Tectonic-1 (TCTN1)

Part of the tectonic-like complex, a complex localized in the transition zone of primary cilia and acting as a barrier which prevents diffusion of transmembrane proteins between the cilia and plasma membranes. Regulator of Hedgehog (Hh), required for both activation and inhibition of the Hh pathway in the patterning of the neural tube.

During neural tube development, it's needed for formation of the most ventral cell types and for full Hh pathway activation. Functions in Hh signal transduction to fully activate the pathway in the presence of elevated Hh levels and to repress the pathway in the absence of Hh signals.