Fibronectin-dependent tissue mechanics regulate the translation of segmentation clock oscillations into periodic somite formation

Somitogenesis starts with cyclic waves of expression of segmentation clock genes in the presomitic mesoderm (PSM) and culminates with periodic budding of somites in its anterior-most region. How cyclic clock gene expression is translated into timely morphological somite formation has remained unclea...

Full description

Saved in:
Bibliographic Details
Published inbioRxiv
Main Authors Patrícia Gomes De Almeida, Rifes, Pedro, Ana Patrícia Martins-Jesus, Pinheiro, Gonçalo G, Andrade, Raquel P, Thorsteinsdóttir, Sólveig
Format Paper
LanguageEnglish
Published Cold Spring Harbor Cold Spring Harbor Laboratory Press 31.12.2019
Subjects
Actomyosin
Clock gene
Contractility
Fibronectin
Gene expression
Kinases
Mechanical properties
Mechanotransduction
Mesoderm
Oscillations
Protein kinase
Segmentation
Somites
Somitogenesis
Online AccessGet full text

Cover

More Information
Summary:Somitogenesis starts with cyclic waves of expression of segmentation clock genes in the presomitic mesoderm (PSM) and culminates with periodic budding of somites in its anterior-most region. How cyclic clock gene expression is translated into timely morphological somite formation has remained unclear. A posterior to anterior gradient of increasing PSM tissue cohesion correlates with increasing fibronectin matrix complexity around the PSM, suggesting that fibronectin-dependent tissue mechanics may be involved in this transition. Here we address whether the mechanical properties of the PSM tissue play a role in regulating the pathway leading to cleft formation in the anterior PSM. We first interfered with cytoskeletal contractility in the chick PSM by disrupting actomyosin-mediated contractility directly or via Rho-associated protein kinase function. Then we perturbed fibronectin matrix accumulation around the PSM tissue by blocking integrin-fibronectin binding or fibronectin matrix assembly. All four treatments perturbed hairy1 and meso1 expression dynamics and resulted in defective somitic clefts. A model is presented where a gradient of fibronectin-dependent tissue mechanics participates in the PSM wavefront of maturation by ensuring the correct spatio-temporal conversion of cyclic segmentation clock gene expression into periodic somite formation. Footnotes * The text of the manuscript has been slightly revised.
DOI:10.1101/808121