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Current Topics in Developmental Biology 2021The pancreas of adult mammals displays a branched structure which transports digestive enzymes produced in the distal acini through a tree-like network of ducts into the... (Review)
Review
The pancreas of adult mammals displays a branched structure which transports digestive enzymes produced in the distal acini through a tree-like network of ducts into the duodenum. In contrast to several other branched organs, its branching patterns are not stereotypic. Moreover, the branches do not grow from dichotomic splitting of an initial stem but rather from the formation of microlumen in a mass of cells. These lumen progressively assemble into a hyperconnected network that refines into a tree by the time of birth. We review the cell remodeling events and the molecular mechanisms governing pancreas branching, as well as the role of the surrounding tissues in this process. Furthermore, we draw parallels with other branched organs such as the salivary and mammary gland.
Topics: Animals; Mammals; Morphogenesis; Organogenesis; Pancreas
PubMed: 33820626
DOI: 10.1016/bs.ctdb.2020.10.006 -
Small (Weinheim An Der Bergstrasse,... Feb 2022Embryonic morphogenesis is a biological process which depicts shape forming of tissues and organs during development. Unveiling the roles of mechanical forces generated,... (Review)
Review
Embryonic morphogenesis is a biological process which depicts shape forming of tissues and organs during development. Unveiling the roles of mechanical forces generated, transmitted, and regulated in cells and tissues through these processes is key to understanding the biophysical mechanisms governing morphogenesis. To this end, it is imperative to measure, simulate, and predict the regulation and control of these mechanical forces during morphogenesis. This article aims to provide a comprehensive review of the recent advances on mechanical properties of cells and tissues, generation of mechanical forces in cells and tissues, the transmission processes of these generated forces during cells and tissues, the tools and methods used to measure and predict these mechanical forces in vivo, in vitro, or in silico, and to better understand the corresponding regulation and control of generated forces. Understanding the biomechanics and mechanobiology of morphogenesis will not only shed light on the fundamental physical mechanisms underlying these concerted biological processes during normal development, but also uncover new information that will benefit biomedical research in preventing and treating congenital defects or tissue engineering and regeneration.
Topics: Biomechanical Phenomena; Biophysics; Embryonic Development; Morphogenesis
PubMed: 34837328
DOI: 10.1002/smll.202103466 -
Physical Biology Sep 2023Cells communicate with each other to jointly regulate cellular processes during cellular differentiation and tissue morphogenesis. This multiscale coordination arises... (Review)
Review
Cells communicate with each other to jointly regulate cellular processes during cellular differentiation and tissue morphogenesis. This multiscale coordination arises through the spatiotemporal activity of morphogens to pattern cell signaling and transcriptional factor activity. This coded information controls cell mechanics, proliferation, and differentiation to shape the growth and morphogenesis of organs. While many of the molecular components and physical interactions have been identified in key model developmental systems, there are still many unresolved questions related to the dynamics involved due to challenges in precisely perturbing and quantitatively measuring signaling dynamics. Recently, a broad range of synthetic optogenetic tools have been developed and employed to quantitatively define relationships between signal transduction and downstream cellular responses. These optogenetic tools can control intracellular activities at the single cell or whole tissue scale to direct subsequent biological processes. In this brief review, we highlight a selected set of studies that develop and implement optogenetic tools to unravel quantitative biophysical mechanisms for tissue growth and morphogenesis across a broad range of biological systems through the manipulation of morphogens, signal transduction cascades, and cell mechanics. More generally, we discuss how optogenetic tools have emerged as a powerful platform for probing and controlling multicellular development.
Topics: Optogenetics; Morphogenesis; Cell Communication; Signal Transduction; Biological Phenomena
PubMed: 37678266
DOI: 10.1088/1478-3975/acf7a1 -
WormBook : the Online Review of C.... Nov 2012The C. elegans hermaphrodite vulva is an established model system to study mechanisms of cell fate specification and tissue morphogenesis. The adult vulva is a tubular... (Review)
Review
The C. elegans hermaphrodite vulva is an established model system to study mechanisms of cell fate specification and tissue morphogenesis. The adult vulva is a tubular shaped organ composed of seven concentric toroids that arise from selective fusion between differentiated vulval progeny. The dorsal end of the vulval tubule is connected to the uterus via a multinucleate syncytium utse (uterine-seam) cell. The vulval tubule and utse are formed as a result of changes in morphogenetic processes such as cell polarity, adhesion, and invagination. A number of genes controlling these processes are conserved all the way up to human and function in similar developmental contexts. This makes it possible to extend the findings to other metazoan systems. Gene expression studies in the vulval and uterine cells have revealed the presence of regulatory networks specifying distinct cell fates. Thus, these two cell types serve as a good system to understand how gene networks confer unique cell identities both experimentally and computationally. This chapter focuses on morphogenetic processes during the formation of the vulva and its connection to uterus.
Topics: Animals; Body Patterning; Caenorhabditis elegans; Female; Morphogenesis; Uterus; Vulva
PubMed: 23208727
DOI: 10.1895/wormbook.1.152.1 -
The EMBO Journal Oct 2019Tissue morphogenesis in multicellular organisms is brought about by spatiotemporal coordination of mechanical and chemical signals. Extensive work on how mechanical... (Review)
Review
Tissue morphogenesis in multicellular organisms is brought about by spatiotemporal coordination of mechanical and chemical signals. Extensive work on how mechanical forces together with the well-established morphogen signalling pathways can actively shape living tissues has revealed evolutionary conserved mechanochemical features of embryonic development. More recently, attention has been drawn to the description of tissue material properties and how they can influence certain morphogenetic processes. Interestingly, besides the role of tissue material properties in determining how much tissues deform in response to force application, there is increasing theoretical and experimental evidence, suggesting that tissue material properties can abruptly and drastically change in development. These changes resemble phase transitions, pointing at the intriguing possibility that important morphogenetic processes in development, such as symmetry breaking and self-organization, might be mediated by tissue phase transitions. In this review, we summarize recent findings on the regulation and role of tissue material properties in the context of the developing embryo. We posit that abrupt changes of tissue rheological properties may have important implications in maintaining the balance between robustness and adaptability during embryonic development.
Topics: Animals; Biomechanical Phenomena; Cell Differentiation; Embryonic Development; Humans; Morphogenesis; Rheology; Signal Transduction
PubMed: 31512749
DOI: 10.15252/embj.2019102497 -
Current Opinion in Genetics &... Feb 2022Epithelial morphogenesis is guided by mechanical forces and biochemical signals that vary spatiotemporally. As many morphogenetic events are driven by rapid cellular... (Review)
Review
Epithelial morphogenesis is guided by mechanical forces and biochemical signals that vary spatiotemporally. As many morphogenetic events are driven by rapid cellular processes, understanding morphogenesis requires monitoring development in real time. Here, we discuss how live-imaging approaches can help identify morphogenetic mechanisms otherwise missed in static snapshots of development. We begin with a summary of live-imaging strategies, including recent advances that push the limits of spatiotemporal resolution and specimen size. We then describe recent efforts that employ live imaging to uncover morphogenetic mechanisms. We conclude by discussing how information collected from live imaging can be enhanced by genetically encoded biosensors and spatiotemporal perturbation techniques to determine the dynamics of patterning of developmental signals and their importance for guiding morphogenesis.
Topics: Mechanical Phenomena; Morphogenesis
PubMed: 34864332
DOI: 10.1016/j.gde.2021.10.007 -
Cells & Development Dec 2021The blastocyst has long been a hallmark system of study in developmental biology due to its importance in mammalian development and clinical relevance for assisted... (Review)
Review
The blastocyst has long been a hallmark system of study in developmental biology due to its importance in mammalian development and clinical relevance for assisted reproductive technologies. In recent years, the blastocyst is emerging as a system of study for mathematical modelling. In this review, we compile, to our knowledge, all models describing preimplantation development. Coupled with experiments, these models have provided insight regarding the morphogenesis and cell-fate specification throughout preimplantation development. In the case of cell-fate specification, theoretical models have provided mechanisms explaining how proportion of cell types are established and maintained when confronted to perturbations. For cell-shape based models, they have described quantitatively how mechanical forces sculpt the blastocyst and even predicted how morphogenesis could be manipulated. As theoretical biology develops, we believe the next critical stage in modelling involves an integration of cell fate and mechanics to provide integrative models of development at distinct spatiotemporal scales. We discuss how, building on a balanced base of mechanical and chemical models, the preimplantation embryo will play a key role in integrating these two faces of the same coin.
Topics: Animals; Blastocyst; Cell Differentiation; Embryonic Development; Mammals; Morphogenesis
PubMed: 34634520
DOI: 10.1016/j.cdev.2021.203752 -
Physiological Reviews Jan 2019The unique architecture of the mammalian lung is required for adaptation to air breathing at birth and thereafter. Understanding the cellular and molecular mechanisms... (Review)
Review
The unique architecture of the mammalian lung is required for adaptation to air breathing at birth and thereafter. Understanding the cellular and molecular mechanisms controlling its morphogenesis provides the framework for understanding the pathogenesis of acute and chronic lung diseases. Recent single-cell RNA sequencing data and high-resolution imaging identify the remarkable heterogeneity of pulmonary cell types and provides cell selective gene expression underlying lung development. We will address fundamental issues related to the diversity of pulmonary cells, to the formation and function of the mammalian lung, and will review recent advances regarding the cellular and molecular pathways involved in lung organogenesis. What cells form the lung in the early embryo? How are cell proliferation, migration, and differentiation regulated during lung morphogenesis? How do cells interact during lung formation and repair? How do signaling and transcriptional programs determine cell-cell interactions necessary for lung morphogenesis and function?
Topics: Animals; Cell Differentiation; Cell Proliferation; Embryonic Development; Gene Expression Regulation, Developmental; Humans; Lung; Morphogenesis
PubMed: 30427276
DOI: 10.1152/physrev.00001.2018 -
Seminars in Cell & Developmental Biology Oct 2021The heart is the earliest organ to develop during embryogenesis and is remarkable in its ability to function efficiently as it is being sculpted. Cardiac heart defects... (Review)
Review
The heart is the earliest organ to develop during embryogenesis and is remarkable in its ability to function efficiently as it is being sculpted. Cardiac heart defects account for a high burden of childhood developmental disorders with many remaining poorly understood mechanistically. Decades of work across a multitude of model organisms has informed our understanding of early cardiac differentiation and morphogenesis and has simultaneously opened new and unanswered questions. Here we have synthesized current knowledge in the field and reviewed recent developments in the realm of imaging, bioengineering and genetic technology and ex vivo cardiac modeling that may be deployed to generate more holistic models of early cardiac morphogenesis, and by extension, new platforms to study congenital heart defects.
Topics: Heart; Humans; Models, Biological; Morphogenesis; Pluripotent Stem Cells
PubMed: 33994301
DOI: 10.1016/j.semcdb.2021.04.025 -
Journal of Biomechanics Jan 2023Internal organs such as the heart demonstrate apparent left-right (LR) asymmetric morphology and positioning. Cellular chirality and associated LR biased mechanical...
Internal organs such as the heart demonstrate apparent left-right (LR) asymmetric morphology and positioning. Cellular chirality and associated LR biased mechanical behavior such as cell migration have been attributed to LR symmetry breaking during embryonic development. Mathematical models have shown that chiral directional migration can be driven by cellular intrinsic torque. Tissue jamming state (i.e., solid-like vs fluid-like state) strongly regulates collective migratory behavior, but how it might affect chiral morphogenesis is still unknown. Here, we develop a cell vertex model to study the role of tissue rigidity or jamming state on chiral morphogenesis of the cells on a patterned ring-shaped tissue, simulating a previously reported experimental setup for measuring cell chirality. We simulate chirality as torsional forces acting on cell vertices. As expected, the cells undergo bidirectional migration at the opposing (inner and outer) boundaries of the ring-shaped tissue. We discover that more fluid-like tissues (unjammed) demonstrate a stronger chiral cell alignment and elongation than more solid-like (jammed) tissues and maintain a bigger difference in migration velocity between opposing tissue boundaries. Finally, we find that fluid-like tissues undergo more cell-neighbor exchange events. This study reveals that chiral torque is sufficient to achieve a biased cellular alignment as seen in vitro. It further sheds light on the mechanical regulation of chiral morphogenesis of tissues and reveals a role of cell density-independent tissue rigidity in this process.
Topics: Body Patterning; Morphogenesis; Heart; Cell Movement
PubMed: 36641827
DOI: 10.1016/j.jbiomech.2023.111435