Primordial germ cells (PGCs) arise elsewhere in the embryo and migrate into developing gonadal ridges during embryonic development. In several model animals, formation and migration patterns of PGCs have been studied, and it is known that these patterns vary. Sturgeons (genus Acipenser) have great potential for comparative and evolutionary studies of development. Sturgeons belong to the super class Actinoptergii, and their developmental pattern is similar to that of amphibians, although their phylogenetic position is an out-group to teleost fishes. Here, we reveal an injection technique for sturgeon eggs allowing visualization of germplasm and PGCs. Using this technique, we demonstrate that the PGCs are generated at the vegetal pole of the egg and they migrate on the yolky cell mass toward the gonadal ridge. We also provide evidence showing that PGCs are specified by inheritance of maternally supplied germplasm. Furthermore, we demonstrate that the migratory mechanism is well-conserved between sturgeon and other remotely related teleosts, such as goldfish, by a single PGCs transplantation (SPT) assay. The mode of PGCs specification in sturgeon is similar to that of anurans, but the migration pattern resembles that of teleosts.
- MeSH
- Models, Biological * MeSH
- Embryo, Nonmammalian cytology embryology MeSH
- Embryonic Development physiology MeSH
- Cell Movement physiology MeSH
- Fishes embryology MeSH
- Germ Cells cytology metabolism MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
The ERK (extracellular signal-regulated kinases) cascade has an evolutionarily conserved three tier architecture consisting of protein kinases Raf, MEK (MAPK/ERK kinase) and ERK. Following activation, ERK phosphorylates various cellular elements leading to diverse cellular responses. Downstream of ERK the family of p90 ribosomal S6 kinases (RSKs) has been proven to be an important conveyor of ERK signaling, however, little is known if ERK and RSK coordinate their functions to generate a specific biological response. Here we show that in epithelial cells conditional activation of the ERK pathway causes phenotypic conversion of epithelial cells to autonomously migrating cells. This process involves two sequential steps characterized by loss of apical-basal polarity followed by cell scattering. The activation of ERK, but not RSK, is sufficient for the execution of the first step and it requires calpain mediated remodeling of actin cytoskeleton. Conversely, RSK regulates the successive stage characterized by cell-cell contact weakening and increased cellular migration. Thus, ERK and RSK regulate different cellular subprograms and coordinated execution of these subprograms in time generates a relevant biological response. Our data also suggest that the mechanism by which the ERK pathway controls a cellular response may be distributed between ERK and RSK, rather than being elicited by a single effector kinase.
- MeSH
- Cell Line MeSH
- Epithelial Cells cytology metabolism MeSH
- Extracellular Signal-Regulated MAP Kinases metabolism MeSH
- Cadherins metabolism MeSH
- Calpain metabolism MeSH
- Ribosomal Protein S6 Kinases, 90-kDa metabolism MeSH
- Humans MeSH
- MAP Kinase Signaling System MeSH
- Intercellular Junctions metabolism MeSH
- Cell Movement MeSH
- Cell Polarity MeSH
- Dogs MeSH
- Signal Transduction * MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Dogs MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Dynamic polarisation of tumour cells is essential for metastasis. While the role of polarisation during dedifferentiation and migration is well established, polarisation of metastasising tumour cells during phases of detachment has not been investigated. Here we identify and characterise a type of polarisation maintained by single cells in liquid phase termed single-cell (sc) polarity and investigate its role during metastasis. We demonstrate that sc polarity is an inherent feature of cells from different tumour entities that is observed in circulating tumour cells in patients. Functionally, we propose that the sc pole is directly involved in early attachment, thereby affecting adhesion, transmigration and metastasis. In vivo, the metastatic capacity of cell lines correlates with the extent of sc polarisation. By manipulating sc polarity regulators and by generic depolarisation, we show that sc polarity prior to migration affects transmigration and metastasis in vitro and in vivo.
- MeSH
- Humans MeSH
- Neoplasm Metastasis pathology physiopathology MeSH
- Mice, Inbred C57BL MeSH
- Cell Line, Tumor MeSH
- Neoplastic Cells, Circulating pathology MeSH
- Neoplasms pathology physiopathology MeSH
- Cell Movement MeSH
- Cell Polarity * MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Immunization of rats with mouse alpha-foetoprotein has been earlier shown to induce the antibody response to self AFP or rats. In this work a single injection of AFPm resulted in termination of natural tolerance of effector T-cells to AFPr, as shown by the macrophage migration inhibition test using peritoneal exudate cells from immunized animals. A significant reaction was elicited by both AFPm and AFPr in the course of primary, secondary and third immunization with AFPm. Pronounced MMI reaction to AFPm and AFPr has developed when AFPr was used as a booster antigen after primary injection with AFPm. Both the kinetics and magnitude of cell-mediated response to heterologous and self AFP injected either in CFA or without it were studied by the MMI test. T-cells of immune PEC were demonstrated by T-B separation to be responsible for MMI elicited by AFPm and AFPr.
- MeSH
- alpha-Fetoproteins immunology MeSH
- Ascitic Fluid cytology MeSH
- B-Lymphocytes immunology MeSH
- Freund's Adjuvant MeSH
- Cell Migration Inhibition * MeSH
- Rats MeSH
- Macrophages immunology MeSH
- Mice MeSH
- Antibodies analysis MeSH
- T-Lymphocytes immunology MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Male MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
Proliferation and migration of retinal endothelial cells (RECs) contribute to the development of diabetic retinopathy. PLAG1 (pleomorphic adenoma gene 1) functions as a zinc-finger transcription factor to participate in the development of lipoblastomas or pleomorphic adenomas of the salivary glands through regulation of cell proliferation and migration. The role of PLAG1 in diabetic retinopathy was investigated in this study. Firstly, RECs were induced under high glucose conditions, which caused reduction in viability and induction of apoptosis in the RECs. Indeed, PLAG1 was elevated in high glucosetreated RECs. Functional assays showed that silence of PLAG1 increased viability and suppressed apoptosis in high glucose-induced RECs, accompanied with up-regulation of Bcl-2 and down-regulation of Bax and cleaved caspase-3. Moreover, migration of RECs was promoted by high glucose conditions, while repressed by knockdown of PLAG1. High glucose also triggered angiogenesis of RECs through up-regulation of vascular endothelial growth factor (VEGF). However, interference of PLAG1 reduced VEGF expression to retard the angiogenesis. Silence of PLAG1 also attenuated high glucose-induced up-regulation of Wnt3a, β-catenin and c-Myc in RECs. Moreover, silence of PLAG1 ameliorated histopathological changes in the retina of STZ-induced diabetic rats through down-regulation of β-catenin. In conclusion, knockdown of PLAG1 suppressed high glucose-induced angiogenesis and migration of RECs, and attenuated diabetic retinopathy by inactivation of Wnt/ β-catenin signalling.
- MeSH
- beta Catenin metabolism MeSH
- Diabetic Retinopathy * MeSH
- DNA-Binding Proteins metabolism MeSH
- Endothelial Cells metabolism MeSH
- Diabetes Mellitus, Experimental * MeSH
- Glucose toxicity MeSH
- Caspase 3 MeSH
- Rats MeSH
- Neovascularization, Pathologic MeSH
- bcl-2-Associated X Protein MeSH
- Retina metabolism MeSH
- Wnt Signaling Pathway MeSH
- Transcription Factors MeSH
- Vascular Endothelial Growth Factor A MeSH
- Zinc MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
We applied the alkaline version of the single-cell gel electrophoresis (comet) assay to roots and leaves of tobacco (Nicotiana tabacum var. xanthi) seedlings or isolated leaf nuclei treated with: (1) the alkylating agent ethyl methanesulphonate, (2) necrotic heat treatments at 50 degrees C, and (3) DNase-I. All three treatments induced a dose-dependent increase in DNA migration, expressed as percentage of tail DNA. A comparison of the fluorochrome DNA dyes ethidium bromide, DAPI and YOYO-1 demonstrated that for the alkaline version of the comet assay in plants, the commonly used fluorescent dye ethidium bromide can be used with the same efficiency as DAPI or YOYO-1.
- MeSH
- Alkylating Agents toxicity MeSH
- Single-Cell Analysis MeSH
- Staining and Labeling methods MeSH
- Benzoxazoles chemistry MeSH
- Quinolinium Compounds chemistry MeSH
- Deoxyribonuclease I metabolism pharmacology MeSH
- DNA, Plant analysis chemistry MeSH
- Ethidium chemistry MeSH
- Ethyl Methanesulfonate toxicity MeSH
- Fluorescent Dyes MeSH
- Indoles chemistry MeSH
- Comet Assay MeSH
- Plant Roots chemistry drug effects MeSH
- Plant Leaves chemistry drug effects MeSH
- Seedlings chemistry drug effects MeSH
- Nicotiana chemistry drug effects MeSH
- Hot Temperature MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
RNF213/Mysterin has been identified as a susceptibility gene for moyamoya disease, a cerebrovascular disease characterized by occlusive lesions in the circle of Willis. The p.R4810K (rs112735431) variant is a founder polymorphism that is strongly associated with moyamoya disease in East Asia. Many non-p.R4810K rare variants of RNF213 have been identified in white moyamoya disease patients, although the ethnic mutations have not been investigated in this population. In the present study, we screened for RNF213 variants in 19 Slovakian and Czech moyamoya disease patients. A total of 69 RNF213 coding exons were directly sequenced in 18 probands and one relative who suffered from moyamoya disease in Slovakia and the Czech Republic. We previously reported one proband harboring RNF213 p.D4013N. Results from the present study identified four rare variants other than p.D4013N (p.R4019C, p.E4042K, p.V4146A, and p.W4677L) in four of the patients. P.V4146A was determined to be a novel de novo mutation, and p.R4019C and p.E4042K were identified as double mutations inherited on the same allele. P.W4677L, found in two moyamoya disease patients and an unaffected subject in the same pedigree, was a rare single nucleotide polymorphism. Functional analysis showed that RNF213 p.D4013N, p.R4019C and p.V4146A-transfected human umbilical vein endothelial cells displayed significant lowered migration, and RNF213 p.V4146A significantly reduced tube formation, indicating that these are disease-causing mutations. Results from the present study identified RNF213 rare variants in 22.2% (4/18 probands) of Slovakian and Czech moyamoya disease patients, confirming that RNF213 may also be a major causative gene in a relative large population of white patients.
- MeSH
- Adenosine Triphosphatases genetics metabolism MeSH
- Alleles MeSH
- White People genetics MeSH
- Child MeSH
- Adult MeSH
- Human Umbilical Vein Endothelial Cells MeSH
- Exons MeSH
- Genotype MeSH
- Haplotypes MeSH
- Polymorphism, Single Nucleotide MeSH
- Middle Aged MeSH
- Humans MeSH
- Magnetic Resonance Angiography MeSH
- Young Adult MeSH
- Moyamoya Disease genetics pathology MeSH
- Cell Movement MeSH
- Pedigree MeSH
- Sequence Analysis, DNA MeSH
- Ubiquitin-Protein Ligases genetics metabolism MeSH
- Check Tag
- Child MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
- Slovakia MeSH
Central nervous system neurons become postmitotic when radial glia cells divide to form neuroblasts. Neuroblasts may migrate away from the ventricle radially along glia fibers, in various directions or even across the midline. We present four cases of unusual migration that are variably connected to either pathology or formation of new populations of neurons with new connectivities. One of the best-known cases of radial migration involves granule cells that migrate from the external granule cell layer along radial Bergman glia fibers to become mature internal granule cells. In various medulloblastoma cases this migration does not occur and transforms the external granule cell layer into a rapidly growing tumor. Among the ocular motor neurons is one unique population that undergoes a contralateral migration and uniquely innervates the superior rectus and levator palpebrae muscles. In humans, a mutation of a single gene ubiquitously expressed in all cells, induces innervation defects only in this unique motor neuron population, leading to inability to elevate eyes or upper eyelids. One of the best-known cases for longitudinal migration is the facial branchial motor (FBM) neurons and the overlapping inner ear efferent population. We describe here molecular cues that are needed for the caudal migration of FBM to segregate these motor neurons from the differently migrating inner ear efferent population. Finally, we describe unusual migration of inner ear spiral ganglion neurons that result in aberrant connections with disruption of frequency presentation. Combined, these data identify unique migratory properties of various neuronal populations that allow them to adopt new connections but also sets them up for unique pathologies.
- Publication type
- Journal Article MeSH
- Review MeSH
Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection).
- MeSH
- Acetyltransferases genetics MeSH
- Genome, Human * MeSH
- Haplotypes MeSH
- Hemorrhagic Fevers, Viral genetics MeSH
- Polymorphism, Single Nucleotide MeSH
- Duffy Blood-Group System genetics MeSH
- Humans MeSH
- Malaria genetics MeSH
- Minichromosome Maintenance Complex Component 6 genetics MeSH
- Meningitis genetics MeSH
- Human Migration * MeSH
- Proteins genetics MeSH
- Receptors, Cell Surface genetics MeSH
- Receptors, G-Protein-Coupled genetics MeSH
- Selection, Genetic * MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Africa MeSH
