The Rho Guanine Nucleotide Exchange Factor DRhoGEF2 Is a Genetic Modifier of the PI3K Pathway in Drosophila
Authors: Tak Mak
Richard Binari
Vuk Stambolic
Ying-Ju Chang
Helen McNeill
Armen Manoukian
Lily Zhou
Journal: PLoS ONE (2016)
Discipline: Multidisciplinary
Keywords: insulin/IGF-1 signaling pathway; Drosophila; PTEN; PI3-kinase; genetic screen
Affiliations: Princess Margaret Cancer Center/University Health Network, Toronto, Ontario, Canada., Department of Medical Biophysics, University of Toronto, Toronto, Canada., Lunenfeld-Tanenbaum Research Institute/Mount Sinai Hospital, Toronto, Ontario, Canada., Department of Molecular Genetics, University of Toronto, Toronto, Canada.

Abstract:  The insulin/IGF-1 signaling pathway mediates various physiological processes associated with human health. Components of this pathway are highly conserved throughout eukaryotic evolution. In Drosophila, the PTEN ortholog and its mammalian counterpart downregulate insulin/IGF signaling by antagonizing the PI3-kinase function. From a dominant loss-of-function genetic screen, we discovered that mutations of a Dbl-family member, the guanine nucleotide exchange factor DRhoGEF2 (DRhoGEF22(l)04291), suppressed the PTEN-overexpression eye phenotype. dAkt/dPKB phosphorylation, a measure of PI3K signaling pathway activation, increased in the eye discs from the heterozygous DRhoGEF2 wandering third instar larvae. Overexpression of DRhoGEF2, and it's functional mammalian ortholog PDZ-RhoGEF (ArhGEF11), at various stages of eye development, resulted in both dPKB/Akt-dependent and -independent phenotypes, reflecting the complexity in the crosstalk between PI3K and Rho signaling in Drosophila. 

Retracted: No

PubPeer comments:
 Figure 5H. Plot duplication.  , 
 Figure 6B. Plot duplication.  , 
 #2 Dear Dr. Eumenopis, Thank you very much for your comments on our article related to possible duplicated images. I am the first author of this paper and with the permission from the senior authors Dr. Zhu and Dr. Shen, I prepare the following response to your inquiry. We have carefully checked the manuscript and the raw data immediately upon receiving your comment, and found that the mentioned images have indeed been misplaced in Figure 1 and Figure 4a. We sincerely apologize for our mistakes in the image preparation and we have would like to replace these with the original correct images as detailed below. 1. In Figure 1, CD68 immunostaining in MI tissues from KO (day 3) was careless mixture with MI tissues from KO (day 8). Since all the IHC data in Figure 1 was processing at the same time, IHC layer of MI tissues from KO mice (day 3) was unintentionally confused with the original layer in MI tissues from KO mice (day 8) during images processing, resulting in unconscious deletion of the real layer in MI tissues from KO mice (day 8). We have corrected it and provided the original photos. We immediately submitted a correction, and other repeat photos in group of MI tissues from KO mice (day 8) to the editorial office. On a positive note, it was not contradictory to our finding that the NaHS rescued the decrease of infiltrating macrophages caused by CSE depletion, and promoted macrophage infiltration in the early of MI. Erratum Figure 1:  2. In Figure 4a, the transwell image of PF573228+NaHS was overlapped by the NSC23766+NaHS group. During the processing of transwell images, PF573228+NaHS group was unintentionally confused with NSC23766+NaHS group, making them mixed with each other in the layers processing of all the images in Figure 4a. Herein, we have corrected image of PF573228+NaHS and provided the original photos. We immediately submitted a correction and another set of migration ability to verify the effect of PF573228 during NaHS treatment to the editorial office. On a positive note, statistical analysis in Figure 4a is unchanged, which also confirm that the migration of RAW264.7 cells accelerated by NaHS were inhibited by PF573228. Erratum Figure 4a:  Thank you again for your interests in our works. After received your comments and realized our mistakes, we immediately contacted the editorial office to inquiry about the process to make the necessary corrections by issuing a corrigendum. We will do our best to review all current work and publication process bysetting up a new protocol for image processing to minimize the impact of these errors and prevent it from happening again. Sincerely, Lei Miao, Ph.D E-mail: miaoleimolly@126.com , 
 Dear Dr. Eumenopis, Thank you very much for your comments on our article related to possible duplicated images. I am the first author of this paper and on behave of the senior authors Dr. Zhu and Dr. Shen. I prepare the following response to your inquiry with our highest priority. We have carefully inspected the manuscript and the raw data immediately upon receiving your comment, and found that the mentioned images have indeed been misplaced in Fig.5B and Fig.6H during the preparation of our manuscript. we have would like to replace these with the original correct images as detailed below. 1. In Fig.5H, flow cytometry analysis of F4 80+CD206+ WT-BMMs with NaSH treatment was careless mixture with at Orlistate+NaSH group. Because flow cytometry layer of NaSH-treated images was high similar with NaSH+Orl-treated images, leading to unintentionally confused with each other during images processing, resulting in unconscious deletion NaSH+Orl-treated images. We have corrected it and provided the original photos. We immediately submitted a correction, and another 2-3 repeats to the editorial office. On a positive note, statistical analysis in figure 5I is unchanged, which also confirmed our data that Orlistate effectively inhibited NaSH-induced F4 80+CD206+ BMMs. Erratum Fig.5H: 2. In Fig.6B, mitoFluor Green staining of KO-mitochondrial with NaHS treatment was overlapped with WT-mitochondrial with NaSH treatment in Fig.6B. Because flow cytometry histogram of NaSH-treated WT-BMMs, as well as NaSH-treated KO-BMMs were similarity to some degree, making them mixed with each other in the layers processing of all the images in Fig.6B. Herein, we have corrected it and provided the original photos. We immediately submitted a correction and another another repeats to the editorial office, the result was also consistence with IF staining, and confirmed that NaSH increased mitochondrial staining both in WT and in CSE KO BMMs.Erratum Fig.6B:  Thank you again for your interests in our works. After pointing out this oversight of ours, we immediately contacted the editorial office to inquiry about the process to make the necessary corrections by issuing a corrigendum. We will do our best to review all current work and publication process bysetting up a new protocol for image processing to minimize the impact of these errors and prevent it from happening again. Sincerely, Lei Miao, Ph.D E-mail: miaoleimolly@126.com ,