Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
1.
EMBO J ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997504

RESUMEN

Cell communication coordinates developmental processes, maintains homeostasis, and contributes to disease. Therefore, understanding the relationship between cells in a shared environment is crucial. Here we introduce Positive Ultra-bright Fluorescent Fusion For Identifying Neighbours (PUFFFIN), a cell neighbour-labelling system based upon secretion and uptake of positively supercharged fluorescent protein s36GFP. We fused s36GFP to mNeonGreen or to a HaloTag, facilitating ultra-bright, sensitive, colour-of-choice labelling. Secretor cells transfer PUFFFIN to neighbours while retaining nuclear mCherry, making identification, isolation, and investigation of live neighbours straightforward. PUFFFIN can be delivered to cells, tissues, or embryos on a customisable single-plasmid construct composed of interchangeable components with the option to incorporate any transgene. This versatility enables the manipulation of cell properties, while simultaneously labelling surrounding cells, in cell culture or in vivo. We use PUFFFIN to ask whether pluripotent cells adjust the pace of differentiation to synchronise with their neighbours during exit from naïve pluripotency. PUFFFIN offers a simple, sensitive, customisable approach to profile non-cell-autonomous responses to natural or induced changes in cell identity or behaviour.

2.
Development ; 151(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38165174

RESUMEN

Cell-cell interactions are central to development, but exploring how a change in any given cell relates to changes in the neighbour of that cell can be technically challenging. Here, we review recent developments in synthetic biology and image analysis that are helping overcome this problem. We highlight the opportunities presented by these advances and discuss opportunities and limitations in applying them to developmental model systems.


Asunto(s)
Comunicación Celular , Biología Sintética
3.
Development ; 149(12)2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35616331

RESUMEN

Cell-cell interactions govern differentiation and cell competition in pluripotent cells during early development, but the investigation of such processes is hindered by a lack of efficient analysis tools. Here, we introduce SyNPL: clonal pluripotent stem cell lines that employ optimised Synthetic Notch (SynNotch) technology to report cell-cell interactions between engineered 'sender' and 'receiver' cells in cultured pluripotent cells and chimaeric mouse embryos. A modular design makes it straightforward to adapt the system for programming differentiation decisions non-cell-autonomously in receiver cells in response to direct contact with sender cells. We demonstrate the utility of this system by enforcing neuronal differentiation at the boundary between two cell populations. In summary, we provide a new adaptation of SynNotch technology that could be used to identify cell interactions and to profile changes in gene or protein expression that result from direct cell-cell contact with defined cell populations in culture and in early embryos, and that can be customised to generate synthetic patterning of cell fate decisions.


Asunto(s)
Células Madre Pluripotentes , Animales , Comunicación Celular , Diferenciación Celular/genética , Línea Celular , Células Cultivadas , Ratones
4.
Development ; 147(12)2020 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-32487737

RESUMEN

The intrinsic mechanisms that link extracellular signalling to the onset of neural differentiation are not well understood. In pluripotent mouse cells, BMP blocks entry into the neural lineage via transcriptional upregulation of inhibitor of differentiation (Id) factors. We have previously identified the major binding partner of Id proteins in pluripotent cells as the basic helix-loop-helix (bHLH) transcription factor (TF) E2A. Id1 can prevent E2A from forming heterodimers with bHLH TFs or from forming homodimers. Here, we show that overexpression of a forced E2A homodimer is sufficient to drive robust neural commitment in pluripotent cells, even under non-permissive conditions. Conversely, we find that E2A null cells display a defect in their neural differentiation capacity. E2A acts as an upstream activator of neural lineage genes, including Sox1 and Foxd4, and as a repressor of Nodal signalling. Our results suggest a crucial role for E2A in establishing neural lineage commitment in pluripotent cells.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular , Neuronas/metabolismo , Regiones no Traducidas 3' , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/deficiencia , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Sistemas CRISPR-Cas/genética , Linaje de la Célula , Autorrenovación de las Células , Dimerización , Ratones , Células Madre Embrionarias de Ratones/citología , Células Madre Embrionarias de Ratones/metabolismo , Neuronas/citología , Factor 3 de Transcripción de Unión a Octámeros/deficiencia , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , ARN Guía de Kinetoplastida/metabolismo , Factores de Transcripción SOXB1/deficiencia , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Transcriptoma , Regulación hacia Arriba
5.
Development ; 146(21)2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31601548

RESUMEN

A switch from E- to N-cadherin regulates the transition from pluripotency to neural identity, but the mechanism by which cadherins regulate differentiation was previously unknown. Here, we show that the acquisition of N-cadherin stabilises neural identity by dampening anti-neural signals. We use quantitative image analysis to show that N-cadherin promotes neural differentiation independently of its effects on cell cohesiveness. We reveal that cadherin switching diminishes the level of nuclear ß-catenin, and that N-cadherin also dampens FGF activity and consequently stabilises neural fate. Finally, we compare the timing of cadherin switching and differentiation in vivo and in vitro, and find that this process becomes dysregulated during in vitro differentiation. We propose that N-cadherin helps to propagate a stable neural identity throughout the emerging neuroepithelium, and that dysregulation of this process contributes to asynchronous differentiation in culture.


Asunto(s)
Cadherinas/fisiología , Células Madre Embrionarias/citología , Neuronas/citología , beta Catenina/fisiología , Animales , Diferenciación Celular , Linaje de la Célula , Núcleo Celular/fisiología , Células Cultivadas , Factores de Crecimiento de Fibroblastos/fisiología , Estratos Germinativos/fisiología , Ratones , Ratones Transgénicos , Células Madre Pluripotentes/citología
6.
Cell Mol Life Sci ; 78(9): 4435-4450, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33796894

RESUMEN

During early neural development, changes in signalling inform the expression of transcription factors that in turn instruct changes in cell identity. At the same time, switches in adhesion molecule expression result in cellular rearrangements that define the morphology of the emerging neural tube. It is becoming increasingly clear that these two processes influence each other; adhesion molecules do not simply operate downstream of or in parallel with changes in cell identity but rather actively feed into cell fate decisions. Why are differentiation and adhesion so tightly linked? It is now over 60 years since Conrad Waddington noted the remarkable "Constancy of the Wild Type" (Waddington in Nature 183: 1654-1655, 1959) yet we still do not fully understand the mechanisms that make development so reproducible. Conversely, we do not understand why directed differentiation of cells in a dish is sometimes unpredictable and difficult to control. It has long been suggested that cells make decisions as 'local cooperatives' rather than as individuals (Gurdon in Nature 336: 772-774, 1988; Lander in Cell 144: 955-969, 2011). Given that the cadherin family of adhesion molecules can simultaneously influence morphogenesis and signalling, it is tempting to speculate that they may help coordinate cell fate decisions between neighbouring cells in the embryo to ensure fidelity of patterning, and that the uncoupling of these processes in a culture dish might underlie some of the problems with controlling cell fate decisions ex-vivo. Here we review the expression and function of cadherins during early neural development and discuss how and why they might modulate signalling and differentiation as neural tissues are formed.


Asunto(s)
Cadherinas/metabolismo , Cresta Neural/metabolismo , Animales , Cadherinas/química , Cadherinas/clasificación , Adhesión Celular , Diferenciación Celular , Evolución Molecular , Humanos , Cresta Neural/citología , Cresta Neural/crecimiento & desarrollo , Neurogénesis , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
7.
Stem Cells ; 31(8): 1511-22, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23649667

RESUMEN

Robust development of the early embryo may benefit from mechanisms that ensure that not all pluripotent cells differentiate at exactly the same time: such mechanisms would build flexibility into the process of lineage allocation. This idea is supported by the observation that pluripotent stem cells differentiate at different rates in vitro. We use a clonal commitment assay to confirm that pluripotent cells commit to differentiate asynchronously even under uniform differentiation conditions. Stochastic variability in expression of the Notch target gene Hes1 has previously been reported to influence neural versus mesodermal differentiation through modulation of Notch activity. Here we report that Hes1 also has an earlier role to delay exit from the pluripotent state into all lineages. The early function of Hes1 to delay differentiation can be explained by an ability of Hes1 to amplify STAT3 responsiveness in a cell-autonomous manner. Variability in Hes1 expression therefore helps to explain why STAT3 responsiveness varies between individual ES cells, and this in turn helps to explain why pluripotent cells commit to differentiate asynchronously.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proteínas de Homeodominio/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Receptores Notch/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Diferenciación Celular/fisiología , Regulación hacia Abajo , Humanos , Ratones , Proteína Homeótica Nanog , Transducción de Señal , Factor de Transcripción HES-1 , Transfección
8.
Front Cell Dev Biol ; 10: 1016367, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36420143

RESUMEN

Although the lineage-determining ability of transcription factors is often modulated according to cellular context, the mechanisms by which such switching occurs are not well known. Using a transcriptional programming model, we found that Atoh1 is repurposed from a neuronal to an inner ear hair cell (HC) determinant by the combined activities of Gfi1 and Pou4f3. In this process, Atoh1 maintains its regulation of neuronal genes but gains ability to regulate HC genes. Pou4f3 enables Atoh1 access to genomic locations controlling the expression of sensory (including HC) genes, but Atoh1 + Pou4f3 are not sufficient for HC differentiation. Gfi1 is key to the Atoh1-induced lineage switch, but surprisingly does not alter Atoh1's binding profile. Gfi1 acts in two divergent ways. It represses the induction by Atoh1 of genes that antagonise HC differentiation, a function in keeping with its well-known repressor role in haematopoiesis. Remarkably, we find that Gfi1 also acts as a co-activator: it binds directly to Atoh1 at existing target genes to enhance its activity. These findings highlight the diversity of mechanisms by which one TF can redirect the activity of another to enable combinatorial control of cell identity.

9.
Dev Cell ; 50(4): 462-477.e5, 2019 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-31204172

RESUMEN

Controlling responsiveness to prevailing signals is critical for robust transitions between cell states during development. For example, fibroblast growth factor (FGF) drives naive pluripotent cells into extraembryonic lineages before implantation but sustains pluripotency in primed cells of the post-implantation epiblast. Nanog supports pluripotency in naive cells, while Nodal supports pluripotency in primed cells, but the handover from Nanog to Nodal does not proceed seamlessly, opening up the risk of aberrant differentiation if FGF is activated before Nodal. Here, we report that Id1 acts as a sensor to detect delays in Nodal activation after the downregulation of Nanog. Id1 then suppresses FGF activity to delay differentiation. Accordingly, Id1 is not required for naive or primed pluripotency but rather stabilizes epiblast identity during the transition between these states. These findings help explain how development proceeds robustly in the face of imprecise signals and highlight the importance of mechanisms that stabilize cell identity during developmental transitions.


Asunto(s)
Desarrollo Embrionario/genética , Proteína 1 Inhibidora de la Diferenciación/genética , Proteína Homeótica Nanog/genética , Proteína Nodal/genética , Animales , Diferenciación Celular/genética , Linaje de la Célula/genética , Embrión de Mamíferos/metabolismo , Células Madre Embrionarias/metabolismo , Factores de Crecimiento de Fibroblastos/genética , Regulación del Desarrollo de la Expresión Génica/genética , Estratos Germinativos/crecimiento & desarrollo , Estratos Germinativos/metabolismo , Humanos , Ratones , Células Madre Pluripotentes/metabolismo , Transducción de Señal/genética
10.
Elife ; 2: e01197, 2013 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-24347544

RESUMEN

Bone morphogenic protein (BMP) signalling contributes towards maintenance of pluripotency and favours mesodermal over neural fates upon differentiation, but the mechanisms by which BMP controls differentiation are not well understood. We report that BMP regulates differentiation by blocking downregulation of Cdh1, an event that accompanies the earliest stages of neural and mesodermal differentiation. We find that loss of Cdh1 is a limiting requirement for differentiation of pluripotent cells, and that experimental suppression of Cdh1 activity rescues the BMP-imposed block to differentiation. We further show that BMP acts prior to and independently of Cdh1 to prime pluripotent cells for mesoderm differentiation, thus helping to reinforce the block to neural differentiation. We conclude that differentiation depends not only on exposure to appropriate extrinsic cues but also on morphogenetic events that control receptivity to those differentiation cues, and we explain how a key pluripotency signal, BMP, feeds into this control mechanism. DOI: http://dx.doi.org/10.7554/eLife.01197.001.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Cadherinas/metabolismo , Diferenciación Celular , Transducción de Señal , Humanos , Proteína 1 Inhibidora de la Diferenciación/genética , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA