Expression of the adaptor protein m-Numb in mouse male germ cells

Numb is an adaptor protein that is asymmetrically inherited at mitosis and controls the fate of sibling cells in different species. The role of m-Numb (mammalian Numb) as an important cell fate-determining factor has extensively been described mostly in neural tissues, particularly in progenitor cells, in the mouse. Biochemical and genetic analyses have shown that Numb acts as an inhibitor of the Notch signaling pathway, an evolutionarily conserved pathway involved in the control of cell proliferation, differentiation, and apoptosis. In the present study, we sought to determine m-Numb distribution in germ cells in the postnatal mouse testis. We show that all four m-Numb isoforms are widely expressed during postnatal testis development. By reverse transcriptase-PCR and western blot analyses, we further identify p71 as the predominantly expressed isoform in germ cells. Moreover, we demonstrate through co-immunoprecipitation studies that m-Numb physically associates with Ap2a1, a component of the endocytotic clathrin-coated vesicles. Finally, we employed confocal immunofluorescence microscopy of whole mount seminiferous tubules and isolated germ cells to gain more insight into the subcellular localization of m-Numb. These morphological analyses confirmed m-Numb and Ap2a1 co-localization. However, we did not observe asymmetric localization of m-Numb neither in mitotic spermatogonial stem cells nor in more differentiated spermatogonial cells, suggesting that spermatogonial stem cell fate in the mouse does not rely on asymmetric partitioning of m-Numb.

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Increasing Notch signaling antagonizes PRC2-mediated silencing to promote reprograming of germ cells into neurons

eLife ◽

10.7554/elife.15477 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 21

Author(s):

Stefanie Seelk ◽

Irene Adrian-Kalchhauser ◽

Balázs Hargitai ◽

Martina Hajduskova ◽

Silvia Gutnik ◽

...

Keyword(s):

Notch Signaling ◽

Cell Fate ◽

Germ Cells ◽

Molecular Mechanisms ◽

Notch Signaling Pathway ◽

Germline Stem Cells ◽

Polycomb Repressive Complex 2 ◽

C Elegans ◽

Functional Studies

Cell-fate reprograming is at the heart of development, yet very little is known about the molecular mechanisms promoting or inhibiting reprograming in intact organisms. In the C. elegans germline, reprograming germ cells into somatic cells requires chromatin perturbation. Here, we describe that such reprograming is facilitated by GLP-1/Notch signaling pathway. This is surprising, since this pathway is best known for maintaining undifferentiated germline stem cells/progenitors. Through a combination of genetics, tissue-specific transcriptome analysis, and functional studies of candidate genes, we uncovered a possible explanation for this unexpected role of GLP-1/Notch. We propose that GLP-1/Notch promotes reprograming by activating specific genes, silenced by the Polycomb repressive complex 2 (PRC2), and identify the conserved histone demethylase UTX-1 as a crucial GLP-1/Notch target facilitating reprograming. These findings have wide implications, ranging from development to diseases associated with abnormal Notch signaling.

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Spalt modifies EGFR-mediated induction of chordotonal precursors in the embryonic PNS of Drosophila promoting the development of oenocytes

Development ◽

10.1242/dev.128.5.711 ◽

2001 ◽

Vol 128 (5) ◽

pp. 711-722 ◽

Cited By ~ 3

Author(s):

T.E. Rusten ◽

R. Cantera ◽

J. Urban ◽

G. Technau ◽

F.C. Kafatos ◽

...

Keyword(s):

Nervous System ◽

Cell Fate ◽

System Development ◽

Cell Types ◽

Nervous System Development ◽

Dual Function ◽

Evolutionarily Conserved ◽

A Cell ◽

And Migration

Genes of the spalt family encode nuclear zinc finger proteins. In Drosophila melanogaster, they are necessary for the establishment of head/trunk identity, correct tracheal migration and patterning of the wing imaginal disc. Spalt proteins display a predominant pattern of expression in the nervous system, not only in Drosophila but also in species of fish, mouse, frog and human, suggesting an evolutionarily conserved role for these proteins in nervous system development. Here we show that Spalt works as a cell fate switch between two EGFR-induced cell types, the oenocytes and the precursors of the pentascolopodial organ in the embryonic peripheral nervous system. We show that removal of spalt increases the number of scolopodia, as a result of extra secondary recruitment of precursor cells at the expense of the oenocytes. In addition, the absence of spalt causes defects in the normal migration of the pentascolopodial organ. The dual function of spalt in the development of this organ, recruitment of precursors and migration, is reminiscent of its role in tracheal formation and of the role of a spalt homologue, sem-4, in the Caenorhabditis elegans nervous system.

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NUMB regulates the endocytosis and activity of the anaplastic lymphoma kinase in an isoform-specific manner

Journal of Molecular Cell Biology ◽

10.1093/jmcb/mjz003 ◽

2019 ◽

Vol 11 (11) ◽

pp. 994-1005 ◽

Cited By ~ 2

Author(s):

Ran Wei ◽

Xuguang Liu ◽

Courtney Voss ◽

Wentao Qin ◽

Lina Dagnino ◽

...

Keyword(s):

Cell Fate ◽

Receptor Tyrosine Kinase ◽

Anaplastic Lymphoma Kinase ◽

Degradation Pathway ◽

Anaplastic Lymphoma ◽

Mechanistic Insight ◽

Evolutionarily Conserved ◽

Specific Manner ◽

Insight Into

Abstract NUMB is an evolutionarily conserved protein that plays an important role in cell adhesion, migration, polarity, and cell fate determination. It has also been shown to play a role in the pathogenesis of certain cancers, although it remains controversial whether NUMB functions as an oncoprotein or tumor suppressor. Here, we show that NUMB binds to anaplastic lymphoma kinase (ALK), a receptor tyrosine kinase aberrantly activated in several forms of cancer, and this interaction regulates the endocytosis and activity of ALK. Intriguingly, the function of the NUMB–ALK interaction is isoform-dependent. While both p66-NUMB and p72-NUMB isoforms are capable of mediating the endocytosis of ALK, the former directs ALK to the lysosomal degradation pathway, thus decreasing the overall ALK level and the downstream MAP kinase signal. In contrast, the p72-NUMB isoform promotes ALK recycling back to the plasma membrane, thereby maintaining the kinase in its active state. Our work sheds light on the controversial role of different isoforms of NUMB in tumorigenesis and provides mechanistic insight into ALK regulation.

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Targeting Wnt signaling in colorectal cancer. A Review in the Theme: Cell Signaling: Proteins, Pathways and Mechanisms

AJP Cell Physiology ◽

10.1152/ajpcell.00117.2015 ◽

2015 ◽

Vol 309 (8) ◽

pp. C511-C521 ◽

Cited By ~ 155

Author(s):

Laura Novellasdemunt ◽

Pedro Antas ◽

Vivian S. W. Li

Keyword(s):

Wnt Signaling ◽

Cell Fate ◽

Wnt Pathway ◽

High Throughput Sequencing ◽

Wnt Signaling Pathway ◽

Negative Regulator ◽

Cell Fate Decisions ◽

Stem Cell Maintenance ◽

Evolutionarily Conserved

The evolutionarily conserved Wnt signaling pathway plays essential roles during embryonic development and tissue homeostasis. Notably, comprehensive genetic studies in Drosophila and mice in the past decades have demonstrated the crucial role of Wnt signaling in intestinal stem cell maintenance by regulating proliferation, differentiation, and cell-fate decisions. Wnt signaling has also been implicated in a variety of cancers and other diseases. Loss of the Wnt pathway negative regulator adenomatous polyposis coli (APC) is the hallmark of human colorectal cancers (CRC). Recent advances in high-throughput sequencing further reveal many novel recurrent Wnt pathway mutations in addition to the well-characterized APC and β-catenin mutations in CRC. Despite attractive strategies to develop drugs for Wnt signaling, major hurdles in therapeutic intervention of the pathway persist. Here we discuss the Wnt-activating mechanisms in CRC and review the current advances and challenges in drug discovery.

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RBP-Jκ-Dependent Notch Signaling Is Dispensable for Mouse Early Embryonic Development

Molecular and Cellular Biology ◽

10.1128/mcb.00319-06 ◽

2006 ◽

Vol 26 (13) ◽

pp. 4769-4774 ◽

Cited By ~ 33

Author(s):

Céline Souilhol ◽

Sarah Cormier ◽

Kenji Tanigaki ◽

Charles Babinet ◽

Michel Cohen-Tannoudji

Keyword(s):

Embryonic Development ◽

Notch Signaling ◽

Signaling Pathway ◽

Cell Fate ◽

Notch Pathway ◽

Notch Signaling Pathway ◽

Preimplantation Embryos ◽

Cell Fate Specification ◽

Fate Specification ◽

Evolutionarily Conserved

ABSTRACT The Notch signaling pathway is an evolutionarily conserved signaling system which has been shown to be essential in cell fate specification and in numerous aspects of embryonic development in all metazoans thus far studied. We recently demonstrated that several components of the Notch signaling pathway, including the four Notch receptors and their five ligands known in mammals, are expressed in mouse oocytes, in mouse preimplantation embryos, or both. This suggested a possible implication of the Notch pathway in the first cell fate specification of the dividing mouse embryo, which results in the formation of the blastocyst. To address this issue directly, we generated zygotes in which both the maternal and the zygotic expression of Rbpsuh, a key element of the core Notch signaling pathway, were abrogated. We find that such zygotes give rise to blastocysts which implant and develop normally. Nevertheless, after gastrulation, these embryos die around midgestation, similarly to Rbpsuh-null mutants. This demonstrates that the RBP-Jκ-dependent pathway, otherwise called the canonical Notch pathway, is dispensable for blastocyst morphogenesis and the establishment of the three germ layers, ectoderm, endoderm, and mesoderm. These results are discussed in the light of recent observations which have challenged this conclusion.

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De novo morphogenesis of testis tissue: an improved bioassay to investigate the role of VEGF165 during testis formation

Reproduction ◽

10.1530/rep-13-0303 ◽

2014 ◽

Vol 148 (1) ◽

pp. 109-117 ◽

Cited By ~ 17

Author(s):

Camila Dores ◽

Ina Dobrinski

Keyword(s):

Blood Vessel ◽

Cell Suspension ◽

Germ Cells ◽

De Novo ◽

Donor Cell ◽

Seminiferous Tubules ◽

Tissue Formation ◽

Tubule Formation ◽

Testis Tissue

De novo formation of testis tissue from single-cell suspensions allows manipulation of different testicular compartments before grafting to study testicular development and the spermatogonial stem cell niche. However, the low percentages of newly formed seminiferous tubules supporting complete spermatogenesis and lack of a defined protocol have limited the use of this bioassay. Low spermatogenic efficiency in de novo formed tissue could result from the scarcity of germ cells in the donor cell suspension, cell damage caused by handling or from hypoxia during tissue formation in the host environment. In this study, we compared different proportions of spermatogonia in the donor cell suspension and the use of Matrigel as a scaffold to support de novo tissue formation and spermatogenesis. Then, we used the system to investigate the role of vascular endothelial growth factor 165 (VEGF165) during testicular morphogenesis on blood vessel and seminiferous tubule formation, and on presence of germ cells in the de novo developed tubules. Our results show that donor cell pellets with 10×106 porcine neonatal testicular cells in Matrigel efficiently formed testis tissue de novo. Contrary to what was expected, the enrichment of the cell suspension with germ cells did not result in higher numbers of tubules supporting spermatogenesis. The addition of VEGF165 did not improve blood vessel or tubule formation, but it enhanced the number of tubules containing spermatogonia. These results indicate that spermatogenic efficiency was improved by the addition of Matrigel, and that VEGF165 may have a protective role supporting germ cell establishment in their niche.

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SIRT1 Expression and Regulation in the Primate Testis

International Journal of Molecular Sciences ◽

10.3390/ijms22063207 ◽

2021 ◽

Vol 22 (6) ◽

pp. 3207

Author(s):

Fazal Wahab ◽

Ignacio Rodriguez Polo ◽

Rüdiger Behr

Keyword(s):

Germ Cells ◽

Rhesus Macaques ◽

Sirtuin 1 ◽

Primate Species ◽

Seminiferous Tubules ◽

Sirt1 Expression ◽

Protein Substrates ◽

Development And Differentiation ◽

Endocrine Factor

The epigenetic mechanisms controlling germ cell development and differentiation are still not well understood. Sirtuin-1 (SIRT1) is a nicotinamide adenosine dinucleotide (NAD)-dependent histone deacetylase and belongs to the sirtuin family of deacetylases. It catalyzes the removal of acetyl groups from a number of protein substrates. Some studies reported a role of SIRT1 in the central and peripheral regulation of reproduction in various non-primate species. However, testicular SIRT1 expression and its possible role in the testis have not been analyzed in primates. Here, we document expression of SIRT1 in testes of different primates and some non-primate species. SIRT1 is expressed mainly in the cells of seminiferous tubules, particularly in germ cells. The majority of SIRT1-positive germ cells were in the meiotic and postmeiotic phase of differentiation. However, SIRT1 expression was also observed in selected premeiotic germ cells, i.e., spermatogonia. SIRT1 co-localized in spermatogonia with irisin, an endocrine factor specifically expressed in primate spermatogonia. In marmoset testicular explant cultures, SIRT1 transcript levels are upregulated by the addition of irisin as compared to untreated controls explants. Rhesus macaques are seasonal breeders with high testicular activity in winter and low testicular activity in summer. Of note, SIRT1 mRNA and SIRT1 protein expression are changed between nonbreeding (low spermatogenesis) and breeding (high spermatogenesis) season. Our data suggest that SIRT1 is a relevant factor for the regulation of spermatogenesis in primates. Further mechanistic studies are required to better understand the role of SIRT1 during spermatogenesis.

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Notch Signaling in T-Cell Development and T-ALL

ISRN Hematology ◽

10.5402/2011/921706 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Xiaoyu Li ◽

Harald von Boehmer

Keyword(s):

T Cell ◽

Notch Signaling ◽

Signaling Pathway ◽

Cell Fate ◽

Notch Signaling Pathway ◽

Lineage Specification ◽

Evolutionarily Conserved ◽

Multiple Levels ◽

Multicellular Organisms ◽

T Cell Maturation

The Notch signaling pathway is an evolutionarily conserved cell signaling system present in most multicellular organisms, as it controls cell fate specification by regulating cell proliferation, differentiation, apoptosis, and survival. Regulation of the Notch signaling pathway can be achieved at multiple levels. Notch proteins are involved in lineage fate decisions in a variety of tissues in various species. Notch is essential for T lineage cell differentiation including T versus B and αβ versus γδ lineage specification. In this paper, we discuss Notch signaling in normal T-cell maturation and differentiation as well as in T-cell acute lymphoblastic lymphoma/leukemia.

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PINK1/Parkin-Mediated Mitophagy Promotes Resistance to Sonodynamic Therapy

Cellular Physiology and Biochemistry ◽

10.1159/000493629 ◽

2018 ◽

Vol 49 (5) ◽

pp. 1825-1839 ◽

Cited By ~ 6

Author(s):

Lin Song ◽

Yongmin Huang ◽

Xuandi Hou ◽

Yaoheng Yang ◽

Shashwati Kala ◽

...

Keyword(s):

Cell Death ◽

Cell Fate ◽

Immunofluorescence Microscopy ◽

Aminolevulinic Acid ◽

Mitochondrial Dynamics ◽

Breast Adenocarcinoma ◽

Sonodynamic Therapy ◽

Confocal Immunofluorescence Microscopy ◽

Confocal Immunofluorescence ◽

Mcf 7

Background/Aims: Sonodynamic therapy (SDT), based on the synergistic effect of low-intensity ultrasound and sonosensitizer, is a potential approach for non-invasive treatment of cancers. In SDT, mitochondria played a crucial role in cell fate determination. However, mitochondrial activities and their response to SDT remain elusive. The purpose of this study was to examine the response of mitochondria to SDT in tumor cells. Methods: A human breast adenocarcinoma cell line - MCF-7 cells were subjected to 5-aminolevulinic acid (ALA)-SDT, with an average ultrasonic intensity of 0.25W/cm2. Mitochondrial dynamics and redox balance were examined by confocal immunofluorescence microscopy and western blot. The occurrence of mitophagy was determined by confocal immunofluorescence microscopy. Results: Our results showed that ALA-SDT could induce mitochondrial dysfunction through mitochondrial depolarization and fragmentation and lead to mitophagy. The Parkin-dependent signaling pathway was involved and promoted resistance to ALA-SDT induced cell death. Finally, excessive production of ROS was found to be necessary for the initiation of mitophagy. Conclusion: Taken together, we conclude that ROS produced by 5-ALA-SDT could initiate PINK1/Parkin-mediated mitophagy which may exert a protective effect against 5-ALA-SDT-induced cell death in MCF-7 cells.

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Wnt/β-catenin signaling is an evolutionarily conserved determinant of chordate dorsal organizer

eLife ◽

10.7554/elife.56817 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 2

Author(s):

Iryna Kozmikova ◽

Zbynek Kozmik

Keyword(s):

Cell Fate ◽

Current View ◽

Specific Gene ◽

Axis Formation ◽

Dependent Manner ◽

Evolutionarily Conserved ◽

Dorsal Axis ◽

Dorsal Cells ◽

Dorsal Cell Fate

Deciphering the mechanisms of axis formation in amphioxus is a key step to understanding the evolution of chordate body plan. The current view is that Nodal signaling is the only factor promoting the dorsal axis specification in the amphioxus, whereas Wnt/β-catenin signaling plays no role in this process. Here, we re-examined the role of Wnt/βcatenin signaling in the dorsal/ventral patterning of amphioxus embryo. We demonstrated that the spatial activity of Wnt/β-catenin signaling is located in presumptive dorsal cells from cleavage to gastrula stage, and provided functional evidence that Wnt/β-catenin signaling is necessary for the specification of dorsal cell fate in a stage-dependent manner. Microinjection of Wnt8 and Wnt11 mRNA induced ectopic dorsal axis in neurulae and larvae. Finally, we demonstrated that Nodal and Wnt/β-catenin signaling cooperate to promote the dorsal-specific gene expression in amphioxus gastrula. Our study reveals high evolutionary conservation of dorsal organizer formation in the chordate lineage.

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