Which of the following statements is incorrect about the Hedgehog signaling pathway?
1
The presence of Hedgehog ligand prevents the Patched receptor from inhibiting Smoothened, allowing the pathway to activate and signal the cell to transcribe target genes
2
Smoothened acts as a downstream inhibitor in the Hedgehog pathway, directly inhibiting the transcription of target genes when the Hedgehog ligand is absent.
3
Activation of the Hedgehog pathway can lead to the transcription of genes involved in cell differentiation, indicating its vital role in the developmental patterning of tissues and organs.
4
In diseases such as basal cell carcinoma and medulloblastoma, aberrations in the Hedgehog signaling can contribute to malignancy due to unregulated cell proliferation and growth.