title: αE-catenin regulates cell-cell adhesion and membrane blebbing during zebrafish epiboly.
abstract: αE-catenin is an actin-binding protein associated with the E-cadherin-based adherens junction that regulates cell-cell adhesion. Recent studies identified additional E-cadherin-independent roles of αE-catenin in regulating plasma membrane dynamics and cell migration. However, little is known about the roles of αE-catenin in these different cellular processes in vivo during early vertebrate development. Here, we examined the functions of αE-catenin in cell-cell adhesion, cell migration and plasma membrane dynamics during morphogenetic processes that drive epiboly in early Danio rerio (zebrafish) development. We show that depletion of αE-catenin caused a defect in radial intercalation that was associated with decreased cell-cell adhesion, in a similar manner to E-cadherin depletion. Depletion of αE-catenin also caused deep cells to have protracted plasma membrane blebbing, and a defect in plasma membrane recruitment of ERM proteins that are involved in controlling membrane-to-cortex attachment and membrane blebbing. Significantly, depletion of both E-cadherin and αE-catenin suppressed plasma membrane blebbing. We suggest that during radial intercalation the activities of E-cadherin and αE-catenin in the maintenance of membrane-to-cortex attachment are balanced, resulting in stabilization of cell-cell adhesion and suppression of membrane blebbing, thereby enabling proper radial intercalation.
authors.affiliation: Department of Biology, Stanford University, Stanford, CA 94304, USA. antonino.schepis@kcl.ac.uk
authors.forename: Antonino
authors.initials: A
authors.lastname: Schepis
authors.forename: Diane
authors.initials: D
authors.lastname: Sepich
authors.forename: W James
authors.initials: WJ
authors.lastname: Nelson
mesh_terms: D000818:Animals; D015820:Cadherins / Q000378:metabolism; D002448:Cell Adhesion; D002462:Cell Membrane / Q000378:metabolism*; D002465:Cell Movement; D004268:DNA-Binding Proteins / Q000378:metabolism; D009024:Morphogenesis; D015398:Signal Transduction; D014157:Transcription Factors / Q000378:metabolism; D015027:Zebrafish / Q000254:growth & development* / Q000378:metabolism; D029961:Zebrafish Proteins / Q000378:metabolism*; D051178:alpha Catenin / Q000378:metabolism*
chemical_list: D015820:Cadherins; D004268:DNA-Binding Proteins; D014157:Transcription Factors; D029961:Zebrafish Proteins; D051178:alpha Catenin; C513244:etv5b protein, zebrafish