@article{LisowskaRoedelManetetal.2018, author = {Lisowska, Justyna and R{\"o}del, Claudia Jasmin and Manet, Sandra and Miroshnikova, Yekaterina A. and Boyault, Cyril and Planus, Emmanuelle and De Mets, Richard and Lee, Hsiao-Hui and Destaing, Olivier and Mertani, Hichem and Boulday, Gwenola and Tournier-Lasserve, Elisabeth and Balland, Martial and Abdelilah-Seyfried, Salim and Albiges-Rizo, Corinne and Faurobert, Eva}, title = {The CCM1-CCM2 complex controls complementary functions of ROCK1 and ROCK2 that are required for endothelial integrity}, series = {Journal of cell science}, volume = {131}, journal = {Journal of cell science}, number = {15}, publisher = {Company biologists LTD}, address = {Cambridge}, issn = {0021-9533}, doi = {10.1242/jcs.216093}, pages = {15}, year = {2018}, abstract = {Endothelial integrity relies on a mechanical crosstalk between intercellular and cell-matrix interactions. This crosstalk is compromised in hemorrhagic vascular lesions of patients carrying loss-of-function mutations in cerebral cavernous malformation (CCM) genes. RhoA/ROCK-dependent cytoskeletal remodeling is central to the disease, as it causes unbalanced cell adhesion towards increased cell-extracellular matrix adhesions and destabilized cell-cell junctions. This study reveals that CCM proteins directly orchestrate ROCK1 and ROCK2 complementary roles on the mechanics of the endothelium. CCM proteins act as a scaffold, promoting ROCK2 interactions with VE-cadherin and limiting ROCK1 kinase activity. Loss of CCM1 (also known as KRIT1) produces excessive ROCK1-dependent actin stress fibers and destabilizes intercellular junctions. Silencing of ROCK1 but not ROCK2 restores the adhesive and mechanical homeostasis of CCM1 and CCM2-depleted endothelial monolayers, and rescues the cardiovascular defects of ccm1 mutant zebrafish embryos. Conversely, knocking down Rock2 but not Rock1 in wild-type zebrafish embryos generates defects reminiscent of the ccm1 mutant phenotypes. Our study uncovers the role of the CCM1-CCM2 complex in controlling ROCK1 and ROCK2 to preserve endothelial integrity and drive heart morphogenesis. Moreover, it solely identifies the ROCK1 isoform as a potential therapeutic target for the CCM disease.}, language = {en} } @article{OttenKnoxBouldayetal.2018, author = {Otten, Cecile and Knox, Jessica and Boulday, Gwenola and Eymery, Mathias and Haniszewski, Marta and Neuenschwander, Martin and Radetzki, Silke and Vogt, Ingo and Haehn, Kristina and De Luca, Coralie and Cardoso, Cecile and Hamad, Sabri and Igual Gil, Carla and Roy, Peter and Albiges-Rizo, Corinne and Faurobert, Eva and von Kries, Jens P. and Campillos, Monica and Tournier-Lasserve, Elisabeth and Derry, William Brent and Abdelilah-Seyfried, Salim}, title = {Systematic pharmacological screens uncover novel pathways involved in cerebral cavernous malformations}, series = {EMBO molecular medicine}, volume = {10}, journal = {EMBO molecular medicine}, number = {10}, publisher = {Wiley}, address = {Hoboken}, issn = {1757-4676}, doi = {10.15252/emmm.201809155}, pages = {17}, year = {2018}, abstract = {Cerebral cavernous malformations (CCMs) are vascular lesions in the central nervous system causing strokes and seizures which currently can only be treated through neurosurgery. The disease arises through changes in the regulatory networks of endothelial cells that must be comprehensively understood to develop alternative, non-invasive pharmacological therapies. Here, we present the results of several unbiased small-molecule suppression screens in which we applied a total of 5,268 unique substances to CCM mutant worm, zebrafish, mouse, or human endothelial cells. We used a systems biology-based target prediction tool to integrate the results with the whole-transcriptome profile of zebrafish CCM2 mutants, revealing signaling pathways relevant to the disease and potential targets for small-molecule-based therapies. We found indirubin-3-monoxime to alleviate the lesion burden in murine preclinical models of CCM2 and CCM3 and suppress the loss-of-CCM phenotypes in human endothelial cells. Our multi-organism-based approach reveals new components of the CCM regulatory network and foreshadows novel small-molecule-based therapeutic applications for suppressing this devastating disease in patients.}, language = {en} } @article{BornhorstAbdelilahSeyfried2021, author = {Bornhorst, Dorothee and Abdelilah-Seyfried, Salim}, title = {Strong as a Hippo's Heart: Biomechanical Hippo Signaling During Zebrafish Cardiac Development}, series = {Frontiers in Cell and Developmental Biology}, volume = {9}, journal = {Frontiers in Cell and Developmental Biology}, publisher = {Frontiers Media}, address = {Lausanne, Schweiz}, issn = {2296-634X}, doi = {10.3389/fcell.2021.731101}, pages = {1 -- 10}, year = {2021}, abstract = {The heart is comprised of multiple tissues that contribute to its physiological functions. During development, the growth of myocardium and endocardium is coupled and morphogenetic processes within these separate tissue layers are integrated. Here, we discuss the roles of mechanosensitive Hippo signaling in growth and morphogenesis of the zebrafish heart. Hippo signaling is involved in defining numbers of cardiac progenitor cells derived from the secondary heart field, in restricting the growth of the epicardium, and in guiding trabeculation and outflow tract formation. Recent work also shows that myocardial chamber dimensions serve as a blueprint for Hippo signaling-dependent growth of the endocardium. Evidently, Hippo pathway components act at the crossroads of various signaling pathways involved in embryonic zebrafish heart development. Elucidating how biomechanical Hippo signaling guides heart morphogenesis has direct implications for our understanding of cardiac physiology and pathophysiology.}, language = {en} } @article{MuenchAbdelilahSeyfried2021, author = {M{\"u}nch, Juliane and Abdelilah-Seyfried, Salim}, title = {Sensing and responding of cardiomyocytes to changes of tissue stiffness in the diseased heart}, series = {Frontiers in cell developmental biology}, volume = {9}, journal = {Frontiers in cell developmental biology}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {2296-634X}, doi = {10.3389/fcell.2021.642840}, pages = {13}, year = {2021}, abstract = {Cardiomyocytes are permanently exposed to mechanical stimulation due to cardiac contractility. Passive myocardial stiffness is a crucial factor, which defines the physiological ventricular compliance and volume of diastolic filling with blood. Heart diseases often present with increased myocardial stiffness, for instance when fibrotic changes modify the composition of the cardiac extracellular matrix (ECM). Consequently, the ventricle loses its compliance, and the diastolic blood volume is reduced. Recent advances in the field of cardiac mechanobiology revealed that disease-related environmental stiffness changes cause severe alterations in cardiomyocyte cellular behavior and function. Here, we review the molecular mechanotransduction pathways that enable cardiomyocytes to sense stiffness changes and translate those into an altered gene expression. We will also summarize current knowledge about when myocardial stiffness increases in the diseased heart. Sophisticated in vitro studies revealed functional changes, when cardiomyocytes faced a stiffer matrix. Finally, we will highlight recent studies that described modulations of cardiac stiffness and thus myocardial performance in vivo. Mechanobiology research is just at the cusp of systematic investigations related to mechanical changes in the diseased heart but what is known already makes way for new therapeutic approaches in regenerative biology.}, language = {en} } @article{RenzOttenFaurobertetal.2015, author = {Renz, Marc and Otten, Cecile and Faurobert, Eva and Rudolph, Franziska and Zhu, Yuan and Boulday, Gwenola and Duchene, Johan and Mickoleit, Michaela and Dietrich, Ann-Christin and Ramspacher, Caroline and Steed, Emily and Manet-Dupe, Sandra and Benz, Alexander and Hassel, David and Vermot, Julien and Huisken, Jan and Tournier-Lasserve, Elisabeth and Felbor, Ute and Sure, Ulrich and Albiges-Rizo, Corinne and Abdelilah-Seyfried, Salim}, title = {Regulation of beta 1 Integrin-Klf2-Mediated angiogenesis by CCM proteins}, series = {Developmental cell}, volume = {32}, journal = {Developmental cell}, number = {2}, publisher = {Cell Press}, address = {Cambridge}, issn = {1534-5807}, doi = {10.1016/j.devcel.2014.12.016}, pages = {181 -- 190}, year = {2015}, abstract = {Mechanotransduction pathways are activated in response to biophysical stimuli during the development or homeostasis of organs and tissues. In zebrafish, the blood-flow-sensitive transcription factor Klf2a promotes VEGF-dependent angiogenesis. However, the means by which the Klf2a mechanotransduction pathway is regulated to prevent continuous angiogenesis remain unknown. Here we report that the upregulation of klf2 mRNA causes enhanced egfl7 expression and angiogenesis signaling, which underlies cardiovascular defects associated with the loss of cerebral cavernous malformation (CCM) proteins in the zebrafish embryo. Using CCM-protein-depleted human umbilical vein endothelial cells, we show that the misexpression of KLF2 mRNA requires the extracellular matrix-binding receptor beta 1 integrin and occurs in the absence of blood flow. Downregulation of beta 1 integrin rescues ccm mutant cardiovascular malformations in zebrafish. Our work reveals a beta 1 integrin-Klf2-Egfl7-signaling pathway that is tightly regulated by CCM proteins. This regulation prevents angiogenic overgrowth and ensures the quiescence of endothelial cells.}, language = {en} } @article{MerksSwinarskiMeyeretal.2018, author = {Merks, Anne Margarete and Swinarski, Marie and Meyer, Alexander Matthias and M{\"u}ller, Nicola Victoria and {\"O}zcan, Ismail and Donat, Stefan and Burger, Alexa and Gilbert, Stephen and Mosimann, Christian and Abdelilah-Seyfried, Salim and Panakova, Daniela}, title = {Planar cell polarity signalling coordinates heart tube remodelling through tissue-scale polarisation of actomyosin activity}, series = {Nature Communications}, volume = {9}, journal = {Nature Communications}, publisher = {Nature Publ. Group}, address = {London}, issn = {2041-1723}, doi = {10.1038/s41467-018-04566-1}, pages = {15}, year = {2018}, abstract = {Development of a multiple-chambered heart from the linear heart tube is inherently linked to cardiac looping. Although many molecular factors regulating the process of cardiac chamber ballooning have been identified, the cellular mechanisms underlying the chamber formation remain unclear. Here, we demonstrate that cardiac chambers remodel by cell neighbour exchange of cardiomyocytes guided by the planar cell polarity (PCP) pathway triggered by two non-canonical Wnt ligands, Wnt5b and Wnt11. We find that PCP signalling coordinates the localisation of actomyosin activity, and thus the efficiency of cell neighbour exchange. On a tissue-scale, PCP signalling planar-polarises tissue tension by restricting the actomyosin contractility to the apical membranes of outflow tract cells. The tissue-scale polarisation of actomyosin contractility is required for cardiac looping that occurs concurrently with chamber ballooning. Taken together, our data reveal that instructive PCP signals couple cardiac chamber expansion with cardiac looping through the organ-scale polarisation of actomyosin-based tissue tension.}, language = {en} } @article{CuiSchlesingerSchoenhalsetal.2016, author = {Cui, Huanhuan and Schlesinger, Jenny and Schoenhals, Sophia and Toenjes, Martje and Dunkel, Ilona and Meierhofer, David and Cano, Elena and Schulz, Kerstin and Berger, Michael F. and Haack, Timm and Abdelilah-Seyfried, Salim and Bulyk, Martha L. and Sauer, Sascha and Sperling, Silke R.}, title = {Phosphorylation of the chromatin remodeling factor DPF3a induces cardiac hypertrophy through releasing HEY repressors from DNA}, series = {Nucleic acids research}, volume = {44}, journal = {Nucleic acids research}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0305-1048}, doi = {10.1093/nar/gkv1244}, pages = {2538 -- 2553}, year = {2016}, abstract = {DPF3 (BAF45c) is a member of the BAF chromatin remodeling complex. Two isoforms have been described, namely DPF3a and DPF3b. The latter binds to acetylated and methylated lysine residues of histones. Here, we elaborate on the role of DPF3a and describe a novel pathway of cardiac gene transcription leading to pathological cardiac hypertrophy. Upon hypertrophic stimuli, casein kinase 2 phosphorylates DPF3a at serine 348. This initiates the interaction of DPF3a with the transcriptional repressors HEY, followed by the release of HEY from the DNA. Moreover, BRG1 is bound by DPF3a, and is thus recruited to HEY genomic targets upon interaction of the two components. Consequently, the transcription of downstream targets such as NPPA and GATA4 is initiated and pathological cardiac hypertrophy is established. In human, DPF3a is significantly up-regulated in hypertrophic hearts of patients with hypertrophic cardiomyopathy or aortic stenosis. Taken together, we show that activation of DPF3a upon hypertrophic stimuli switches cardiac fetal gene expression from being silenced by HEY to being activated by BRG1. Thus, we present a novel pathway for pathological cardiac hypertrophy, whose inhibition is a long-term therapeutic goal for the treatment of the course of heart failure.}, language = {en} } @article{LombardoHeiseMoghtadaeietal.2019, author = {Lombardo, Ver{\´o}nica A. and Heise, Melina and Moghtadaei, Motahareh and Bornhorst, Dorothee and M{\"a}nner, J{\"o}rg and Abdelilah-Seyfried, Salim}, title = {Morphogenetic control of zebrafish cardiac looping by Bmp signaling}, series = {Development : Company of Biologists}, volume = {146}, journal = {Development : Company of Biologists}, number = {22}, publisher = {The Company of Biologists Ltd}, address = {Cambridge}, issn = {0950-1991}, doi = {10.1242/dev.180091}, pages = {13}, year = {2019}, abstract = {Cardiac looping is an essential and highly conserved morphogenetic process that places the different regions of the developing vertebrate heart tube into proximity of their final topographical positions. High-resolution 4D live imaging of mosaically labelled cardiomyocytes reveals distinct cardiomyocyte behaviors that contribute to the deformation of the entire heart tube. Cardiomyocytes acquire a conical cell shape, which is most pronounced at the superior wall of the atrioventricular canal and contributes to S-shaped bending. Torsional deformation close to the outflow tract contributes to a torque-like winding of the entire heart tube between its two poles. Anisotropic growth of cardiomyocytes based on their positions reinforces S-shaping of the heart. During cardiac looping, bone morphogenetic protein pathway signaling is strongest at the future superior wall of the atrioventricular canal. Upon pharmacological or genetic inhibition of bone morphogenetic protein signaling, myocardial cells at the superior wall of the atrioventricular canal maintain cuboidal cell shapes and S-shaped bending is impaired. This description of cellular rearrangements and cardiac looping regulation may also be relevant for understanding the etiology of human congenital heart defects.}, language = {en} } @article{LombardoOttenAbdelilahSeyfried2015, author = {Lombardo, Veronica A. and Otten, Cecile and Abdelilah-Seyfried, Salim}, title = {Large-scale Zebrafish Embryonic Heart Dissection for Transcriptional Analysis}, series = {Journal of visualized experiments}, journal = {Journal of visualized experiments}, number = {95}, publisher = {JoVE}, address = {Cambridge}, issn = {1940-087X}, doi = {10.3791/52087}, pages = {7}, year = {2015}, abstract = {The zebrafish embryonic heart is composed of only a few hundred cells, representing only a small fraction of the entire embryo. Therefore, to prevent the cardiac transcriptome from being masked by the global embryonic transcriptome, it is necessary to collect sufficient numbers of hearts for further analyses. Furthermore, as zebrafish cardiac development proceeds rapidly, heart collection and RNA extraction methods need to be quick in order to ensure homogeneity of the samples. Here, we present a rapid manual dissection protocol for collecting functional/beating hearts from zebrafish embryos. This is an essential prerequisite for subsequent cardiac-specific RNA extraction to determine cardiac-specific gene expression levels by transcriptome analyses, such as quantitative real-time polymerase chain reaction (RT-qPCR). The method is based on differential adhesive properties of the zebrafish embryonic heart compared with other tissues; this allows for the rapid physical separation of cardiac from extracardiac tissue by a combination of fluidic shear force disruption, stepwise filtration and manual collection of transgenic fluorescently labeled hearts.}, language = {en} } @article{DonatLourencoPaolinietal.2018, author = {Donat, Stefan and Lourenco, Marta Sofia Rocha and Paolini, Alessio and Otten, Cecile and Renz, Marc and Abdelilah-Seyfried, Salim}, title = {Heg1 and Ccm1/2 proteins control endocardial mechanosensitivity during zebrafish valvulogenesis}, series = {eLife}, volume = {7}, journal = {eLife}, publisher = {eLife Sciences Publications}, address = {Cambridge}, issn = {2050-084X}, doi = {10.7554/eLife.28939}, pages = {22}, year = {2018}, abstract = {Endothelial cells respond to different levels of fluid shear stress through adaptations of their mechanosensitivity. Currently, we lack a good understanding of how this contributes to sculpting of the cardiovascular system. Cerebral cavernous malformation (CCM) is an inherited vascular disease that occurs when a second somatic mutation causes a loss of CCM1/KRIT1, CCM2, or CCM3 proteins. Here, we demonstrate that zebrafish Krit1 regulates the formation of cardiac valves. Expression of heg1, which encodes a binding partner of Krit1, is positively regulated by blood-flow. In turn, Heg1 stabilizes levels of Krit1 protein, and both Heg1 and Krit1 dampen expression levels of klf2a, a major mechanosensitive gene. Conversely, loss of Krit1 results in increased expression of klf2a and notch1b throughout the endocardium and prevents cardiac valve leaflet formation. Hence, the correct balance of blood-flow-dependent induction and Krit1 protein mediated repression of klf2a and notch1b ultimately shapes cardiac valve leaflet morphology.}, language = {en} }