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International Journal of Molecular... Aug 2021To ensure the formation of a properly patterned embryo, multiple processes must operate harmoniously at sequential phases of development. This is implemented by mutual... (Review)
Review
To ensure the formation of a properly patterned embryo, multiple processes must operate harmoniously at sequential phases of development. This is implemented by mutual interactions between cells and tissues that together regulate the segregation and specification of cells, their growth and morphogenesis. The formation of the spinal cord and paraxial mesoderm derivatives exquisitely illustrate these processes. Following early gastrulation, while the vertebrate body elongates, a population of bipotent neuromesodermal progenitors resident in the posterior region of the embryo generate both neural and mesodermal lineages. At later stages, the somitic mesoderm regulates aspects of neural patterning and differentiation of both central and peripheral neural progenitors. Reciprocally, neural precursors influence the paraxial mesoderm to regulate somite-derived myogenesis and additional processes by distinct mechanisms. Central to this crosstalk is the activity of the axial notochord, which, via sonic hedgehog signaling, plays pivotal roles in neural, skeletal muscle and cartilage ontogeny. Here, we discuss the cellular and molecular basis underlying this complex developmental plan, with a focus on the logic of sonic hedgehog activities in the coordination of the neural-mesodermal axis.
Topics: Animals; Cell Differentiation; Embryonic Stem Cells; Gene Expression Regulation, Developmental; Hedgehog Proteins; Humans; Mesoderm; Neural Tube
PubMed: 34502050
DOI: 10.3390/ijms22179141 -
Acta Biochimica Et Biophysica Sinica Jan 2018One of the most important events during vertebrate embryogenesis is the formation or specification of the three germ layers, endoderm, mesoderm, and ectoderm. After a... (Review)
Review
One of the most important events during vertebrate embryogenesis is the formation or specification of the three germ layers, endoderm, mesoderm, and ectoderm. After a series of rapid cleavages, embryos form the mesendoderm and ectoderm during late blastulation and early gastrulation. The mesendoderm then further differentiates into the mesoderm and endoderm. Nodal, a member of the transforming growth factor β (TGF-β) superfamily, plays a pivotal role in mesendoderm formation by regulating the expression of a number of critical transcription factors, including Mix-like, GATA, Sox, and Fox. Because the Nodal signal transduction pathway is well-characterized, increasing effort has been made to delineate the spatiotemporal modulation of Nodal signaling during embryonic development. In this review, we summarize the recent progress delineating molecular regulation of Nodal signal intensity and duration during mesendoderm formation.
Topics: Animals; Ectoderm; Endoderm; Gene Expression Regulation, Developmental; Mesoderm; Mice; Models, Genetic; Nodal Protein; Signal Transduction
PubMed: 29206913
DOI: 10.1093/abbs/gmx128 -
Seminars in Cell & Developmental Biology Aug 2019The pancreas is a compound gland comprised of both exocrine acinar and duct cells as well as endocrine islet cells. Most notable amongst the latter are the... (Review)
Review
The pancreas is a compound gland comprised of both exocrine acinar and duct cells as well as endocrine islet cells. Most notable amongst the latter are the insulin-synthesizing β-cells, loss or dysfunction of which manifests in diabetes mellitus. All exocrine and endocrine cells derive from multipotent pancreatic progenitor cells arising from the primitive gut epithelium via inductive interactions with adjacent mesodermal tissues. Research in the last two decades has revealed the identity of many of these extrinsic cues and they include signaling molecules used in many other developmental contexts such as retinoic acid, fibroblast growth factors, and members of the TGF-β superfamily. As important as these inductive cues is the absence of other signaling molecules such as hedgehog family members. Much has been learned about the interactions of extrinsic factors with fate regulators intrinsic to the pancreatic endoderm. This new knowledge has had tremendous impact on the development of directed differentiation protocols for converting pluripotent stem cells to β-cells in vitro.
Topics: Animals; Humans; Mesoderm; Mice; Pancreas
PubMed: 30142440
DOI: 10.1016/j.semcdb.2018.08.008 -
Seminars in Cell & Developmental Biology Jul 2022A critical stage in the development of all vertebrate embryos is the generation of the body plan and its subsequent patterning and regionalisation along the main... (Review)
Review
A critical stage in the development of all vertebrate embryos is the generation of the body plan and its subsequent patterning and regionalisation along the main anterior-posterior axis. This includes the formation of the vertebral axial skeleton. Its organisation begins during early embryonic development with the periodic formation of paired blocks of mesoderm tissue called somites. Here, we review axial patterning of somites, with a focus on studies using amniote model systems - avian and mouse. We summarise the molecular and cellular mechanisms that generate paraxial mesoderm and review how the different anatomical regions of the vertebral column acquire their specific identity and thus shape the body plan. We also discuss the generation of organoids and embryo-like structures from embryonic stem cells, which provide insights regarding axis formation and promise to be useful for disease modelling.
Topics: Animals; Body Patterning; Embryonic Development; Gene Expression Regulation, Developmental; Mesoderm; Mice; Somites; Spine; Vertebrates
PubMed: 34690064
DOI: 10.1016/j.semcdb.2021.10.003 -
Doklady Biological Sciences :... Dec 2023In Bilateria, the formation of the coelomic mesoderm occurs in various ways and is of great significance for comparative embryology and phylogeny. Several early...
In Bilateria, the formation of the coelomic mesoderm occurs in various ways and is of great significance for comparative embryology and phylogeny. Several early ontogenetic stages were studied in the brachiopod Coptothyris grayi by scanning electron microscopy and cytochemistry combined with confocal laser microscopy. Two sources of the mesoderm were observed to form simultaneously from the anterior and posterior walls of the archenteron at the gastrula stage. Both anterior and posterior rudiments form enterocoely as unpaired protrusions of the wall of the archenteron and are subsequently separated from it. The findings confirmed the previous data on enterocoely in brachiopods. Moreover, a dual origin of the coelomic mesoderm from an anterior and a posterior precursor was for the first time demonstrated for all brachiopods. Analysis of the literature showed that two sources of the coelomic mesoderm in ontogeny are characteristic of representatives of various groups of protostomes and deuterostomes. This fact may provide evidence for the earlier hypothesis of plesiomorphy of two sources of the mesoderm in Bilateria.
Topics: Animals; Invertebrates; Phylogeny; Mesoderm
PubMed: 38190043
DOI: 10.1134/S0012496623700837 -
Current Topics in Developmental Biology 2018The skeletal muscle lineage derives from the embryonic paraxial mesoderm (PM) which also gives rise to the axial skeleton, the dermis of the back, brown fat, meninges,... (Review)
Review
The skeletal muscle lineage derives from the embryonic paraxial mesoderm (PM) which also gives rise to the axial skeleton, the dermis of the back, brown fat, meninges, and endothelial cells. Direct conversion was pioneered in skeletal muscle with overexpression of the transcription factor MyoD which can convert fibroblasts to a muscle fate. In contrast, directed differentiation of skeletal muscle from pluripotent cells (PC) in vitro has proven to be very difficult compared to other lineages and has only been achieved recently. Experimental strategies recapitulating myogenesis in vitro from mouse and human PC (ES/iPS) have now been reported and all rely on early activation of Wnt signaling at the epiblast stage. This leads to induction of neuromesodermal progenitors that can subsequently be induced to a PM fate and to skeletal muscle. These protocols can efficiently produce fetal muscle fibers and immature satellite cells. These new in vitro systems now open the possibility to better understand human myogenesis and to develop in vitro disease models as well as cell therapy approaches.
Topics: Animals; Bone Morphogenetic Proteins; Cell Differentiation; Humans; Mesoderm; Models, Biological; Muscle Development; Stem Cells
PubMed: 29801528
DOI: 10.1016/bs.ctdb.2018.03.003 -
Current Topics in Developmental Biology 2015The perception of our environment via sensory organs plays a crucial role in survival and evolution. Hearing, one of our most developed senses, depends on the proper... (Review)
Review
The perception of our environment via sensory organs plays a crucial role in survival and evolution. Hearing, one of our most developed senses, depends on the proper function of the auditory system and plays a key role in social communication, integration, and learning ability. The ear is a composite structure, comprised of the external, middle, and inner ear. During development, the ear is formed from the integration of a number of tissues of different embryonic origin, which initiate in distinct areas of the embryo at different time points. Functional connections between the components of the hearing apparatus have to be established and maintained during development and adulthood to allow proper sound submission from the outer to the middle and inner ear. This highly organized and intimate connectivity depends on intricate spatiotemporal signaling between the various tissues that give rise to the structures of the ear. Any alterations in this chain of events can lead to the loss of integration, which can subsequently lead to conductive hearing loss, in case of outer and middle ear defects or sensorineural hearing loss, if inner ear structures are defective. This chapter aims to review the current knowledge concerning the development of the three ear compartments as well as mechanisms and signaling pathways that have been implicated in the coordination and integration process of the ear.
Topics: Animals; Ear; Ear, External; Ear, Middle; Epithelium; Hearing; Humans; Mesoderm; Models, Biological; Morphogenesis
PubMed: 26589927
DOI: 10.1016/bs.ctdb.2015.07.007 -
Nature Reviews. Molecular Cell Biology Jul 2024Segmentation is a fundamental feature of the vertebrate body plan. This metameric organization is first implemented by somitogenesis in the early embryo, when paired... (Review)
Review
Segmentation is a fundamental feature of the vertebrate body plan. This metameric organization is first implemented by somitogenesis in the early embryo, when paired epithelial blocks called somites are rhythmically formed to flank the neural tube. Recent advances in in vitro models have offered new opportunities to elucidate the mechanisms that underlie somitogenesis. Notably, models derived from human pluripotent stem cells introduced an efficient proxy for studying this process during human development. In this Review, we summarize the current understanding of somitogenesis gained from both in vivo studies and in vitro studies. We deconstruct the spatiotemporal dynamics of somitogenesis into four distinct modules: dynamic events in the presomitic mesoderm, segmental determination, somite anteroposterior polarity patterning, and epithelial morphogenesis. We first focus on the segmentation clock, as well as signalling and metabolic gradients along the tissue, before discussing the clock and wavefront and other models that account for segmental determination. We then detail the molecular and cellular mechanisms of anteroposterior polarity patterning and somite epithelialization.
Topics: Somites; Animals; Humans; Body Patterning; Vertebrates; Gene Expression Regulation, Developmental; Embryonic Development; Mesoderm; Signal Transduction; Morphogenesis
PubMed: 38418851
DOI: 10.1038/s41580-024-00709-z -
Seminars in Cell & Developmental Biology Aug 2019The liver is an indispensable organ for metabolism and drug detoxification. The liver consists of endoderm-derived hepatobiliary lineages and various mesoderm-derived... (Review)
Review
The liver is an indispensable organ for metabolism and drug detoxification. The liver consists of endoderm-derived hepatobiliary lineages and various mesoderm-derived cells, and interacts with the surrounding tissues and organs through the ventral mesentery. Liver development, from hepatic specification to liver maturation, requires close interactions with mesoderm-derived cells, such as mesothelial cells, hepatic stellate cells, mesenchymal cells, liver sinusoidal endothelial cells and hematopoietic cells. These cells affect liver development through precise signaling events and even direct physical contact. Through the use of new techniques, emerging studies have recently led to a deeper understanding of liver development and its related mechanisms, especially the roles of mesodermal cells in liver development. Based on these developments, the current protocols for in vitro hepatocyte-like cell induction and liver-like tissue construction have been optimized and are of great importance for the treatment of liver diseases. Here, we review the roles of mesoderm-derived cells in the processes of liver development, hepatocyte-like cell induction and liver-like tissue construction.
Topics: Animals; Humans; Liver; Mesoderm; Mice
PubMed: 30193996
DOI: 10.1016/j.semcdb.2018.09.003 -
Current Topics in Developmental Biology 2015The tongue and mandible have common origins. They arise simultaneously from the mandibular arch and are coordinated in their development and growth, which is evident... (Review)
Review
The tongue and mandible have common origins. They arise simultaneously from the mandibular arch and are coordinated in their development and growth, which is evident from several clinical conditions such as Pierre Robin sequence. Here, we review in detail the molecular networks controlling both mandible and tongue development. We also discuss their mechanical relationship and evolution as well as the potential for stem cell-based therapies for disorders affecting these organs.
Topics: Animals; Gene Expression Regulation, Developmental; Humans; Mandible; Mesoderm; Neural Crest; Osteogenesis; Stem Cells; Tendons; Tongue
PubMed: 26589920
DOI: 10.1016/bs.ctdb.2015.07.023