The cytoskeletal protein Zyxin inhibits Shh signaling during the CNS patterning in Xenopus laevis through interaction with the transcription factor Gli1

Abstract

Zyxin is a cytoskeletal protein that controls cell movements by regulating actin filaments assembly, but it can also modulate gene expression owing to its interactions with the proteins involved in signaling cascades. Therefore, identification of proteins that interact with Zyxin in embryonic cells is a promising way to unravel mechanisms responsible for coupling of two major components of embryogenesis: morphogenetic movements and cell differentiation. Now we show that in Xenopus laevis embryos Zyxin can bind to and suppress activity of the primary effector of Sonic hedgehog (Shh) signaling cascade, the transcription factor Gli1. By using loss- and gain-of-function approaches, we demonstrate that Zyxin is essential for reduction of Shh signaling within the dorsal part of the neural tube of X. laevis embryo. Thus, our finding discloses a novel function of Zyxin in fine tuning of the central neural system patterning which is based on the ventral-to-dorsal gradient of Shh signaling.