CRISPR screens uncover genes that regulate target cell sensitivity to the morphogen Sonic Hedgehog
journal contributionposted on 2020-09-07, 11:35 authored by Ganesh V Pusapati, Jennifer H Kong, Bhaven B Patel, Arunkumar Krishnan, Andreas Sagner, Maia Kinnebrew, James Briscoe, L Aravind, Rajat Rohatgi
To uncover regulatory mechanisms in Hedgehog (Hh) signaling, we conducted genome-wide screens to identify positive and negative pathway components and validated top hits using multiple signaling and differentiation assays in two different cell types. Most positive regulators identified in our screens, including Rab34, Pdcl, and Tubd1, were involved in ciliary functions, confirming the central role for primary cilia in Hh signaling. Negative regulators identified included Megf8, Mgrn1, and an unannotated gene encoding a tetraspan protein we named Atthog. The function of these negative regulators converged on Smoothened (SMO), an oncoprotein that transduces the Hh signal across the membrane. In the absence of Atthog, SMO was stabilized at the cell surface and concentrated in the ciliary membrane, boosting cell sensitivity to the ligand Sonic Hedgehog (SHH) and consequently altering SHH-guided neural cell-fate decisions. Thus, we uncovered genes that modify the interpretation of morphogen signals by regulating protein-trafficking events in target cells.
CRISPR screenHedgehog signalingSmoothenedciliopathycongenital heart diseaseheterotaxymorphogen signalingneural tube patterningprimary ciliaprotein traffickingAnimalsCell MovementCiliaClustered Regularly Interspaced Short Palindromic RepeatsFluorescenceHedgehog ProteinsMembrane ProteinsMiceNIH 3T3 CellsNeuronsSignal TransductionSmoothened ReceptorBriscoe FC00105106 Biological Sciences11 Medical and Health SciencesDevelopmental Biology