PMID- 30440051 OWN - NLM STAT- MEDLINE DCOM- 20190416 LR - 20190416 IS - 1932-6203 (Electronic) IS - 1932-6203 (Linking) VI - 13 IP - 11 DP - 2018 TI - CRB3 and the FERM protein EPB41L4B regulate proliferation of mammary epithelial cells through the release of amphiregulin. PG - e0207470 LID - 10.1371/journal.pone.0207470 [doi] LID - e0207470 AB - Numerous observations have suggested a connection between the maintenance of cell polarity and control of cell proliferation; however, the mechanisms underlying these connections remain poorly understood. Here we found that ectopic expression of CRB3, which was previously shown to restore tight junctions and membrane polarity in MCF-10A cells, induced a hyperproliferative phenotype, with significantly enlarged acini in basement membrane culture, similar to structures induced by expression of proliferative oncogenes such as cyclinD1. We found that CRB3-induced proliferation is epidermal growth factor (EGF)-independent and occurs through a mechanism that involves secretion of the EGF-family ligand, amphiregulin (AREG). The increase in AREG secretion is associated with an increase in the number and size of both early and late endosomes. Both the proliferative and endocytic phenotypes associated with CRB3 expression require the FERM-binding domain (FBD) but not the PDZ-binding domain of CRB3, arguing that this proliferative phenotype is independent of the PDZ-dependent polarity signaling by CRB3. We identified the FBD-containing protein, EPB41L4B, as an essential mediator of CRB3-driven proliferation and observed that the CRB3-dependent changes in endocytic trafficking were also dependent on EPB41L4B. Taken together, these data reveal a previously uncharacterized role for CRB3 in regulating proliferation in mammalian cells that is associated with changes in the endocytic trafficking machinery. FAU - Walker, Stephanie J AU - Walker SJ AUID- ORCID: 0000-0002-6234-6846 AD - Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, United States of America. FAU - Selfors, Laura M AU - Selfors LM AD - Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, United States of America. FAU - Margolis, Ben L AU - Margolis BL AD - Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America. FAU - Brugge, Joan S AU - Brugge JS AD - Department of Cell Biology, Harvard Medical School, Boston, Massachusetts, United States of America. LA - eng PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't DEP - 20181115 PL - United States TA - PLoS One JT - PloS one JID - 101285081 RN - 0 (Amphiregulin) RN - 0 (CRB3 protein, human) RN - 0 (Cytoskeletal Proteins) RN - 0 (EPB41L4B protein, human) RN - 0 (Membrane Glycoproteins) RN - 0 (RNA, Small Interfering) RN - 136601-57-5 (Cyclin D1) SB - IM MH - Amphiregulin/biosynthesis/*genetics MH - Animals MH - Cell Line, Tumor MH - Cell Polarity/*genetics MH - Cell Proliferation/drug effects MH - Cyclin D1/genetics MH - Cytoskeletal Proteins/*genetics MH - Epithelial Cells/metabolism MH - FERM Domains/genetics MH - Gene Expression Regulation, Neoplastic MH - Humans MH - Mammary Glands, Human/drug effects/metabolism MH - Membrane Glycoproteins/*genetics MH - PDZ Domains/genetics MH - Phenotype MH - Protein Binding MH - RNA, Small Interfering/genetics PMC - PMC6237394 COIS- The authors have declared that no competing interests exist. EDAT- 2018/11/16 06:00 MHDA- 2019/04/17 06:00 PMCR- 2018/11/15 CRDT- 2018/11/16 06:00 PHST- 2018/08/17 00:00 [received] PHST- 2018/10/31 00:00 [accepted] PHST- 2018/11/16 06:00 [entrez] PHST- 2018/11/16 06:00 [pubmed] PHST- 2019/04/17 06:00 [medline] PHST- 2018/11/15 00:00 [pmc-release] AID - PONE-D-18-24317 [pii] AID - 10.1371/journal.pone.0207470 [doi] PST - epublish SO - PLoS One. 2018 Nov 15;13(11):e0207470. doi: 10.1371/journal.pone.0207470. eCollection 2018.