Search results for "Cell division"
showing 10 items of 457 documents
The targeted overexpression of SlCDF4 in the fruit enhances tomato size and yield involving gibberellin signalling
2020
AbstractTomato is one of the most widely cultivated vegetable crops and a model for studying fruit biology. Although several genes involved in the traits of fruit quality, development and size have been identified, little is known about the regulatory genes controlling its growth. In this study, we characterized the role of the tomato SlCDF4 gene in fruit development, a cycling DOF-type transcription factor highly expressed in fruits. The targeted overexpression of SlCDF4 gene in the fruit induced an increased yield based on a higher amount of both water and dry matter accumulated in the fruits. Accordingly, transcript levels of genes involved in water transport and cell division and expans…
Gibberellin reactivates and maintains ovary-wall cell division causing fruit set in parthenocarpic Citrus species
2016
[EN] Citrus is a wide genus in which most of the cultivated species and cultivars are natural parthenocarpic mutants or hybrids (i.e. orange, mandarin, tangerine, grapefruit). The autonomous increase in GA(1) ovary concentration during anthesis was suggested as being the stimulus responsible for parthenocarpy in Citrus regardless of the species. To determine the exact GA-role in parthenocarpic fruit set, the following hypothesis was tested: GA triggers and maintains cell division in ovary walls causing fruit set. Obligate and facultative parthenocarpic Citrus species were used as a model system because obligate parthenocarpic Citrus sp (i.e. Citrus unshiu) have higher GA levels and better n…
Calcium homeostasis in plant cell nuclei
2009
International audience; In plant cells, calcium-based signaling pathways are involved in a large array of biological processes, including cell division, polarity, growth, development and adaptation to changing biotic and abiotic environmental conditions. Free calcium changes are known to proceed in a nonstereotypical manner and produce a specific signature, which mirrors the nature, strength and frequency of a stimulus. The temporal aspects of calcium signatures are well documented, but their vectorial aspects also have a profound influence on biological output. Here, we will focus on the regulation of calcium homeostasis in the nucleus. We will discuss data and present hypotheses suggestin…
Fruit Growth Stage Transitions in Two Mango Cultivars Grown in a Mediterranean Environment
2021
Studying mango (Mangifera 
Molecular, Biological and Structural Features of VL CDR-1 Rb44 Peptide, Which Targets the Microtubule Network in Melanoma Cells
2019
Microtubules are important drug targets in tumor cells, owing to their role in supporting and determining the cell shape, organelle movement and cell division. The complementarity-determining regions (CDRs) of immunoglobulins have been reported to be a source of anti-tumor peptide sequences, independently of the original antibody specificity for a given antigen. We found that, the anti-Lewis B mAb light-chain CDR1 synthetic peptide Rb44, interacted with microtubules and induced depolymerization, with subsequent degradation of actin filaments, leading to depolarization of mitochondrial membrane-potential, increase of ROS, cell cycle arrest at G2/M, cleavage of caspase-9, caspase-3 and PARP, …
Lack of a peroxiredoxin suppresses the lethality of cells devoid of electron donors by channelling electrons to oxidized ribonucleotide reductase
2017
The thioredoxin and glutaredoxin pathways are responsible of recycling several enzymes which undergo intramolecular disulfide bond formation as part of their catalytic cycles such as the peroxide scavengers peroxiredoxins or the enzyme ribonucleotide reductase (RNR). RNR, the rate-limiting enzyme of deoxyribonucleotide synthesis, is an essential enzyme relying on these electron flow cascades for recycling. RNR is tightly regulated in a cell cycle-dependent manner at different levels, but little is known about the participation of electron donors in such regulation. Here, we show that cytosolic thioredoxins Trx1 and Trx3 are the primary electron donors for RNR in fission yeast. Unexpectedly,…
Increasing Neural Stem Cell Division Asymmetry and Quiescence Are Predicted to Contribute to the Age-Related Decline in Neurogenesis.
2018
Summary: Adult murine neural stem cells (NSCs) generate neurons in drastically declining numbers with age. How cellular dynamics sustain neurogenesis and how alterations with age may result in this decline are unresolved issues. We therefore clonally traced NSC lineages using confetti reporters in young and middle-aged adult mice. To understand the underlying mechanisms, we derived mathematical models that explain observed clonal cell type abundances. The best models consistently show self-renewal of transit-amplifying progenitors and rapid neuroblast cell cycle exit. In middle-aged mice, we identified an increased probability of asymmetric stem cell divisions at the expense of symmetric di…
The Fate Choice Between Effector and Memory T Cell Lineages: Asymmetry, Signal Integration, and Feedback to Create Bistability
2018
Abstract CD8+ T cells clear primary infections with intracellular pathogens and provide long-term immunity against reinfection. Two different types of CD8+ T cells are responsible for these functions: short-lived effector T cells and memory T cells. The cellular relationship between these two types of CD8+ T cells has been subject to much investigation. Both cell types can derive from a single naive CD8+ T cell precursor. Their generation requires a fate choice early during a T cell response. As a result, two populations of T cells emerge. One of these consists of terminally differentiated short-lived effector T cells. The other contains cells able to develop into long-lived memory T cells.…
Long Term Culture of the A549 Cancer Cell Line Promotes Multilamellar Body Formation and Differentiation towards an Alveolar Type II Pneumocyte Pheno…
2016
Pulmonary research requires models that represent the physiology of alveolar epithelium but concerns with reproducibility, consistency and the technical and ethical challenges of using primary or stem cells has resulted in widespread use of continuous cancer or other immortalized cell lines. The A549 'alveolar' cell line has been available for over four decades but there is an inconsistent view as to its suitability as an appropriate model for primary alveolar type II (ATII) cells. Since most work with A549 cells involves short term culture of proliferating cells, we postulated that culture conditions that reduced proliferation of the cancer cells would promote a more differentiated ATII ce…
GW-Bodies and P-Bodies Constitute Two Separate Pools of Sequestered Non-Translating RNAs
2015
Non-translating RNAs that have undergone active translational repression are culled from the cytoplasm into P-bodies for decapping-dependent decay or for sequestration. Organisms that use microRNA-mediated RNA silencing have an additional pathway to remove RNAs from active translation. Consequently, proteins that govern microRNA-mediated silencing, such as GW182/Gw and AGO1, are often associated with the P-bodies of higher eukaryotic organisms. Due to the presence of Gw, these structures have been referred to as GW-bodies. However, several reports have indicated that GW-bodies have different dynamics to P-bodies. Here, we use live imaging to examine GW-body and P-body dynamics in the early …