Diversity of Nuclear Lamin A/C Action as a Key to Tissue-Specific Regulation of Cellular Identity in Health and Disease

A-type lamins are the main structural components of the nucleus, which are mainly localized at the nucleus periphery. First of all, A-type lamins, together with B-type lamins and proteins of the inner nuclear membrane, form a stiff structure—the nuclear lamina. Besides maintaining the nucleus cell shape, A-type lamins play a critical role in many cellular events, such as gene transcription and epigenetic regulation. Nowadays it is clear that lamins play a very important role in determining cell fate decisions. Various mutations in genes encoding A-type lamins lead to damages of different types of tissues in humans, collectively known as laminopathies, and it is clear that A-type lamins are involved in the regulation of cell differentiation and stemness. However, the mechanisms of this regulation remain unclear. In this review, we discuss how A-type lamins can execute their regulatory role in determining the differentiation status of a cell. We have summarized recent data focused on lamin A/C action mechanisms in regulation of cell differentiation and identity development of stem cells of different origin. We also discuss how this knowledge can promote further research toward a deeper understanding of the role of lamin A/C mutations in laminopathies.

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Ultra-multiplexed analysis of single-cell dynamics reveals logic rules in differentiation

Science Advances ◽

10.1126/sciadv.aav7959 ◽

2019 ◽

Vol 5 (4) ◽

pp. eaav7959 ◽

Cited By ~ 19

Author(s):

Ce Zhang ◽

Hsiung-Lin Tu ◽

Gengjie Jia ◽

Tanzila Mukhtar ◽

Verdon Taylor ◽

...

Keyword(s):

Stem Cell ◽

Cell Differentiation ◽

Single Cell ◽

Cell Fate ◽

Single Cell Analysis ◽

Single Cells ◽

Critical Role ◽

Stem Cell Differentiation ◽

Cell Fate Decisions ◽

Cellular Microenvironments

Dynamical control of cellular microenvironments is highly desirable to study complex processes such as stem cell differentiation and immune signaling. We present an ultra-multiplexed microfluidic system for high-throughput single-cell analysis in precisely defined dynamic signaling environments. Our system delivers combinatorial and time-varying signals to 1500 independently programmable culture chambers in week-long live-cell experiments by performing nearly 106 pipetting steps, where single cells, two-dimensional (2D) populations, or 3D neurospheres are chemically stimulated and tracked. Using our system and statistical analysis, we investigated the signaling landscape of neural stem cell differentiation and discovered “cellular logic rules” that revealed the critical role of signal timing and sequence in cell fate decisions. We find synergistic and antagonistic signal interactions and show that differentiation pathways are highly redundant. Our system allows dissection of hidden aspects of cellular dynamics and enables accelerated biological discovery.

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The LINC complex transmits integrin-dependent tension to the nuclear lamina and represses epidermal differentiation

10.1101/2020.05.03.075085 ◽

2020 ◽

Cited By ~ 1

Author(s):

Emma Carley ◽

Rachel K. Stewart ◽

Abigail Zieman ◽

Iman Jalilian ◽

Diane. E. King ◽

...

Keyword(s):

Cell Fate ◽

Control Cell ◽

Nuclear Lamina ◽

Epidermal Differentiation ◽

Keratinocyte Differentiation ◽

Linc Complex ◽

Force Transmission ◽

Cell Fate Decisions

AbstractWhile the mechanisms by which chemical signals control cell fate have been well studied, how mechanical inputs impact cell fate decisions are not well understood. Here, using the well-defined system of keratinocyte differentiation in the skin, we examine whether and how direct force transmission to the nucleus regulates epidermal cell fate. Using a molecular biosensor, we find that tension on the nucleus through Linker of Nucleoskeleton and Cytoskeleton (LINC) complexes requires integrin engagement in undifferentiated epidermal stem cells, and is released during differentiation concomitant with decreased tension on A-type lamins. LINC complex ablation in mice reveals that LINC complexes are required to repress epidermal differentiation in vivo and in vitro and influence accessibility of epidermal differentiation genes, suggesting that force transduction from engaged integrins to the nucleus plays a role in maintaining keratinocyte progenitors. This work reveals a direct mechanotransduction pathway capable of relaying adhesion-specific signals to regulate cell fate.

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Uncovering the mesendoderm gene regulatory network through multi-omic data integration

10.1101/2020.11.01.362053 ◽

2020 ◽

Author(s):

Camden Jansen ◽

Kitt D. Paraiso ◽

Jeff J. Zhou ◽

Ira L. Blitz ◽

Margaret B. Fish ◽

...

Keyword(s):

Cell Differentiation ◽

Cell Fate ◽

Data Sets ◽

List Type ◽

Rna Seq ◽

Data Types ◽

Cell Fate Decisions ◽

Gene Regulatory ◽

Genome Scale ◽

Omic Data

SummaryMesendodermal specification is one of the earliest events in embryogenesis, where cells first acquire distinct identities. Cell differentiation is a highly regulated process that involves the function of numerous transcription factors (TFs) and signaling molecules, which can be described with gene regulatory networks (GRNs). Cell differentiation GRNs are difficult to build because existing mechanistic methods are low-throughput, and high-throughput methods tend to be non-mechanistic. Additionally, integrating highly dimensional data comprised of more than two data types is challenging. Here, we use linked self-organizing maps to combine ChIP-seq/ATAC-seq with temporal, spatial and perturbation RNA-seq data from Xenopus tropicalis mesendoderm development to build a high resolution genome scale mechanistic GRN. We recovered both known and previously unsuspected TF-DNA/TF-TF interactions and validated through reporter assays. Our analysis provides new insights into transcriptional regulation of early cell fate decisions and provides a general approach to building GRNs using highly-dimensional multi-omic data sets.HighlightsBuilt a generally applicable pipeline to creating GRNs using highly-dimensional multi-omic data setsPredicted new TF-DNA/TF-TF interactions during mesendoderm developmentGenerate the first genome scale GRN for vertebrate mesendoderm and expanded the core mesendodermal developmental network with high fidelityDeveloped a resource to visualize hundreds of RNA-seq and ChIP-seq data using 2D SOM metaclusters.

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A novel Axin2 knock-in mouse model for visualization and lineage tracing of WNT/CTNNB1 responsive cells

10.1101/2020.04.03.024182 ◽

2020 ◽

Cited By ~ 1

Author(s):

Anoeska Agatha Alida van de Moosdijk ◽

Yorick Bernardus Cornelis van de Grift ◽

Saskia Madelon Ada de Man ◽

Amber Lisanne Zeeman ◽

Renée van Amerongen

Keyword(s):

Cell Fate ◽

Mouse Strain ◽

Critical Role ◽

Lineage Tracing ◽

Fluorescent Reporter ◽

Cell Fate Decisions ◽

Stem Cell Maintenance ◽

Signaling Dynamics ◽

Before And After

AbstractWnt signal transduction controls tissue morphogenesis, maintenance and regeneration in all multicellular animals. In mammals, the WNT/CTNNB1 (Wnt/β-catenin) pathway controls cell proliferation and cell fate decisions before and after birth. It plays a critical role at multiple stages of embryonic development, but also governs stem cell maintenance and homeostasis in adult tissues. However, it remains challenging to monitor endogenous WNT/CTNNB1 signaling dynamics in vivo. Here we report the generation and characterization of a new knock-in mouse strain that doubles as a fluorescent reporter and lineage tracing driver for WNT/CTNNB1 responsive cells. We introduced a multi-cistronic targeting cassette at the 3’ end of the universal WNT/CTNNB1 target gene Axin2. The resulting knock-in allele expresses a bright fluorescent reporter (3xNLS-SGFP2) and a doxycycline-inducible driver for lineage tracing (rtTA3). We show that the Axin2P2A-rtTA3-T2A-3xNLS-SGFP2 strain labels WNT/CTNNB1 cells at multiple anatomical sites during different stages of embryonic and postnatal development. It faithfully reports the subtle and dynamic changes in physiological WNT/CTNNB1 signaling activity that occur in vivo. We expect this mouse strain to be a useful resource for biologists who want to track and trace the location and developmental fate of WNT/CTNNB1 responsive stem cells in different contexts.Abstract Figure

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Requirement of Activation of JNK and p38 for Environmental Stress-Induced Erythroid Differentiation and Apoptosis and of Inhibition of ERK for Apoptosis

Blood ◽

10.1182/blood.v94.3.853.415a12_853_863 ◽

1999 ◽

Vol 94 (3) ◽

pp. 853-863 ◽

Cited By ~ 160

Author(s):

Yuka Nagata ◽

Kazuo Todokoro

Keyword(s):

Cell Differentiation ◽

Protein Kinases ◽

Cell Fate ◽

Critical Role ◽

Erythroid Differentiation ◽

Short Exposure ◽

Amino Terminal ◽

Transient Activation ◽

Apoptosis Inhibition ◽

Induced Apoptosis

C-Jun amino terminal kinase/stress-activated protein kinases (JNK/SAPK) and p38 subgroups of mitogen-activated protein kinases have been suggested to play a critical role in apoptosis, cell growth, and/or differentiation. We found that a short exposure of SKT6 cells, which respond to erythropoietin (Epo) and induce erythroid differentiation, to osmotic or heat shock induced transient activation of JNK/SAPK and p38 and inactivation of ERK and resulted in erythroid differentiation without Epo, whereas long exposure of the cells to these stresses induced prolonged activation/inactivation of the same kinases and caused apoptosis. Inhibition of JNK/SAPK and p38 resulted in inhibition of stress-induced erythroid differentiation and apoptosis. Inhibition of ERK had no effect on stress-induced erythroid differentiation, but stimulated apoptosis. Activation of p38 and/or JNK/SAPK for a short time caused erythroid differentiation without Epo, although its prolonged activation induced apoptosis. Activation of ERK suppressed stress-induced apoptosis. These results indicate that short cellular stresses, inducing transient activation of JNK/SAPK and p38, lead to cell differentiation rather than apoptosis. Furthermore, activation of JNK/SAPK and p38 is required for both cell differentiation and apoptosis, and the duration of their activation may determine the cell fate, cell differentiation, and apoptosis. In contrast, inactivation of ERK is required for stress-induced apoptosis but not cell differentiation.

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MTG16 (CBFA2T3) represses E protein-dependent transcription to regulate colonic secretory cell differentiation, epithelial regeneration, and tumorigenesis

10.1101/2021.11.03.467178 ◽

2021 ◽

Author(s):

Rachel E. Brown ◽

Justin Jacobse ◽

Shruti A. Anant ◽

Koral M. Blunt ◽

Bob Chen ◽

...

Keyword(s):

Cell Differentiation ◽

Mouse Model ◽

Cell Fate ◽

Protein Interactions ◽

Protein Function ◽

Colonic Epithelium ◽

E Proteins ◽

Cell Fate Decisions ◽

Epithelial Regeneration ◽

E Protein

Aberrant epithelial differentiation and regeneration pathways contribute to colon pathologies including inflammatory bowel disease (IBD) and colitis-associated cancer (CAC). MTG16 (also known as CBFA2T3) is a transcriptional corepressor expressed in the colonic epithelium. MTG16 interaction partners include E box-binding basic helix-loop-helix transcription factors (E proteins). MTG16-deficient mice exhibit worse colitis and increased tumor burden in inflammatory carcinogenesis. In this study, we sought to understand the role of MTG16 in colonic epithelial homeostasis and the mechanisms by which MTG16 protects the epithelium in colitis and CAC. We demonstrated that MTG16 deficiency enabled enteroendocrine cell differentiation from secretory precursor cells at the expense of goblet cells. Transcriptomic analysis implicated dysregulated E protein function in MTG16-deficient colon crypts. Using a novel mouse model with a point mutation that disrupts MTG16:E protein complex formation (Mtg16P209T), we established that enteroendocrine:goblet cell balance was dependent on MTG16:E protein interactions and that the shift in lineage allocation was associated with enhanced expression of Neurog3, the central driver of enteroendocrine lineage specification. Furthermore, Mtg16 was upregulated in the previously described Ascl2+, de-differentiating cells that replenish the stem cell compartment in response to colon injury. Mtg16 expression was also increased in dextran sulfate sodium (DSS)-treated mouse colon crypts and in IBD patients compared to unaffected controls. We determined that the effects of MTG16 in regeneration are also dependent on its repression of E proteins, as the colonic epithelium failed to regenerate following DSS-induced injury in our novel mutant mouse model. Finally, we revealed that uncoupling MTG16:E protein interactions contributes to the enhanced tumorigenicity in Mtg16-/- colon in the azoxymethane(AOM)/DSS-induced model of CAC. Collectively, our results demonstrate that MTG16, via its repression of E protein targets, is a key regulator of cell fate decisions during colonic differentiation and regeneration.

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Laminin β2 Chain Regulates Cell Cycle Dynamics in the Developing Retina

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.802593 ◽

2022 ◽

Vol 9 ◽

Author(s):

Dmitri Serjanov ◽

Galina Bachay ◽

Dale D. Hunter ◽

William J. Brunken

Keyword(s):

Cell Cycle ◽

Cell Fate ◽

Critical Role ◽

Laminin Receptor ◽

Cell Cycle Exit ◽

Cell Fate Decisions ◽

M Phase ◽

Cell Cycle Dynamics ◽

Laminin Β2

Vertebrate retinal development follows a highly stereotyped pattern, in which the retinal progenitor cells (RPCs) give rise to all retinal types in a conserved temporal sequence. Ensuring the proper control over RPC cell cycle exit and re-entry is, therefore, crucially important for the generation of properly functioning retina. In this study, we demonstrate that laminins, indispensible ECM components, at the retinal surface, regulate the mechanisms determining whether RPCs generate proliferative or post-mitotic progeny. In vivo deletion of laminin β2 in mice resulted in disturbing the RPC cell cycle dynamics, and premature cell cycle exit. Specifically, the RPC S-phase is shortened, with increased numbers of cells present in its late stages. This is followed by an accelerated G2-phase, leading to faster M-phase entry. Finally, the M-phase is extended, with RPCs dwelling longer in prophase. Addition of exogenous β2-containing laminins to laminin β2-deficient retinal explants restored the appropriate RPC cell cycle dynamics, as well as S and M-phase progression, leading to proper cell cycle re-entry. Moreover, we show that disruption of dystroglycan, a laminin receptor, phenocopies the laminin β2 deletion cell cycle phenotype. Together, our findings suggest that dystroglycan-mediated ECM signaling plays a critical role in regulating the RPC cell cycle dynamics, and the ensuing cell fate decisions.

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Notch Coordinates Periodontal Ligament Maturation through Regulating Lamin A

Journal of Dental Research ◽

10.1177/0022034519871448 ◽

2019 ◽

Vol 98 (12) ◽

pp. 1357-1366 ◽

Cited By ~ 2

Author(s):

B.J. Denes ◽

C. Bolton ◽

C.S. Illsley ◽

W.L. Kok ◽

J.V. Walker ◽

...

Keyword(s):

Cell Fate ◽

Periodontal Ligament ◽

Periodontal Diseases ◽

Notch Pathway ◽

Nuclear Lamina ◽

Tooth Eruption ◽

Conditional Knockout ◽

Molecular Networks ◽

Lamin A ◽

Major Player

Tooth eruption is a continuous biological process with dynamic changes at cellular and tissue levels, particularly within the periodontal ligament (PDL). Occlusion completion is a significant physiological landmark of dentition establishment. However, the importance of the involvement of molecular networks engaging in occlusion establishment on the final PDL maturation is still largely unknown. In this study, using rat and mouse molar teeth and a human PDL cell line for RNAseq and proteomic analysis, we systematically screened the key molecular links in regulating PDL maturation before and after occlusion establishment. We discovered Notch, a key molecular pathway in regulating stem cell fate and differentiation, is a major player in the event. Intercepting the Notch pathway by deleting its key canonical transcriptional factor, RBP-Jkappa, using a conditional knockout strategy in the mice delayed PDL maturation. We also identified that Lamin A, a cell nuclear lamina member, is a unique marker of PDL maturation, and its expression is under the control of Notch signaling. Our study therefore provides a deep insight of how PDL maturation is regulated at the molecular level, and we expect the outcomes to be applied for a better understanding of the molecular regulation networks in physiological conditions such as tooth eruption and movement and also for periodontal diseases.

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Concentric organization of A- and B-type lamins predicts their distinct roles in the spatial organization and stability of the nuclear lamina

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1810070116 ◽

2019 ◽

Vol 116 (10) ◽

pp. 4307-4315 ◽

Cited By ~ 17

Author(s):

Bruce Nmezi ◽

Jianquan Xu ◽

Rao Fu ◽

Travis J. Armiger ◽

Guillermo Rodriguez-Bey ◽

...

Keyword(s):

Spatial Organization ◽

Critical Role ◽

Nuclear Lamina ◽

Nuclear Shape ◽

Lamin A ◽

Concentric Ring ◽

Lamin B1 ◽

Functional Consequences ◽

Optical Reconstruction ◽

Interacting Networks

The nuclear lamina is an intermediate filament meshwork adjacent to the inner nuclear membrane (INM) that plays a critical role in maintaining nuclear shape and regulating gene expression through chromatin interactions. Studies have demonstrated that A- and B-type lamins, the filamentous proteins that make up the nuclear lamina, form independent but interacting networks. However, whether these lamin subtypes exhibit a distinct spatial organization or whether their organization has any functional consequences is unknown. Using stochastic optical reconstruction microscopy (STORM) our studies reveal that lamin B1 and lamin A/C form concentric but overlapping networks, with lamin B1 forming the outer concentric ring located adjacent to the INM. The more peripheral localization of lamin B1 is mediated by its carboxyl-terminal farnesyl group. Lamin B1 localization is also curvature- and strain-dependent, while the localization of lamin A/C is not. We also show that lamin B1’s outer-facing localization stabilizes nuclear shape by restraining outward protrusions of the lamin A/C network. These two findings, that lamin B1 forms an outer concentric ring and that its localization is energy-dependent, are significant as they suggest a distinct model for the nuclear lamina—one that is able to predict its behavior and clarifies the distinct roles of individual nuclear lamin proteins and the consequences of their perturbation.

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Constitutively active Notch4 promotes early human hematopoietic progenitor cell maintenance while inhibiting differentiation and causes lymphoid abnormalities in vivo

Blood ◽

10.1182/blood-2004-01-0204 ◽

2004 ◽

Vol 104 (8) ◽

pp. 2315-2322 ◽

Cited By ~ 47

Author(s):

Suzanne M. Vercauteren ◽

Heather J. Sutherland

Keyword(s):

Stem Cells ◽

T Cell ◽

Cell Fate ◽

Fluorescent Protein ◽

Critical Role ◽

Cell Activity ◽

Hematopoietic Progenitor Cell ◽

Hematopoietic Stem ◽

Cell Fate Decisions ◽

Constitutively Active

Abstract Notch transmembrane receptors are known to play a critical role in cell-fate decisions, with Notch1 shown to enhance self-renewal of hematopoietic stem cells and cause T-cell leukemia. Four Notch receptors exist, and the extent of redundancy and overlap in their function is unknown. Notch4 is structurally distinct from Notch1 through Notch3 and has not been extensively studied in hematopoiesis. By polymerase chain reaction (PCR) we find Notch4 transcript expression in human marrow cells and in both CD34+ and CD34– populations. When constitutively active Notch1 or Notch4 was overexpressed in normal human marrow or cord cells, we found reduced colony-forming and short-term proliferative ability while the primitive progenitor content of myeloid long-term cultures was significantly increased. Notch4–intracellular domain (Notch4-IC)–transduced cord cells transplanted into β2-microglobulin–/– nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice resulted in significantly higher levels of engraftment of both green fluorescent protein–positive (GFP+) and GFP– populations as compared with controls. GFP+ cells in bone marrow and spleen of animals that had received transplants gave rise to an immature CD4+CD8+ T-cell population, whereas B-cell development was blocked. These results indicate that activation of Notch4 results in enhanced stem cell activity, reduced differentiation, and altered lymphoid development, suggesting it may influence both stem cells and the fate of the common lymphoid progenitor.

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