-10-7032792; Fax: 31-10-7032793; E-mail: [email protected].
Publisher Copyright:
© 2019 Lin et al. Published under exclusive license by The American Society for Biochemistry and Molecular Biology, Inc.
PY - 2019/6/21
Y1 - 2019/6/21
N2 - Hedgehog proteins are pivotal morphogens acting through a canonical pathway involving first activation of ligand binding to Patched followed by alleviation of Smoothened receptor inhibition, leading to activation of Gli transcription factors. Noncanonical Hedgehog signaling remains poorly characterized but is thought to be mainly dependent on Smoothened. However, Smoothened inhibitors have yielded only partial success in combating Hedgehog signal transduction-dependent cancer, suggesting that noncanonical Smoothened-independent pathways also are clinically relevant. Moreover, several Smoothened-dependent effects (e.g. neurite projection) do not require transcriptional activation, further suggesting biological importance of noncanonical Smoothened-dependent pathways. We comprehensively characterized the cellular kinome in Hedgehogchallenged murine WT and Smoothened-/- fibroblasts as well as Smoothened agonist-stimulated cells. A peptide assay-based kinome analysis (in which cell lysates are used to phosphorylate specific kinase substrates), along with endocytosis, Lucifer Yellow-based, and immunoblotting assays, identified an elaborate signaling network of both Smoothened-dependent and -independent pathways that mediates actin reorganization through Src-like kinases, activates various proinflammatory signaling cascades, and concomitantly stimulates Wnt and Notch signaling while suppressing bone morphogenetic protein (BMP) signaling. The contribution of noncanonical Smoothened-independent signaling to the overall effects of Hedgehog on cellular physiology appears to be much larger than previously envisioned and may explain the transcriptionally independent effects of Hedgehog signaling on cytoskeleton. The observation that Patched-dependent, Smoothened-independent, noncanonical Hedgehog signaling increases Wnt/Notch signaling provides a possible explanation for the failure of Smoothened antagonists in combating Hedgehog-dependent but Smoothened inhibitor-resistant cancer. Our findings suggest that inhibiting Hedgehog-Patched interaction could result in more effective therapies as compared with conventional Smoothened-directed therapies.
AB - Hedgehog proteins are pivotal morphogens acting through a canonical pathway involving first activation of ligand binding to Patched followed by alleviation of Smoothened receptor inhibition, leading to activation of Gli transcription factors. Noncanonical Hedgehog signaling remains poorly characterized but is thought to be mainly dependent on Smoothened. However, Smoothened inhibitors have yielded only partial success in combating Hedgehog signal transduction-dependent cancer, suggesting that noncanonical Smoothened-independent pathways also are clinically relevant. Moreover, several Smoothened-dependent effects (e.g. neurite projection) do not require transcriptional activation, further suggesting biological importance of noncanonical Smoothened-dependent pathways. We comprehensively characterized the cellular kinome in Hedgehogchallenged murine WT and Smoothened-/- fibroblasts as well as Smoothened agonist-stimulated cells. A peptide assay-based kinome analysis (in which cell lysates are used to phosphorylate specific kinase substrates), along with endocytosis, Lucifer Yellow-based, and immunoblotting assays, identified an elaborate signaling network of both Smoothened-dependent and -independent pathways that mediates actin reorganization through Src-like kinases, activates various proinflammatory signaling cascades, and concomitantly stimulates Wnt and Notch signaling while suppressing bone morphogenetic protein (BMP) signaling. The contribution of noncanonical Smoothened-independent signaling to the overall effects of Hedgehog on cellular physiology appears to be much larger than previously envisioned and may explain the transcriptionally independent effects of Hedgehog signaling on cytoskeleton. The observation that Patched-dependent, Smoothened-independent, noncanonical Hedgehog signaling increases Wnt/Notch signaling provides a possible explanation for the failure of Smoothened antagonists in combating Hedgehog-dependent but Smoothened inhibitor-resistant cancer. Our findings suggest that inhibiting Hedgehog-Patched interaction could result in more effective therapies as compared with conventional Smoothened-directed therapies.
UR - https://www.scopus.com/pages/publications/85068252681
U2 - 10.1074/jbc.RA119.007956
DO - 10.1074/jbc.RA119.007956
M3 - Article
C2 - 30992365
AN - SCOPUS:85068252681
SN - 0021-9258
VL - 294
SP - 9787
EP - 9798
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 25
ER -