Search results for "Cellular localization"
showing 10 items of 93 documents
Immunocytochemistry of M-cadherin in mature and regenerating rat muscle
1994
Background: Cadherins are transmembrane proteins mediating calcium-dependent cell–cell adhesion in a cell type-specific manner by means of homophilic binding. M(muscle)-cadherin is a recently detected member of the cadherin family. Methods: We have investigated the localization of M-cadherin innormal and aneurally regenerating skeletal muscle of rat by means of pre-embedding immunocytochemistry. The antibody was directed against the extra-cellular domain of M-cadherin. Results: Myoblasts and myotubes in regenerating muscles tended to be arranged in clusters enclosed by a common basal lamina. Satellite cells of mature muscle fibers were attached to the underlying fiber without separating bas…
Differences in the activity and distribution of peroxidases from three different portions of germinating Brassica oleracea seeds
2002
Peroxidase (POD, EC 1.11.1.7) activity, cellular localization and isozyme patterns were investigated in the seed integument, cotyledon and embryo axis of Brassica oleracea cv. Cappuccio during pregermination and seedling growth. Seeds started to germinate after 24 h of imbibition. POD activity was localized in the pigmented layer of the integument and in procambial strands of the cotyledon and embryo axis in the first 24 h of imbibition. It was localized in the integumental cells of palisade, pigmented and aleurone layers and in epidermal, meristematic, procambial cells and xylem elements of the root and hypocotyl after 48 h of imbibition. POD activity increased during germination and early…
Lafora disease fibroblasts exemplify the molecular interdependence between thioredoxin 1 and the proteasome in mammalian cells
2013
13 páginas, 8 figuras (que no aparecen en este documento, se pueden consultar en: http://www.sciencedirect.com/science/article/pii/S0891584913003274#ec0005)
Convergence of the target of rapamycin and the Snf1 protein kinase pathways in the regulation of the subcellular localization of Msn2, a transcriptio…
2002
The subcellular localization of Msn2, a transcriptional activator of STRE (stress response element)-regulated genes, is modulated by carbon source availability. In cells growing in glucose, Msn2 is located mainly in the cytosol, whereas in carbon source-starved cells, Msn2 is located largely inside the nucleus. However, in cells lacking Reg1 (the regulatory subunit of the Reg1/Glc7 protein phosphatase complex), the regulation of subcellular distribution is absent, Msn2 being constitutively present in the cytosol. The localization defect in these mutants is specific for carbon starvation stress, and it is because of the presence of an abnormally active Snf1 protein kinase that inhibits the n…
Novel Insights into the Cellular Localization and Regulation of the Autophagosomal Proteins LC3A, LC3B and LC3C
2020
Macroautophagy is a conserved degradative process for maintaining cellular homeostasis and plays a key role in aging and various human disorders. The microtubule-associated protein 1A/1B light chain 3B (MAP1LC3B or LC3B) is commonly analyzed as a key marker for autophagosomes and as a proxy for autophagic flux. Three paralogues of the LC3 gene exist in humans: LC3A, LC3B and LC3C. The molecular function, regulation and cellular localization of LC3A and LC3C have not been investigated frequently, even if a similar function to that described for LC3B appears likely. Here, we have selectively decapacitated LC3B by three separate strategies in primary human fibroblasts and analyzed the evoked e…
The Kelch protein NS1-BP interacts with alpha-enolase/MBP-1 and is involved in c-Myc gene transcriptional control
2007
Alpha-enolase is a key glycolytic enzyme that plays a functional role in several physiological processes depending on the cellular localization. The enzyme is mainly localized in the cytoplasm whereas an alternative translated form, named MBP-1, is predominantly nuclear. The MBP-1 protein has been characterized as a c-Myc promoter binding protein that negatively controls transcription. In the present study, we identified the kelch protein NS1-BP as one of the alpha-enolase/MBP-1 partners by using a yeast two-hybrid screening. Although NS1-BP has been originally described as a protein mainly localized in the nucleus, we provide evidence that NS1-BP also interacts with actin in human cells, a…
Immunohistological and immunoelectron microscopic identification of TNF alpha in normal human and murine epidermis.
1992
The presence, distribution and cellular localization of tumour necrosis factor-alpha (TNF alpha) were investigated in normal human and murine epidermis using immunohistological and immunoelectron microscopic methods with monoclonal and polyclonal antibodies. The immunostaining revealed an intercellular plasma membrane and cytoplasmic labelling of the epidermal keratinocytes, but no labelling of Langerhans cells, melanocytes and Merkel cells. Large amounts of TNF alpha were regularly found in the sebaceous glands. These findings demonstrate that epidermal keratinocytes and especially sebocytes produce and release TNF alpha and that this keratinocyte-derived cytokine may be important for the …
Yeast karyopherin Kap95 is required for cell cycle progression at Start
2010
Abstract Background The control of the subcellular localization of cell cycle regulators has emerged as a crucial mechanism in cell division regulation. The active transport of proteins between the nucleus and the cytoplasm is mediated by the transport receptors of the β-karyopherin family. In this work we characterized the terminal phenotype of a mutant strain in β-karyopherin Kap95, a component of the classical nuclear import pathway. Results When KAP95 was inactivated, most cells arrested at the G2/M phase of the cell cycle, which is in agreement with the results observed in mutants in the other components of this pathway. However, a number of cells accumulate at G1, suggesting a novel r…
Evidence for an intra- and extraplastidic pre-chorismate pathway.
1982
Pea plants grown under different conditions of cultivation, and eight different plant species with variegated leaves were used to study the intracellular localization of shikimate oxidoreductase (EC 1.1.1.25), the marker enzyme of the pre-chorismate pathway. The two series of experiments indicated an intra-and an extraplastidic compartimentalization of the enzyme, and both enzyme activities are regulated differentially. While the extraplastidic activity is permanently demonstrable, the intraplastidic activity is subject to the plants' developmental state and also depends on both illumination and fertilization.
Expression of protein kinase C gene family members is temporally and spatially regulated during neural development in vitro.
1998
We used primary cultures of rat hippocampal neurons and PCC7-Mz1 cells to correlate the expression of the protein kinase C (PKC) gene family with specific events during neural differentiation. Multipotent PCC7-Mz1 embryonic carcinoma stem cells develop into a tissue-like pattern of neuronal, fibroblast-like and astroglial cells by all-trans retinoic acid (RA) treatment. Western blot analyses demonstrate that PKCalpha, betaI, gamma, theta, mu, lambda, and zeta were constitutively expressed but the expression of PKCbetaII, delta, epsilon, and eta was up-regulated three days after addition of RA when cells mature morphologically. While the protein levels of the PKC isoforms betaII, delta and e…