scholarly journals Regulatory Potential of bHLH-Type Transcription Factors on the Road to Rubber Biosynthesis in Hevea brasiliensis

Plants ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 674
Author(s):  
Tomoko Yamaguchi ◽  
Yukio Kurihara ◽  
Yuko Makita ◽  
Emiko Okubo-Kurihara ◽  
Ami Kageyama ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Natural Rubber ◽  
Hevea Brasiliensis ◽  
Time Course ◽  
Molecular Mechanisms ◽  
Cultured Cells ◽  
Early Stage ◽  
Rubber Biosynthesis ◽  
On The Road

Natural rubber is the main component of latex obtained from laticifer cells of Hevea brasiliensis. For improving rubber yield, it is essential to understand the genetic molecular mechanisms responsible for laticifer differentiation and rubber biosynthesis. Jasmonate enhances both secondary laticifer differentiation and rubber biosynthesis. Here, we carried out time-course RNA-seq analysis in suspension-cultured cells treated with methyljasmonic acid (MeJA) to characterize the gene expression profile. Gene Ontology (GO) analysis showed that the term “cell differentiation” was enriched in upregulated genes at 24 h after treatment, but inversely, the term was enriched in downregulated genes at 5 days, indicating that MeJA could induce cell differentiation at an early stage of the response. Jasmonate signaling is activated by MYC2, a basic helix–loop–helix (bHLH)-type transcription factor (TF). The aim of this work was to find any links between transcriptomic changes after MeJA application and regulation by TFs. Using an in vitro binding assay, we traced candidate genes throughout the whole genome that were targeted by four bHLH TFs: Hb_MYC2-1, Hb_MYC2-2, Hb_bHLH1, and Hb_bHLH2. The latter two are highly expressed in laticifer cells. Their physical binding sites were found in the promoter regions of a variety of other TF genes, which are differentially expressed upon MeJA exposure, and rubber biogenesis-related genes including SRPP1 and REF3. These studies suggest the possibilities that Hb_MYC2-1 and Hb_MYC2-2 regulate cell differentiation and that Hb_bHLH1 and Hb_bHLH2 promote rubber biosynthesis. We expect that our findings will help to increase natural rubber yield through genetic control in the future.

scholarly journals Cellular maturation in human preleukemia

Blood ◽  
1978 ◽  
Vol 52 (2) ◽  
pp. 355-361
Author(s):  
HP Koeffler ◽  
DW Golde
Keyword(s):  
Bone Marrow ◽  
Cell Differentiation ◽  
Liquid Culture ◽  
Cultured Cells ◽  
Bone Marrow Cells ◽  
Myelogenous Leukemia ◽  
Bone Marrow Cultures ◽  
Acute Myelogenous ◽  
Marrow Cultures

Bone marrow cells from three preleukemic patients with prominent marrow karyotypic abnormalities were studied in liquid culture to determine if the neoplastic clones were capable of maturation. Parallel cytogenetic and cytologic studies were performed in sequentially harvested bone marrow cultures. Maturation, albeit delayed, occurred in cultures from all three patients. By 14 days of culture in vitro, morphologic, cytochemical, and functional evidence of maturation was observed in about 70% of the cells. By day 21, 85% of the cells were mature by these criteria. All but 2 of 249 metaphases from the cultured cells contained the cytogenetic abnormality of the neoplastic clone. We conclude that some preleukemic cells identified by a chromosomal abnormality can mature in vitro. Preleukemia may be viewed as a syndrome of “early leukemia” in which the neoplastic clone is established and manifested functionally as ineffective hematopoiesis. Hematopoietic cell differentiation becomes progressively abnormal with termination in the nearly complete maturational block characteristic of acute myelogenous leukemia.

scholarly journals Human Endometrial Stromal Cell Differentiation is Stimulated by PPARβ/δ Activation: New Targets for Infertility?

2020 ◽  
Vol 105 (9) ◽  
pp. 2983-2995 ◽  
Author(s):  
Jie Yu ◽  
Sarah L Berga ◽  
Wei Zou ◽  
Augustine Rajakumar ◽  
Mingfei Man ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Growth Factor ◽  
Connexin 43 ◽  
Time Course ◽  
Estrogen Receptor Α ◽  
Peroxisome Proliferator ◽  
Endometrial Stromal Cells ◽  
Peroxisome Proliferator Activated Receptor ◽  
Therapeutic Benefits

Abstract Context Implantation is a reproductive bottleneck in women, regulated by fluctuations in ovarian steroid hormone concentrations. However, other nuclear receptor ligands are modifiers of endometrial differentiation leading to successful pregnancy. In the present study we analyzed the effects of peroxisome-proliferator-activated receptor β/δ (PPARβ/δ) activation on established cellular biomarkers of human endometrial differentiation (decidualization). Objective The objective of this work is to test the effects of PPARβ/δ ligation on human endometrial cell differentiation. Design Isolated primary human endometrial stromal cells (ESCs) were treated with synthetic (GW0742) or natural (all trans-retinoic acid, RA) ligands of PPARβ/δ, and also with receptor antagonists (GSK0660, PT-S58, and ST247) in the absence or presence of decidualizing hormones (10 nM estradiol, 100 nM progesterone, and 0.5 mM dibutyryl cAMP [3′,5′-cyclic adenosine 5′-monophosphate]). In some cases interleukin (IL)-1β was used as an inflammatory stimulus. Time course and dose-response relationships were evaluated to determine effects on panels of well characterized in vitro biomarkers of decidualization. Results PPARβ/δ, along with estrogen receptor α (ERα) and PR-A and PR-B, were expressed in human endometrial tissue and isolated ESCs. GW0742 treatment enhanced hormone-mediated ESC decidualization in vitro as manifested by upregulation of prolactin, insulin-like growth factor-binding protein 1, IL-11, and vascular endothelial growth factor (VEGF) secretion and also increased expression of ERα, PR-A and PR-B, and connexin 43 (Cx43). RA treatment also increased VEGF, ERα, PR-A, and PR-B and an active, nonphosphorylated isoform of Cx43. IL-1β and PPARβ/δ antagonists inhibited biomarkers of endometrial differentiation. Conclusion Ligands that activate PPARβ/δ augment the in vitro expression of biomarkers of ESC decidualization. By contrast, PPARβ/δ antagonists impaired decidualization markers. Drugs activating these receptors may have therapeutic benefits for embryonic implantation.

scholarly journals Molecular Mechanisms of Anti-Melanogenic Gedunin Derived from Neem Tree (Azadirachta indica) Using B16F10 Mouse Melanoma Cells and Early-Stage Zebrafish

Plants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 330
Author(s):  
Hwang-Ju Jeon ◽  
Kyeongnam Kim ◽  
Chaeeun Kim ◽  
Myoung-Jin Kim ◽  
Tae-Oh Kim ◽  
...  
Keyword(s):  
Skin Color ◽  
Molecular Mechanisms ◽  
Early Stage ◽  
Melanoma Cells ◽  
Ultraviolet Rays ◽  
Melanin Production ◽  
Zebrafish Model ◽  
Mouse Melanoma

Melanogenesis represents a series of processes that produce melanin, a protective skin pigment (against ultraviolet rays), and determines human skin color. Chemicals reducing melanin production have always been in demand in the cosmetic market because of skincare interests, such as whitening. The main mechanism for inhibiting melanin production is the inhibition of tyrosinase (TYR), a key enzyme for melanogenesis. Here, we evaluated gedunin (Ged), a representative limonoid, for its anti-melanogenesis action. Melanin production in vitro was stimulated by alpha-melanocyte stimulating hormone (α-MSH) in B16F10 mouse melanoma cells. Ged reduced α-MSH-stimulated melanin production, inhibiting TYR activity and protein amount. We confirmed this result in vivo in a zebrafish model for melanogenesis. There was no sign of toxicity and malformation of zebrafish embryos during development in all treated concentrations. Ged reduced the number of produced zebrafish embryo pigment dots and melanin contents of embryos. The highly active concentration of Ged (100 µM) was much lower than the positive control, kojic acid (8 mM). Hence, Ged could be a fascinating candidate for anti-melanogenesis reagents.

scholarly journals Real-Time Analysis of Endogenous Wnt Signalling in 3D Mesenchymal Stromal Cells

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Fatima Saleh ◽  
Alice Carstairs ◽  
S. Leah Etheridge ◽  
Paul Genever
Keyword(s):  
Time Course ◽  
Molecular Mechanisms ◽  
Adipogenic Differentiation ◽  
Wnt Signalling ◽  
Egfp Expression ◽  
Culture Techniques ◽  
Real Time Analysis ◽  
Pathway Activation

Wnt signalling has been implicated in the regulation of stem cell self-renewal and differentiation; however, the majority of in vitro studies are carried out using monolayer 2D culture techniques. Here, we used mesenchymal stromal cell (MSC) EGFP reporter lines responsive to Wnt pathway activation in a 3D spheroid culture system to mimic better the in vivo environment. Endogenous Wnt signalling was then investigated under basal conditions and when MSCs were induced to undergo osteogenic and adipogenic differentiation. Interestingly, endogenous Wnt signalling was only active during 3D differentiation whereas 2D cultures showed no EGFP expression throughout an extended differentiation time-course. Furthermore, exogenous Wnt signalling in 3D adipogenic conditions inhibited differentiation compared to unstimulated controls. In addition, suppressing Wnt signalling by Dkk-1 restored and facilitated adipogenic differentiation in MSC spheroids. Our findings indicate that endogenous Wnt signalling is active and can be tracked in 3D MSC cultures where it may act as a molecular switch in adipogenesis. The identification of the signalling pathways that regulate MSCs in a 3D in vivo-like environment will advance our understanding of the molecular mechanisms that control MSC fate.

scholarly journals Microtubule-organizing centers abnormal in number, structure, and nucleating activity in x-irradiated mammalian cells.

1983 ◽  
Vol 96 (3) ◽  
pp. 776-782 ◽  
Author(s):  
C Sato ◽  
R Kuriyama ◽  
K Nishizawa
Keyword(s):  
Mammalian Cells ◽  
Time Course ◽  
Cultured Cells ◽  
Mitotic Cell ◽  
Amorphous Structure ◽  
Dark Field ◽  
Microtubule Depolymerization ◽  
Microtubule Organizing Centers ◽  
Mitotic Cells

Microtubule-organizing centers (MTOCs) in x-irradiated cells were visualized by immunofluorescence using antibody against tubulin. From two to ten reassembly sites of microtubules appeared after microtubule depolymerization at low temperature in an irradiated mitotic cell, in contrast to nonirradiated mitotic cells, which predominantly show 2 MTOCs. A time-course examination of MTOCs in synchronously cultured cells revealed that the multiple MTOCs appeared not immediately after irradiation but at the time of mitosis. Those multiple MTOCs formed at mitosis were inherited by the daughter cells in the next generation. The structure and capacity of the centrosomes to nucleate microtubules in vitro were then examined by electron microscopy of whole-mount preparations as well as by dark-field microscopy. About 70-80% of the centrosomes derived from nonirradiated cells were composed of a pair of centrioles and pericentriolar material, which initiated greater than 100 microtubules. The fraction of fully active complete centrosomes decreased with time of incubation after irradiation. These were replaced by disintegrated centrosomal components such as dissociated centrioles and pericentriolar cloud, a nucleating site with a single centriole, or only an amorphous structure of pericentriolar cloud. Assembly of less than 20 microtubules onto the amorphous cloud without centrioles was seen in 54% of the initiating sites in mitotic cells 2 d after irradiation. These results suggest that x-irradiation causes disintegration of centrosomes at mitosis when the structural and functional reorganization of centrosomes is believed to occur.

scholarly journals qPCR analysis of mesenchymal stem cell marker expression during the long-term culture of canine adipocyte derived stem cells

2020 ◽  
Vol 8 (4) ◽  
pp. 139-145
Author(s):  
Rut Bryl ◽  
Claudia Dompe ◽  
Maurycy Jankowski ◽  
Katarzyna Stefańska ◽  
Afsaneh Golkar Narenji ◽  
...  
Keyword(s):  
Stem Cells ◽  
Molecular Mechanisms ◽  
Cultured Cells ◽  
Stem Cell Marker ◽  
Pcr Analysis ◽  
Marker Genes ◽  
Long Term Culture ◽  
Marker Expression

AbstractDue to its availability and accessibility, adipose tissue has been the subject of various studies in many different medical fields and is believed to be a useful source of stem cells. The ability of ASCs to differentiate towards different cell lineages, with possibility of directing this differentiation, increases their possible clinical applications, and they have been widely employed in multiple therapies and treatment of different pathologies. However, a deeper understanding of the molecular mechanisms underlying the ASCs osteoblastic and chondrocyte differentiation may lead to novel applications treating a multitude of different bone-related diseases through techniques more likely meeting worldwide consensus. In this study, the RT-qPCR method was used to determine the changes in expression of ASC specific markers (CD105, CD73, CD14, CD34, CD90 and CD45) before and after long-term (14-day) in vitro cultures. To confirm the identity of the investigated cells, flow cytometry was used to evaluate the presence of positive (CD44, CD90) and negative (CD45, CD34) ASC markers. Overall, the results of the PCR analysis showed a significant change in expression of most of the marker genes, indicating significant changes in the cultured cells caused by their long-term culture, potentially altering their original stem-like characteristics.Running title: ASC marker expression during long-term in vitro culture

scholarly journals Aggregation of Aβ40/42 chains in the presence of cyclic neuropeptides investigated by molecular dynamics simulations

2021 ◽  
Vol 17 (3) ◽  
pp. e1008771
Author(s):  
Min Wu ◽  
Lyudmyla Dorosh ◽  
Gerold Schmitt-Ulms ◽  
Holger Wille ◽  
Maria Stepanova
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Cyclic Peptides ◽  
Molecular Mechanisms ◽  
Surface Effect ◽  
Early Stage ◽  
Aβ Peptides ◽  
Hydrophobic Residues ◽  
Dynamics Simulations

Alzheimer’s disease is associated with the formation of toxic aggregates of amyloid beta (Aβ) peptides. Despite tremendous efforts, our understanding of the molecular mechanisms of aggregation, as well as cofactors that might influence it, remains incomplete. The small cyclic neuropeptide somatostatin-14 (SST14) was recently found to be the most selectively enriched protein in human frontal lobe extracts that binds Aβ42 aggregates. Furthermore, SST14’s presence was also found to promote the formation of toxic Aβ42 oligomers in vitro. In order to elucidate how SST14 influences the onset of Aβ oligomerization, we performed all-atom molecular dynamics simulations of model mixtures of Aβ42 or Aβ40 peptides with SST14 molecules and analyzed the structure and dynamics of early-stage aggregates. For comparison we also analyzed the aggregation of Aβ42 in the presence of arginine vasopressin (AVP), a different cyclic neuropeptide. We observed the formation of self-assembled aggregates containing the Aβ chains and small cyclic peptides in all mixtures of Aβ42–SST14, Aβ42–AVP, and Aβ40–SST14. The Aβ42–SST14 mixtures were found to develop compact, dynamically stable, but small aggregates with the highest exposure of hydrophobic residues to the solvent. Differences in the morphology and dynamics of aggregates that comprise SST14 or AVP appear to reflect distinct (1) regions of the Aβ chains they interact with; (2) the propensities to engage in hydrogen bonds with Aβ peptides; and (3) solvent exposures of hydrophilic and hydrophobic groups. The presence of SST14 was found to impede aggregation in the Aβ42–SST14 system despite a high hydrophobicity, producing a stronger “sticky surface” effect in the aggregates at the onset of Aβ42–SST14 oligomerization.

Mechanical forces and their second messengers in stimulating cell growth in vitro

1992 ◽  
Vol 262 (3) ◽  
pp. R350-R355 ◽  
Author(s):  
H. H. Vandenburgh
Keyword(s):  
Cell Growth ◽  
Molecular Mechanisms ◽  
Cultured Cells ◽  
Second Messengers ◽  
Second Messenger ◽  
Model Systems ◽  
Mechanical Forces ◽  
Unicellular Organisms ◽  
Multicellular Organisms

Mechanical forces play an important role in modulating the growth of a number of different tissues including skeletal muscle, smooth muscle, cardiac muscle, bone, endothelium, epithelium, and lung. As interest increases in the molecular mechanisms by which mechanical forces are transduced into growth alterations, model systems are being developed to study these processes in tissue culture. This paper reviews the current methods available for mechanically stimulating tissue cultured cells. It then outlines some of the putative “mechanogenic” second messengers involved in altering cell growth. Not surprisingly, many mechanogenic second messengers are the same as those involved in growth factor-induced cell growth. It is hypothesized that from an evolutionary standpoint, some second messenger systems may have initially evolved for unicellular organisms to respond to physical forces such as gravity and mechanical perturbation in their environment. As multicellular organisms came into existence, they appropriated these mechanogenic second messenger cascades for cellular regulation by growth factors.

Transcriptional profiling of in vitro smooth muscle cell differentiation identifies specific patterns of gene and pathway activation

2004 ◽  
Vol 19 (3) ◽  
pp. 292-302 ◽  
Author(s):  
Joshua M. Spin ◽  
Shriram Nallamshetty ◽  
Raymond Tabibiazar ◽  
Euan A. Ashley ◽  
Jennifer Y. King ◽  
...  
Keyword(s):  
Gene Expression ◽  
Smooth Muscle ◽  
Smooth Muscle Cell ◽  
Muscle Cell ◽  
Large Scale ◽  
Time Course ◽  
Molecular Mechanisms ◽  
Transcriptional Profiling ◽  
Temporal Trends

Mesodermal and epidermal precursor cells undergo phenotypic changes during differentiation to the smooth muscle cell (SMC) lineage that are relevant to pathophysiological processes in the adult. Molecular mechanisms that underlie lineage determination and terminal differentiation of this cell type have received much attention, but the genetic program that regulates these processes has not been fully defined. Study of SMC differentiation has been facilitated by development of the P19-derived A404 embryonal cell line, which differentiates toward this lineage in the presence of retinoic acid and allows selection for cells adopting a SMC fate through a differentiation-specific drug marker. We sought to define global alterations in gene expression by studying A404 cells during SMC differentiation with oligonucleotide microarray transcriptional profiling. Using an in situ 60-mer array platform with more than 20,000 mouse genes derived from the National Institute on Aging clone set, we identified 2,739 genes that were significantly upregulated after differentiation was completed (false-detection ratio <1). These genes encode numerous markers known to characterize differentiated SMC, as well as many unknown factors. We further characterized the sequential patterns of gene expression during the differentiation time course, particularly for known transcription factor families, providing new insights into the regulation of the differentiation process. Changes in genes associated with specific biological ontology-based pathways were evaluated, and temporal trends were identified for functional pathways. In addition to confirming the utility of the A404 model, our data provide a large-scale perspective of gene regulation during SMC differentiation.

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