Bile canaliculi remodeling activates YAP via the actin cytoskeleton during liver regeneration.
Mol Syst Biol
; 16(2): e8985, 2020 02.
Article
em En
| MEDLINE
| ID: mdl-32090478
ABSTRACT
The mechanisms of organ size control remain poorly understood. A key question is how cells collectively sense the overall status of a tissue. We addressed this problem focusing on mouse liver regeneration. Using digital tissue reconstruction and quantitative image analysis, we found that the apical surface of hepatocytes forming the bile canalicular network expands concomitant with an increase in F-actin and phospho-myosin, to compensate an overload of bile acids. These changes are sensed by the Hippo transcriptional co-activator YAP, which localizes to apical F-actin-rich regions and translocates to the nucleus in dependence of the integrity of the actin cytoskeleton. This mechanism tolerates moderate bile acid fluctuations under tissue homeostasis, but activates YAP in response to sustained bile acid overload. Using an integrated biophysical-biochemical model of bile pressure and Hippo signaling, we explained this behavior by the existence of a mechano-sensory mechanism that activates YAP in a switch-like manner. We propose that the apical surface of hepatocytes acts as a self-regulatory mechano-sensory system that responds to critical levels of bile acids as readout of tissue status.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Canalículos Biliares
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Citoesqueleto de Actina
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Ácidos e Sais Biliares
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Proteínas de Ciclo Celular
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Hepatócitos
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Proteínas Adaptadoras de Transdução de Sinal
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Alemanha