Neuropilin-1 promotes Hedgehog signaling through a novel cytoplasmic motif

J Biol Chem. 2017 Sep 15;292(37):15192-15204. doi: 10.1074/jbc.M117.783845. Epub 2017 Jun 30.


Hedgehog (HH) signaling critically regulates embryonic and postnatal development as well as adult tissue homeostasis, and its perturbation can lead to developmental disorders, birth defects, and cancers. Neuropilins (NRPs), which have well-defined roles in Semaphorin and VEGF signaling, positively regulate HH pathway function, although their mechanism of action in HH signaling remains unclear. Here, using luciferase-based reporter assays, we provide evidence that NRP1 regulates HH signaling specifically at the level of GLI transcriptional activator function. Moreover, we show that NRP1 localization to the primary cilium, a key platform for HH signal transduction, does not correlate with HH signal promotion. Rather, a structure-function analysis suggests that the NRP1 cytoplasmic and transmembrane domains are necessary and sufficient to regulate HH pathway activity. Furthermore, we identify a previously uncharacterized, 12-amino acid region within the NRP1 cytoplasmic domain that mediates HH signal promotion. Overall, our results provide mechanistic insight into NRP1 function within and potentially beyond the HH signaling pathway. These insights have implications for the development of novel modulators of HH-driven developmental disorders and diseases.

Keywords: Hedgehog signaling pathway; Neuropilin; PKA; cell signaling; cell surface receptor; cilia; signal transduction.

Publication types

  • Comparative Study

MeSH terms

  • Amino Acid Motifs
  • Animals
  • COS Cells
  • Cells, Cultured
  • Chlorocebus aethiops
  • Embryo, Mammalian / cytology
  • Genes, Reporter
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • Hedgehog Proteins / metabolism*
  • Humans
  • Kruppel-Like Transcription Factors / agonists*
  • Kruppel-Like Transcription Factors / chemistry
  • Kruppel-Like Transcription Factors / genetics
  • Kruppel-Like Transcription Factors / metabolism
  • Mice
  • Mice, Mutant Strains
  • Models, Biological*
  • Mutation
  • NIH 3T3 Cells
  • Neuropilin-1 / chemistry
  • Neuropilin-1 / genetics
  • Neuropilin-1 / metabolism*
  • Nuclear Proteins / agonists*
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Peptide Fragments / chemistry
  • Peptide Fragments / genetics
  • Peptide Fragments / metabolism
  • Protein Interaction Domains and Motifs
  • Protein Transport
  • Recombinant Fusion Proteins / metabolism
  • Signal Transduction*
  • Zinc Finger Protein Gli2


  • GLI2 protein, human
  • Hedgehog Proteins
  • Kruppel-Like Transcription Factors
  • Nuclear Proteins
  • Peptide Fragments
  • Recombinant Fusion Proteins
  • Zinc Finger Protein Gli2
  • enhanced green fluorescent protein
  • Neuropilin-1
  • Green Fluorescent Proteins