Single cell analysis of mesoderm formation in the Xenopus embryo

Development ◽  
1991 ◽  
Vol 111 (2) ◽  
pp. 523-530 ◽  
Author(s):  
S.F. Godsave ◽  
J.M. Slack

We have examined the developmental specification of individual cells in the Xenopus blastula using a new in vitro culture system. Regional differences are apparent at the mid-blastula stage when animal hemisphere cells form only ectodermal cell types, while many clones from below the pigment boundary contain mesodermal cell types. A number of clones give rise to more than one differentiated cell type indicating that the initial steps of mesoderm induction are potentially reversible. Animal hemisphere cells can be induced to form mesoderm by fibroblast growth factor (FGF). Different cell types predominate at different FGF concentrations and the neighbours in this sequence are also the pairs of cell types most usually associated in mixed clones derived from the marginal zone. We propose that the specification of individual cells depends upon both the concentration of inducing factor and on stochastic intracellular events.

Development ◽  
1992 ◽  
Vol 114 (3) ◽  
pp. 711-720 ◽  
Author(s):  
H.V. Isaacs ◽  
D. Tannahill ◽  
J.M. Slack

We have cloned and sequenced a new member of the fibroblast growth factor family from Xenopus laevis embryo cDNA. It is most closely related to both mammalian kFGF (FGF-4) and FGF-6 but as it is not clear whether it is a true homologue of either of these genes we provisionally refer to it as XeFGF (Xenopus embryonic FGF). Two sequences were obtained, differing by 11% in derived amino acid sequence, which probably represent pseudotetraploid variants. Both the sequence and the behaviour of in vitro translated protein indicates that, unlike bFGF (FGF-2), XeFGF is a secreted molecule. Recombinant XeFGF protein has mesoderm-inducing activity with a specific activity similar to bFGF. XeFGF mRNA is expressed maternally and zygotically with a peak during the gastrula stage. Both probe protection and in situ hybridization showed that the zygotic expression is concentrated in the posterior of the body axis and later in the tailbud. Later domains of expression were found near the midbrain/hindbrain boundary and at low levels in the myotomes. Because of its biological properties and expression pattern, XeFGF is a good candidate for an inducing factor with possible roles both in mesoderm induction at the blastula stage and in the formation of the anteroposterior axis at the gastrula stage.


1993 ◽  
Vol 340 (1293) ◽  
pp. 287-296 ◽  

The mesoderm of amphibian embryos arises through an inductive interaction in which a signal from the vegetal hemisphere of the blastula-stage embryo acts on overlying equatorial cells. Strong candidates for endogenous mesoderm-inducing signals include members of the fibroblast growth factor (FGF) and activin families. In this paper we show that cells form different mesodermal cell types in response to different concentrations of these factors, and that graded distributions of activin and FGF can, in principle, provide sufficient positional information to generate the body plan of the Xenopus embryo.


2020 ◽  
Author(s):  
Brian S. Iskra ◽  
Logan Davis ◽  
Henry E. Miller ◽  
Yu-Chiao Chiu ◽  
Alexander R. Bishop ◽  
...  

AbstractCardiac non-myocytes comprise a diverse and crucial cell population in the heart that plays dynamic roles in cardiac wound healing and growth. Non-myocytes broadly fall into four cell types: endothelium, fibroblasts, leukocytes, and pericytes. Here we characterize the diversity of the non-myocytes in vivo and in vitro using mass cytometry. By leveraging single-cell RNA sequencing we inform the design of a mass cytometry panel. To aid in annotation of the mass cytometry datasets, we utilize data integration with a neural network. We introduce approximately 460,000∼ single cell proteomes of non-myocytes as well as 5,000∼ CD31 negative single cell transcriptomes. Using our data, as well as previously reported datasets, we characterize cardiac non-myocytes with high depth in six mice, characterizing novel surface markers (CD9, CD200, Notch3, and FolR2). Further, we find that extended cell culture promotes the proliferation of CD45+CD11b+FolR2+IAIE- myeloid cells in addition to fibroblasts.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3389
Author(s):  
Ishtiaq Ahmed ◽  
Saif Ur Rehman ◽  
Shiva Shahmohamadnejad ◽  
Muhammad Anjum Zia ◽  
Muhammad Ahmad ◽  
...  

In humans, various sites like cannabinoid receptors (CBR) having a binding affinity with cannabinoids are distributed on the surface of different cell types, where endocannabinoids (ECs) and derivatives of fatty acid can bind. The binding of these substance(s) triggers the activation of specific receptors required for various physiological functions, including pain sensation, memory, and appetite. The ECs and CBR perform multiple functions via the cannabinoid receptor 1 (CB1); cannabinoid receptor 2 (CB2), having a key effect in restraining neurotransmitters and the arrangement of cytokines. The role of cannabinoids in the immune system is illustrated because of their immunosuppressive characteristics. These characteristics include inhibition of leucocyte proliferation, T cells apoptosis, and induction of macrophages along with reduced pro-inflammatory cytokines secretion. The review seeks to discuss the functional relationship between the endocannabinoid system (ECS) and anti-tumor characteristics of cannabinoids in various cancers. The therapeutic potential of cannabinoids for cancer—both in vivo and in vitro clinical trials—has also been highlighted and reported to be effective in mice models in arthritis for the inflammation reduction, neuropathic pain, positive effect in multiple sclerosis and type-1 diabetes mellitus, and found beneficial for treating in various cancers. In human models, such studies are limited; thereby, further research is indispensable in this field to get a conclusive outcome. Therefore, in autoimmune disorders, therapeutic cannabinoids can serve as promising immunosuppressive and anti-fibrotic agents.


2019 ◽  
Vol 2 (1) ◽  
pp. 97-109 ◽  
Author(s):  
Jinchu Vijay ◽  
Marie-Frédérique Gauthier ◽  
Rebecca L. Biswell ◽  
Daniel A. Louiselle ◽  
Jeffrey J. Johnston ◽  
...  

2014 ◽  
Vol 4 (6) ◽  
pp. 20140006 ◽  
Author(s):  
Alexandre Lewalle ◽  
Marco Fritzsche ◽  
Kerry Wilson ◽  
Richard Thorogate ◽  
Tom Duke ◽  
...  

The integration of protein function studied in vitro in a dynamic system like the cell lamellipodium remains a significant challenge. One reason is the apparent contradictory effect that perturbations of some proteins can have on the overall lamellipodium dynamics, depending on exact conditions. Theoretical modelling offers one approach for understanding the balance between the mechanisms that drive and regulate actin network growth and decay. Most models use a ‘bottom-up’ approach, involving explicitly assembling biochemical components to simulate observable behaviour. Their correctness therefore relies on both the accurate characterization of all the components and the completeness of the relevant processes involved. To avoid potential pitfalls due to this uncertainty, we used an alternative ‘top-down’ approach, in which measurable features of lamellipodium behaviour, here observed in two different cell types (HL60 and B16-F1), directly inform the development of a simple phenomenological model of lamellipodium dynamics. We show that the kinetics of F-actin association and dissociation scales with the local F-actin density, with no explicit location dependence. This justifies the use of a simplified kinetic model of lamellipodium dynamics that yields predictions testable by pharmacological or genetic intervention. A length-scale parameter (the lamellipodium width) emerges from this analysis as an experimentally accessible probe of network regulatory processes.


2016 ◽  
Vol 61 (10) ◽  
pp. 1566-1571 ◽  
Author(s):  
A. S. Bukatin ◽  
I. S. Mukhin ◽  
E. I. Malyshev ◽  
I. V. Kukhtevich ◽  
A. A. Evstrapov ◽  
...  

2000 ◽  
Vol 164 (6) ◽  
pp. 3047-3055 ◽  
Author(s):  
Dragana Jankovic ◽  
Marika C. Kullberg ◽  
Nancy Noben-Trauth ◽  
Patricia Caspar ◽  
William E. Paul ◽  
...  

2016 ◽  
Vol 311 (6) ◽  
pp. E952-E963 ◽  
Author(s):  
Yueshui Zhao ◽  
Xue Gu ◽  
Ningyan Zhang ◽  
Mikhail G. Kolonin ◽  
Zhiqiang An ◽  
...  

Endotrophin is a cleavage product of collagen 6 (Col6) in adipose tissue (AT). Previously, we demonstrated that endotrophin serves as a costimulator to trigger fibrosis and inflammation within the unhealthy AT milieu. However, how endotrophin affects lipid storage and breakdown in AT and how different cell types in AT respond to endotrophin stimulation remain unknown. In the current study, by using a doxycycline-inducible mouse model, we observed significant upregulation of adipogenic genes in the white AT (WAT) of endotrophin transgenic mice. We further showed that the mice exhibited inhibited lipolysis and accelerated hypertrophy and hyperplasia in WAT. To investigate the effects of endotrophin in vitro, we incubated different cell types from AT with conditioned medium from endotrophin-overexpressing 293T cells. We found that endotrophin activated multiple pathological pathways in different cell types. Particularly in 3T3-L1 adipocytes, endotrophin triggered a fibrotic program by upregulating collagen genes and promoted abnormal lipid accumulation by downregulating hormone-sensitive lipolysis gene and decreasing HSL phosphorylation levels. In macrophages isolated from WAT, endotrophin stimulated higher expression of the collagen-linking enzyme lysyl oxidase and M1 proinflammatory marker genes. In the stromal vascular fraction isolated from WAT, endotrophin induced upregulation of both profibrotic and proinflammatory genes. In conclusion, our study provides a new perspective on the effect of endotrophin in abnormal lipid accumulation and a mechanistic insight into the roles played by adipocytes and a variety of other cell types in AT in shaping the unhealthy microenvironment upon endotrophin treatment.


Sign in / Sign up

Export Citation Format

Share Document