Mechanics of zebrafish epiboly: Tension-oriented cell divisions limit anisotropic tissue tension in epithelial spreading (Record no. 340548)

000 -LEADER
fixed length control field 03094ntm a22003137a 4500
003 - CONTROL NUMBER IDENTIFIER
control field AT-ISTA
005 - DATE AND TIME OF LATEST TRANSACTION
control field 20190813114304.0
008 - FIXED-LENGTH DATA ELEMENTS--GENERAL INFORMATION
fixed length control field 160531s2013 au ||||| m||| 00| 0 eng d
040 ## - CATALOGING SOURCE
Transcribing agency IST
100 ## - MAIN ENTRY--PERSONAL NAME
Personal name Campinho, Pedro
9 (RLIN) 2634
245 ## - TITLE STATEMENT
Title Mechanics of zebrafish epiboly: Tension-oriented cell divisions limit anisotropic tissue tension in epithelial spreading
260 ## - PUBLICATION, DISTRIBUTION, ETC. (IMPRINT)
Name of publisher, distributor, etc. IST Austria
Date of publication, distribution, etc. 2013
500 ## - GENERAL NOTE
General note Thesis
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note Biographical Sketch
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note List of Publications
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note Acknowledgments
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note Abstract
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note List of Tables
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note List of Figures
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note List of Abbreviations
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note 1 Introduction
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note 2 Materials and Methods
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note 3 Results
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note 4 Discussions and Conclusions
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note 5 References
505 ## - FORMATTED CONTENTS NOTE
Formatted contents note 6 Appendix
520 ## - SUMMARY, ETC.
Summary, etc. Epithelial spreading is a critical part of various developmental and wound repair processes. Here we use zebrafish epiboly as a model system to study the cellular and molecular mechanisms underlying the spreading of epithelial sheets. During zebrafish epiboly the enveloping cell layer (EVL), a simple squamous epithelium, spreads over the embryo to eventually cover the entire yolk cell by the end of gastrulation. The EVL leading edge is anchored through tight junctions to the yolk syncytial layer (YSL), where directly adjacent to the EVL margin a contractile actomyosin ring is formed that is thought to drive EVL epiboly. The prevalent view in the field was that the contractile ring exerts a pulling force on the EVL margin, which pulls the EVL towards the vegetal pole. However, how this force is generated and how it affects EVL morphology still remains elusive. Moreover, the cellular mechanisms mediating the increase in EVL surface area, while maintaining tissue integrity and function are still unclear. Here we show that the YSL actomyosin ring pulls on the EVL margin by two distinct force-generating mechanisms. One mechanism is based on contraction of the ring around its circumference, as previously proposed. The second mechanism is based on actomyosin retrogade flows, generating force through resistance against the substrate. The latter can function at any epiboly stage even in situations where the contraction-based mechanism is unproductive. Additionally, we demonstrate that during epiboly the EVL is subjected to anisotropic tension, which guides the orientation of EVL cell division along the main axis (animal-vegetal) of tension. The influence of tension in cell division orientation involves cell elongation and requires myosin-2 activity for proper spindle alignment. Strikingly, we reveal that tension-oriented cell divisions release anisotropic tension within the EVL and that in the absence of such divisions, EVL cells undergo ectopic fusions. We conclude that forces applied to the EVL by the action of the YSL actomyosin ring generate a tension anisotropy in the EVL that orients cell divisions, which in turn limit tissue tension increase thereby facilitating tissue spreading.
942 ## - ADDED ENTRY ELEMENTS (KOHA)
Source of classification or shelving scheme
Holdings
Withdrawn status Lost status Source of classification or shelving scheme Damaged status Not for loan Permanent Location Current Location Date acquired Barcode Date last seen Price effective from Koha item type
  Not Lost       Library Library 2016-05-31 AT-ISTA#001147 2018-11-06 2016-05-31 Book

Powered by Koha