Standard

Distinct roles of nonmuscle myosin II isoforms in the regulation of mouse hepatic stellate cell contraction and migration. / Liu, Zhenan; Reynaert, Hendrik; Van Rossen, Elke; Van Grunsven, Leonardus; Schroyen, Ben; Timmermans, Jean-Pierre; Geerts, Albert.

The Belgian Week of Gastroenterology. 2009.

Research output: Chapter in Book/Report/Conference proceedingMeeting abstract (Book)

Harvard

APA

Vancouver

Author

BibTeX

@inbook{34f8261377224d5980c3c7240b4b60b0,
title = "Distinct roles of nonmuscle myosin II isoforms in the regulation of mouse hepatic stellate cell contraction and migration.",
abstract = "Background: Contraction and migration of hepatic stellate cells (HSC) during hepatic injury is essential for wound-healing, liver fibrosis and portal hypertension. Aims: To investigate the role of nonmuscle myosin II (NMMHC-II) isoforms in mouse HSC. Methods: First all, we identified which NMMHC-II(s) is expressed in HSC by QRT-PCR and Western blot. Then their subcellular localization was visualized by immunofluorescence and/or confocal microscopy after immunofluorescence staining. The interaction with actin isoforms was explored by dual-immunostaining and further conformed by co-immunopericiptation. Under the condition of isoform-specific siRNA gene silencing or treatment with chemical inhibitors, morphological and functional assays were performed. Changes were visualized with phase contrast microscopy. ET-1-induced contractile force generation was examined by collagen gel contraction and silicone wrinkle formation assay. Intracellular Ca2+ increase induced by ET-1stimulation was measured using Fluo-4. Cell migration was evaluated using the 'wound healing' assay. Results: NMMHC-IIA and -IIB are expressed in cultured HSC at both mRNA and protein level. NMMHC-IIA mRNA and protein levels were roughly constant. It was located in the subcortical area of quiescent HSC and colocalized with ?-SMA in stress fibers in activated HSC. Knockdown of NMMHC-IIA by siRNA decreased cell size, stress fibers and vinculin-containing focal adhesion. Knockdown of NMMHC-IIA completely impaired wrinkle formation on silicone substrate, and also blocked intracellular [Ca2+] release response to ET-1, but accelerated wound-induced cell migration. NMMHC-IIB was upregulated at both mRNA and protein levels. It was present in cytoplasmic processes of quiescent HSC, lamellipodia and cytoplasm in activated HSC. Colocalization of NMMHC-IIB and ?-actin was observed in the leading edge of lamellipodia. We also found expansion of ?-tubulin in lamellipodia (but not the leading edge) following spreading of the leading edge. Knockdown of NMMHC-IIB by siRNA decreased the formation of lamellipodia, impaired expansion of ?-tubulin in lamellipodia, and slowed down cell migration. We did not observe a significant effect of NMMHC-IIB on stress-fiber formation, cell contraction and intracellular Ca2+ release. Conclusions: myosin IIA and IIB are differentially expressed and localized in mHSC. They play distinct and complementary roles: myosin IIA controls cell body, focal adhesions and cell contraction by regulating stress-fiber formation which contain myosin IIA and ?-SMA. Myosin IIB mediates lamellipodia spreading and cell migration by distribution of ?-actin in the leading edge and by inducing ?-tubulin-expansion in lamellipodia.",
keywords = "Myosin II isoforms, contraction and migration, HSC",
author = "Zhenan Liu and Hendrik Reynaert and {Van Rossen}, Elke and {Van Grunsven}, Leonardus and Ben Schroyen and Jean-Pierre Timmermans and Albert Geerts",
year = "2009",
month = "2",
language = "English",
booktitle = "The Belgian Week of Gastroenterology",

}

RIS

TY - CHAP

T1 - Distinct roles of nonmuscle myosin II isoforms in the regulation of mouse hepatic stellate cell contraction and migration.

AU - Liu, Zhenan

AU - Reynaert, Hendrik

AU - Van Rossen, Elke

AU - Van Grunsven, Leonardus

AU - Schroyen, Ben

AU - Timmermans, Jean-Pierre

AU - Geerts, Albert

PY - 2009/2

Y1 - 2009/2

N2 - Background: Contraction and migration of hepatic stellate cells (HSC) during hepatic injury is essential for wound-healing, liver fibrosis and portal hypertension. Aims: To investigate the role of nonmuscle myosin II (NMMHC-II) isoforms in mouse HSC. Methods: First all, we identified which NMMHC-II(s) is expressed in HSC by QRT-PCR and Western blot. Then their subcellular localization was visualized by immunofluorescence and/or confocal microscopy after immunofluorescence staining. The interaction with actin isoforms was explored by dual-immunostaining and further conformed by co-immunopericiptation. Under the condition of isoform-specific siRNA gene silencing or treatment with chemical inhibitors, morphological and functional assays were performed. Changes were visualized with phase contrast microscopy. ET-1-induced contractile force generation was examined by collagen gel contraction and silicone wrinkle formation assay. Intracellular Ca2+ increase induced by ET-1stimulation was measured using Fluo-4. Cell migration was evaluated using the 'wound healing' assay. Results: NMMHC-IIA and -IIB are expressed in cultured HSC at both mRNA and protein level. NMMHC-IIA mRNA and protein levels were roughly constant. It was located in the subcortical area of quiescent HSC and colocalized with ?-SMA in stress fibers in activated HSC. Knockdown of NMMHC-IIA by siRNA decreased cell size, stress fibers and vinculin-containing focal adhesion. Knockdown of NMMHC-IIA completely impaired wrinkle formation on silicone substrate, and also blocked intracellular [Ca2+] release response to ET-1, but accelerated wound-induced cell migration. NMMHC-IIB was upregulated at both mRNA and protein levels. It was present in cytoplasmic processes of quiescent HSC, lamellipodia and cytoplasm in activated HSC. Colocalization of NMMHC-IIB and ?-actin was observed in the leading edge of lamellipodia. We also found expansion of ?-tubulin in lamellipodia (but not the leading edge) following spreading of the leading edge. Knockdown of NMMHC-IIB by siRNA decreased the formation of lamellipodia, impaired expansion of ?-tubulin in lamellipodia, and slowed down cell migration. We did not observe a significant effect of NMMHC-IIB on stress-fiber formation, cell contraction and intracellular Ca2+ release. Conclusions: myosin IIA and IIB are differentially expressed and localized in mHSC. They play distinct and complementary roles: myosin IIA controls cell body, focal adhesions and cell contraction by regulating stress-fiber formation which contain myosin IIA and ?-SMA. Myosin IIB mediates lamellipodia spreading and cell migration by distribution of ?-actin in the leading edge and by inducing ?-tubulin-expansion in lamellipodia.

AB - Background: Contraction and migration of hepatic stellate cells (HSC) during hepatic injury is essential for wound-healing, liver fibrosis and portal hypertension. Aims: To investigate the role of nonmuscle myosin II (NMMHC-II) isoforms in mouse HSC. Methods: First all, we identified which NMMHC-II(s) is expressed in HSC by QRT-PCR and Western blot. Then their subcellular localization was visualized by immunofluorescence and/or confocal microscopy after immunofluorescence staining. The interaction with actin isoforms was explored by dual-immunostaining and further conformed by co-immunopericiptation. Under the condition of isoform-specific siRNA gene silencing or treatment with chemical inhibitors, morphological and functional assays were performed. Changes were visualized with phase contrast microscopy. ET-1-induced contractile force generation was examined by collagen gel contraction and silicone wrinkle formation assay. Intracellular Ca2+ increase induced by ET-1stimulation was measured using Fluo-4. Cell migration was evaluated using the 'wound healing' assay. Results: NMMHC-IIA and -IIB are expressed in cultured HSC at both mRNA and protein level. NMMHC-IIA mRNA and protein levels were roughly constant. It was located in the subcortical area of quiescent HSC and colocalized with ?-SMA in stress fibers in activated HSC. Knockdown of NMMHC-IIA by siRNA decreased cell size, stress fibers and vinculin-containing focal adhesion. Knockdown of NMMHC-IIA completely impaired wrinkle formation on silicone substrate, and also blocked intracellular [Ca2+] release response to ET-1, but accelerated wound-induced cell migration. NMMHC-IIB was upregulated at both mRNA and protein levels. It was present in cytoplasmic processes of quiescent HSC, lamellipodia and cytoplasm in activated HSC. Colocalization of NMMHC-IIB and ?-actin was observed in the leading edge of lamellipodia. We also found expansion of ?-tubulin in lamellipodia (but not the leading edge) following spreading of the leading edge. Knockdown of NMMHC-IIB by siRNA decreased the formation of lamellipodia, impaired expansion of ?-tubulin in lamellipodia, and slowed down cell migration. We did not observe a significant effect of NMMHC-IIB on stress-fiber formation, cell contraction and intracellular Ca2+ release. Conclusions: myosin IIA and IIB are differentially expressed and localized in mHSC. They play distinct and complementary roles: myosin IIA controls cell body, focal adhesions and cell contraction by regulating stress-fiber formation which contain myosin IIA and ?-SMA. Myosin IIB mediates lamellipodia spreading and cell migration by distribution of ?-actin in the leading edge and by inducing ?-tubulin-expansion in lamellipodia.

KW - Myosin II isoforms

KW - contraction and migration

KW - HSC

M3 - Meeting abstract (Book)

BT - The Belgian Week of Gastroenterology

ER -

ID: 1841275