Retraction Notice to: Dystroglycan and Perlecan Provide a Basal Cue Required for Epithelial Polarity during Energetic Stress

(Developmental Cell 16, 83–92; January 20, 2009) In following up the experiments reported in this paper, we have discovered that the polarity phenotypes ofDystroglycan and perlecan mutant clones under starvation conditions shown in Figures 4, 5, 6F, 6H, and 6J are the result of an artifact. We now believe that these panels do not represent real clones with a polarity phenotype, but rather false clones caused by a damage-induced artifact that creates patches of GFP-negative cells that mimic the appearance of a mutant clone with apical-basal polarity defects. Bona fide Dystroglycan and perlecanmutant clones marked using a different system do not show this phenotype, and thus our conclusion that they are required for the apical-basal polarity of the follicle cells under conditions of energetic stress is incorrect. We have described this damage-induced artifact in an article in Biology Open (Haack, T., Bergstralh, D., and St Johnston, D. (2013). Damage to the Drosophila follicle cell epithelium produces ‘‘false clones’’ with apparent polarity phenotypes. http://dx.doi.org/10.1242/bio. 20134671). We apologize for any inconvenience that this erroneous conclusion may have caused. The results pertaining to the characterization of null Dg alleles and their role in basal planar cell polarity and egg shape remain valid. In light of our new data, the results from the paper lead to the conclusion that neither Dg nor Dys has an essential role in follicle cell polarity.