Snail regulates Hippo signalling-mediated cell proliferation and tissue growth in Drosophila

Abstract

Snail (Sna) plays a pivotal role in epithelia-mesenchymal transition and cancer metastasis, yet its functions in normal tissue development remain elusive.Here, using Drosophila as amodel organism, we identified Sna as an essential regulator ofHippo signalling-mediated cell proliferation and tissue growth. First, Sna is necessary and sufficient for impaired Hippo signalling-induced cell proliferation and tissue overgrowth. Second, Sna is necessary and sufficient for the expression of Hippo pathway target genes. Third, genetic epistasis data indicate Sna acts downstream of Yki in the Hippo signalling. Finally, Sna is physiologically required for tissue growth in normal development. Mechanistically, Yki activates the transcription of sna, whose protein product binds to Scalloped (Sd) and promotes Sd-dependent cell proliferation. Thus, this study uncovered a previously unknown physiological function of Sna in normal tissue development and revealed the underlying mechanismby which Snamodulates Hippo signalling-mediated cell proliferation and tissue growth.