-
BMC Genomics Mar 2024Satellite cells are myogenic precursor cells in adult skeletal muscle and play a crucial role in skeletal muscle regeneration, maintenance, and growth. Like embryonic...
BACKGROUND
Satellite cells are myogenic precursor cells in adult skeletal muscle and play a crucial role in skeletal muscle regeneration, maintenance, and growth. Like embryonic myoblasts, satellite cells have the ability to proliferate, differentiate, and fuse to form multinucleated myofibers. In this study, we aimed to identify additional transcription factors that control gene expression during bovine satellite cell proliferation and differentiation.
RESULTS
Using chromatin immunoprecipitation followed by sequencing, we identified 56,973 and 54,470 genomic regions marked with both the histone modifications H3K4me1 and H3K27ac, which were considered active enhancers, and 50,956 and 59,174 genomic regions marked with H3K27me3, which were considered repressed enhancers, in proliferating and differentiating bovine satellite cells, respectively. In addition, we identified 1,216 and 1,171 super-enhancers in proliferating and differentiating bovine satellite cells, respectively. Analyzing these enhancers showed that in proliferating bovine satellite cells, active enhancers were associated with genes stimulating cell proliferation or inhibiting myoblast differentiation whereas repressed enhancers were associated with genes essential for myoblast differentiation, and that in differentiating satellite cells, active enhancers were associated with genes essential for myoblast differentiation or muscle contraction whereas repressed enhancers were associated with genes stimulating cell proliferation or inhibiting myoblast differentiation. Active enhancers in proliferating bovine satellite cells were enriched with binding sites for many transcription factors such as MYF5 and the AP-1 family transcription factors; active enhancers in differentiating bovine satellite cells were enriched with binding sites for many transcription factors such as MYOG and TFAP4; and repressed enhancers in both proliferating and differentiating bovine satellite cells were enriched with binding sites for NF-kB, ZEB-1, and several other transcription factors. The role of TFAP4 in satellite cell or myoblast differentiation was previously unknown, and through gene knockdown and overexpression, we experimentally validated a critical role for TFAP4 in the differentiation and fusion of bovine satellite cells into myofibers.
CONCLUSIONS
Satellite cell proliferation and differentiation are controlled by many transcription factors such as AP-1, TFAP4, NF-kB, and ZEB-1 whose roles in these processes were previously unknown in addition to those transcription factors such as MYF5 and MYOG whose roles in these processes are widely known.
Topics: Animals; Cattle; Chromatin; NF-kappa B; Transcription Factor AP-1; Cell Differentiation; Cell Proliferation; Satellite Cells, Skeletal Muscle; Muscle Development
PubMed: 38475725
DOI: 10.1186/s12864-024-10189-2 -
European Journal of Immunology Jun 2017Natural killer (NK) cells are cytotoxic lymphocytes that selectively respond against abnormal cells. Human cytomegalovirus (HCMV) infection causes expansion of NKG2C...
Natural killer (NK) cells are cytotoxic lymphocytes that selectively respond against abnormal cells. Human cytomegalovirus (HCMV) infection causes expansion of NKG2C CD57 NK cells in vivo and NKG2C NK cells proliferate when cultured with HCMV-infected cells. This raises the possibility of an NK-cell subset selectively responding against a specific pathogen and accruing memory. To test this possibility, we compared proliferation, natural cytotoxicity and interferon-γ (IFN-γ) production of NK cells from HCMV-seropositive and HCMV-seronegative individuals co-cultured with HCMV-infected or uninfected MRC-5 cells. There was no significant difference in proliferation of NK cells from HCMV-seropositive or seronegative individuals against uninfected MRC-5 cells, but significantly more NK cells from the HCMV-seropositive group proliferated in response to HCMV-infected MRC-5 cells. Natural cytotoxicity of NK cells against K562 cells increased following co-culture with HCMV-infected versus uninfected MRC-5 only for the HCMV-seropositive group. After co-culture with HCMV-infected MRC-5 cells, proliferating NK cells from HCMV-seropositive donors selectively produced IFN-γ when re-exposed to HCMV-infected MRC-5 cells. Both NKG2C and NKG2C NK cells proliferated in co-culture with HCMV-infected MRC-5 cells, with the fraction of proliferating NKG2C NK cells directly correlating with the circulating NKG2C fraction. These data illustrate an at least partly NKG2C-independent human NK-cell memory-type response against HCMV.
Topics: CD57 Antigens; Cell Proliferation; Coculture Techniques; Cytomegalovirus; Cytomegalovirus Infections; Fibroblasts; Humans; Immunologic Memory; Interferon-gamma; K562 Cells; Killer Cells, Natural; Lymphocyte Activation; NK Cell Lectin-Like Receptor Subfamily C
PubMed: 28475279
DOI: 10.1002/eji.201646819 -
Parasitology Sep 2023is an industrially significant protozoan parasite of Manila clam, . So far, various media, based on Dulbecco's Modified Eagle Medium and Ham's F-12 nutrient mixture...
is an industrially significant protozoan parasite of Manila clam, . So far, various media, based on Dulbecco's Modified Eagle Medium and Ham's F-12 nutrient mixture with supplementation of fetal bovine serum (FBS), have been developed to proliferate the parasitizing trophozoite stage of . The present study showed that did not proliferate in FBS-deficient Perkinsus broth medium (PBMΔF), but proliferated well in PBMΔF supplemented with tissue extract of host Manila clams, indicating that FBS and Manila clam tissue contained molecule(s) required for proliferation. Preliminary characterization suggested that the host-derived molecule(s) was a heat-stable molecule(s) with a molecular weight of less than 3 kDa, and finally a single molecule required for the proliferation was purified by high-performance liquid chromatography processes. High-resolution electrospray ionization mass spectrometry and nuclear magnetic resonance analyses identified this molecule as glycine betaine (=trimethylglycine), and the requirement of this molecule for proliferation was confirmed by an assay using chemically synthesized, standard glycine betaine. Although glycine betaine was required for the proliferation of all examined species, supplementation of glycine betaine precursors, such as choline and betaine aldehyde, enhanced the proliferation of 4 species ( and ), but not of 2 others ( and ). Thus, it was concluded that the ability to biosynthesise glycine betaine from its precursors varied among species, and that and lack the ability required to biosynthesize glycine betaine for proliferation.
Topics: Animals; Parasites; Betaine; Bivalvia; Trophozoites; Cell Proliferation; Alveolata
PubMed: 37565486
DOI: 10.1017/S0031182023000768 -
BMC Nephrology Jan 2014Nephrotic syndrome (NS) is pathological condition characterized by heavy proteinuria. Our study investigates hypothesis that change in cell proliferation of proximal...
BACKGROUND
Nephrotic syndrome (NS) is pathological condition characterized by heavy proteinuria. Our study investigates hypothesis that change in cell proliferation of proximal tubules influences primary cilia structure and function and promotes cystogenesis in congenital nephrotic syndrome of the Finnish type (CNF) and focal segmental glomerulosclerosis (FSGS).
METHODS
CNF kidneys were analyzed genetically. Proliferation (Ki-67), apoptosis (caspase-3), and primary cilia (α-tubulin) length and structure were analyzed immunohistochemically and ultrastructurally in healthy, CNF and FSGS kidneys. Cyst diameters were measured and correlated with proliferation index.
RESULTS
Proximal tubules cells of healthy kidneys did not proliferate. In nephrotic kidneys, tubules with apparently normal diameter covered by cuboidal/columnar epithelium (PTNC) contained 81.54% of proliferating cells in CNF and 36.18% in FSGS, while cysts covered with columnar epithelium (CC) contained 37.52% of proliferating cells in CNF and 45.23% in FSGS. The largest cysts, covered with squamous epithelium (CS) had 11.54% of proliferating cells in CNF and 13.76% in FSGS. Increase in cysts diameter correlated with changes in proliferation index, tubular cells shape, primary cilia formation and appearance of apoptotic cells.
CONCLUSIONS
We present a novel histopathological data on the structure and possible changes in function of tubular cell in NS kidneys during cystogenesis. We suggest existence of common principles of cystogenesis in CNF and FSGS kidneys, including serious disturbances of tubular cells proliferation and apoptosis, and faulty primary cilia signaling leading to deterioration of proteinuria in NS kidneys.
Topics: Child; Female; Glomerulosclerosis, Focal Segmental; Humans; Infant; Kidney Tubules, Proximal; Male; Nephrotic Syndrome; Proteinuria
PubMed: 24397250
DOI: 10.1186/1471-2369-15-3 -
Proceedings of the National Academy of... Feb 1991Analysis of a simian virus 40-immortalized colony-stimulating factor 1 (CSF-1) -dependent macrophage cell line (BAC1.2F5) and independently arising autonomous mutants...
Analysis of a simian virus 40-immortalized colony-stimulating factor 1 (CSF-1) -dependent macrophage cell line (BAC1.2F5) and independently arising autonomous mutants derived from it (aut4A, aut4A.1, aut2A, and aut2A.1) revealed distinct phenotypes. The parental line, BAC1.2F5, is dependent on CSF-1 for survival and growth. Of the mutants derived from BAC1.2F5, aut4A has lost the requirement of CSF-1 for survival; aut4A.1 (derived from aut4A) and aut2A grow in the absence of growth factor but proliferate more rapidly in its presence, and aut2A.1 (derived from aut2A) produces CSF-1 and proliferates as rapidly in the presence as in the absence of exogeneous CSF-1. The separation of the CSF-1 requirement for survival and proliferation observed in aut4A is also observed in a temperature-sensitive (ts) mutant tsgro1. At the nonpermissive temperature, tsgro1 cell proliferation is arrested, but the cells survive provided CSF-1 is present. The four cellular phenotypes observed--immortalization, loss of growth factor requirement for survival, loss of growth factor requirement for proliferation, and loss of growth factor-stimulated proliferation--indicate a divergence of the pathways of growth factor-regulated survival and proliferation and may represent phenotypes occurring at intermediate stages in tumor-cell progression.
Topics: Animals; Cell Division; Cell Line; Cell Survival; Kinetics; Macrophage Colony-Stimulating Factor; Macrophages; Mice; Mutation
PubMed: 1996348
DOI: 10.1073/pnas.88.4.1474 -
Neuroscience Sep 2009In the central nervous system (CNS), adenosine 5'-triphosphate (ATP) induces the synthesis and release of neurotrophic factors, cell proliferation, and differentiation....
In the central nervous system (CNS), adenosine 5'-triphosphate (ATP) induces the synthesis and release of neurotrophic factors, cell proliferation, and differentiation. The olfactory system is one site where multipotent progenitor cells continue to proliferate and differentiate into neurons throughout life. We tested the hypothesis that ATP initiates proliferation in olfactory epithelium by measuring 5-bromo-2-deoxyuridine incorporation. Adult mice were pre-treated intraperitoneally (i.p.) or intranasally with saline or purinergic receptor antagonists (pyridoxal-phosphate-6-azophenyl-2',4'-disulfonate+suramin) 30 min prior to nasal instillation of ATP, uridine 5'-triphosphate (UTP), adenosine 5'-(3-thiotriphosphate) (ATP gamma S) or saline (0 h). Mice received three injections of 5-bromo-2-deoxyuridine between 42 and 46 h, and were sacrificed at 2, 9 or 16 days post-ATP instillation. ATP, UTP or ATP gamma S significantly increased 5-bromo-2-deoxyuridine incorporation compared to intranasal saline controls in groups pre-treated with saline. Saline, ATP, UTP or ATP gamma S instillation did not significantly increase 5-bromo-2-deoxyuridine incorporation in groups pre-treated with purinergic receptor antagonists. Similar results were observed in neonates and in a cultured slice preparation. Intranasal instillation of ATP also increased the protein levels of proliferating cell nuclear antigen in adults. Pre-treatment with purinergic receptor antagonists inhibited the ATP-induced increase in proliferating cell nuclear antigen. In adults, a subset of the cells that incorporated 5-bromo-2-deoxyuridine was immunoreactive to neuronal markers mammalian achaete-schute homolog 1, growth-associated protein 43, and olfactory marker protein at 2, 9, and 16 days, respectively. Collectively, these data indicate that purinergic receptor activation induces proliferation and neuronal differentiation in the mouse olfactory epithelium. We propose that extracellular ATP released upon injury could induce proliferation and promote the neuroregeneration of the olfactory epithelium.
Topics: Adenosine Triphosphate; Animals; Animals, Newborn; Biomarkers; Bromodeoxyuridine; Cell Differentiation; Cell Proliferation; Male; Mice; Nerve Regeneration; Neurogenesis; Olfactory Mucosa; Organ Culture Techniques; Proliferating Cell Nuclear Antigen; Purinergic Agonists; Purinergic Antagonists; Receptors, Purinergic; Sensory Receptor Cells; Stem Cells; Suramin; Uridine Triphosphate
PubMed: 19555741
DOI: 10.1016/j.neuroscience.2009.06.040 -
BMC Cell Biology Mar 2018Satellite cells (SC) and their descendants, muscle precursor cells (MPC), play a key role in postnatal muscle development, regeneration, and plasticity. Several studies...
BACKGROUND
Satellite cells (SC) and their descendants, muscle precursor cells (MPC), play a key role in postnatal muscle development, regeneration, and plasticity. Several studies have provided evidence that SC and MPC represent a heterogeneous population differing in their biochemical and functional properties. The identification and characterization of functionally divergent SC subpopulations should help to reveal the precise involvement of SC/MPC in these myogenic processes. The aim of the present work was therefore to separate SC subpopulations by using Percoll gradients and to characterize their myogenic marker profiles and their functional properties (adhesion, proliferation, and differentiation).
RESULTS
SC/MPC from muscles of 4-day-old piglets were isolated by trypsin digestion and enriched by Percoll density gradient centrifugation. A mixed myogenic cell population was obtained from the 40/70% interface (termed: mixed P40/70) of a 25/40/70% Percoll gradient. Thereafter, by using a more stepped 25/40/50/70% Percoll gradient, mixed P40/70 was divided into subpopulation 40/50 (SP40/50) collected from the 40/50% interface and subpopulation 50/70 (SP50/70) collected from the 50/70% interface. All three isolated populations proliferated and showed a myogenic phenotype characterized by the ability to express myogenic markers (Pax7, MyoD1, Desmin, and MyoG) and to differentiate into myotubes. However, compared with mixed P40/70, SP40/50 and SP50/70 exhibited distinct functional behavior. Growth kinetic curves over 90 h obtained by the xCELLigence system and proliferation assays revealed that SP40/50 and mixed P40/70 constituted a fast adhering and fast proliferating phenotype. In contrast, SP50/70 showed considerably slower adhesion and proliferation. The fast-proliferating SP40/50 showed the highest myogenic differentiation potential with higher fusion rates and the formation of more middle-sized and large myotubes.
CONCLUSIONS
The described Percoll density gradient centrifugation represents a useful tool for subdividing pig SC/MPC populations with divergent myogenic functions. The physiological role of SC subpopulations during myogenesis and the interaction of these populations can now be analyzed to a greater extent, shedding light on postnatal growth variations in pigs and probably in other animals.
Topics: Animals; Biomarkers; Cell Adhesion; Cell Differentiation; Cell Proliferation; Cell Separation; Cell Size; Centrifugation, Density Gradient; Muscle Development; Muscle Fibers, Skeletal; Muscle, Skeletal; Povidone; Silicon Dioxide; Stem Cells; Sus scrofa
PubMed: 29523096
DOI: 10.1186/s12860-018-0156-1 -
The EMBO Journal Aug 2017Cyclin-dependent kinases (Cdks) are principal drivers of cell division and are an important therapeutic target to inhibit aberrant proliferation. Cdk enzymatic activity...
Cyclin-dependent kinases (Cdks) are principal drivers of cell division and are an important therapeutic target to inhibit aberrant proliferation. Cdk enzymatic activity is tightly controlled through cyclin interactions, posttranslational modifications, and binding of inhibitors such as the p27 tumor suppressor protein. Spy1/RINGO (Spy1) proteins bind and activate Cdk but are resistant to canonical regulatory mechanisms that establish cell-cycle checkpoints. Cancer cells exploit Spy1 to stimulate proliferation through inappropriate activation of Cdks, yet the mechanism is unknown. We have determined crystal structures of the Cdk2-Spy1 and p27-Cdk2-Spy1 complexes that reveal how Spy1 activates Cdk. We find that Spy1 confers structural changes to Cdk2 that obviate the requirement of Cdk activation loop phosphorylation. Spy1 lacks the cyclin-binding site that mediates p27 and substrate affinity, explaining why Cdk-Spy1 is poorly inhibited by p27 and lacks specificity for substrates with cyclin-docking sites. We identify mutations in Spy1 that ablate its ability to activate Cdk2 and to proliferate cells. Our structural description of Spy1 provides important mechanistic insights that may be utilized for targeting upregulated Spy1 in cancer.
Topics: Cell Cycle Proteins; Cyclin-Dependent Kinase 2; DNA Mutational Analysis; Gene Expression Regulation, Enzymologic; Phosphorylation; Proliferating Cell Nuclear Antigen; Protein Binding; Protein Processing, Post-Translational
PubMed: 28666995
DOI: 10.15252/embj.201796905 -
Development (Cambridge, England) Sep 2010During heart development, a subpopulation of cells in the heart field maintains cardiac potential over several days of development and forms the myocardium and smooth...
During heart development, a subpopulation of cells in the heart field maintains cardiac potential over several days of development and forms the myocardium and smooth muscle of the arterial pole. Using clonal and explant culture experiments, we show that these cells are a stem cell population that can differentiate into myocardium, smooth muscle and endothelial cells. The multipotent stem cells proliferate or differentiate into different cardiovascular cell fates through activation or inhibition of FGF and BMP signaling pathways. BMP promoted myocardial differentiation but not proliferation. FGF signaling promoted proliferation and induced smooth muscle differentiation, but inhibited myocardial differentiation. Blocking the Ras/Erk intracellular pathway promoted myocardial differentiation, while the PLCgamma and PI3K pathways regulated proliferation. In vivo, inhibition of both pathways resulted in predictable arterial pole defects. These studies suggest that myocardial differentiation of arterial pole progenitors requires BMP signaling combined with downregulation of the FGF/Ras/Erk pathway. The FGF pathway maintains the pool of proliferating stem cells and later promotes smooth muscle differentiation.
Topics: Animals; Arteries; Body Patterning; Bone Morphogenetic Protein 2; Cell Differentiation; Cell Lineage; Cell Proliferation; Chick Embryo; Fibroblast Growth Factor 8; Gene Expression Regulation, Developmental; Heart; MAP Kinase Signaling System; Muscle, Smooth; Myocardium; Quail; Stem Cells; Tissue Culture Techniques
PubMed: 20702561
DOI: 10.1242/dev.051565 -
Oncotarget Aug 2018High expression level of integrin α2β1 is a hallmark of prostate cancer stem cell like cells. The role of this collagen receptor is controversial since it is down...
High expression level of integrin α2β1 is a hallmark of prostate cancer stem cell like cells. The role of this collagen receptor is controversial since it is down regulated in poorly differentiated carcinomas, but concomitantly proposed to promote metastasis. Here, we show that docetaxel resistant DU145 prostate cancer cells express high levels of α2β1 and that α2β1 subpopulation of DU145 cells proliferates slower than the cells representing α2β1 subpopulation. To further study this initial observation we used Crispr/Cas9 technology to create an α2β1 negative DU145 cell line. Furthermore, we performed rescue experiment by transfecting α2 knockout cells with vector carrying α2 cDNA or with an empty vector for appropriate control. When these two cell lines were compared, α2β1 positive cells proliferated slower, were more resistant to docetaxel and also migrated more effectively on collagen and invaded faster through matrigel or collagen. Integrin α2β1 was demonstrated to be a positive regulator of p38 MAPK phosphorylation and a selective p38 inhibitor (SB203580) promoted proliferation and inhibited invasion. Effects of α2β1 integrin on the global gene expression pattern of DU145 cells in spheroid cultures were studied by RNA sequencing. Integrin α2β1 was shown to regulate several cancer progression related genes, most notably matrix metalloproteinase-1 (MMP-1), a recognized invasion promoting protein. To conclude, the fact that α2β1 decelerates cell proliferation may explain the dominance of α2β1 negative/low cells in primary sites of poorly differentiated carcinomas, while the critical role of α2β1 integrin in invasion stresses the importance of this adhesion receptor in cancer dissemination.
PubMed: 30197754
DOI: 10.18632/oncotarget.25945