The Hippo tumor-suppressor pathway regulates apical-domain size in parallel to tissue growth

• DOI: 10.1242/jcs.046482
• Publication Date: 2009-06-17T00:45:43Z
• Authors: Fisun Hamaratoglu; Kathleen Gajewski; Leticia Sansores-...; Clayton Morrison; Chunyao Tao; Georg Halder
• Keywords: Hippo signaling pathway; Merlin (protein); Cell polarity; FERM domain; Apical membrane

The Hippo tumor-suppressor pathway controls tissue growth in Drosophila and mammals by regulating cell proliferation apoptosis. includes the Fat cadherin, a transmembrane protein, which acts upstream of several other components that form kinase cascade culminates regulation gene expression through transcriptional coactivator Yorkie (Yki). Our previous work indicated Merlin (Mer) Expanded (Ex) are members act kinase. In contrast to this model, it was suggested Mer Ex primarily regulate membrane dynamics receptor trafficking, thereby affecting activity only indirectly. Here, we examined effects Mer, on size apical apical-basal polarity complexes. We found mer;ex double mutant imaginal disc cells have significantly increased levels determinants, such as Crb, aPKC Patj. These phenotypes were shared with mutations required Yki, indicating signal pathway. Interestingly, however, whereas Crb for accumulation proteins expansion domain observed mutants, its elimination did not reverse overgrowth phenotype warts cells. Therefore, signaling regulates complexes addition independently control function