scholarly journals Cellular Localization of Isoprenoid Biosynthetic Enzymes inMarchantia polymorpha. Uncovering a New Role of Oil Bodies

2000 ◽  
Vol 124 (3) ◽  
pp. 971-978 ◽  
Author(s):  
Claude Suire ◽  
Florence Bouvier ◽  
Ralph A. Backhaus ◽  
Dominique Bégu ◽  
Marc Bonneu ◽  
...  
Keyword(s):  
Cellular Localization ◽  
Biosynthetic Enzymes ◽  
Oil Bodies

TRiC-P5, a novel TCP1-related protein, is localized in the cytoplasm and in the nuclear matrix

1994 ◽  
Vol 107 (10) ◽  
pp. 2851-2859
Author(s):  
E.C. Joly ◽  
E. Tremblay ◽  
R.M. Tanguay ◽  
Y. Wu ◽  
V. Bibor-Hardy
Keyword(s):  
Nuclear Matrix ◽  
Cellular Localization ◽  
Cell Fractionation ◽  
Cellular Functions ◽  
Raji Cells ◽  
T Complex ◽  
Ring Complex ◽  
Filament Network ◽  
Novel Protein

We have recently reported the cloning of a novel protein, TRiC-P5, with significant homology with protein 1 of the t-complex (TCP1). In the present study, the cellular localization of TRiC-P5 in Raji cells has been determined using an antiserum raised against a 18.5 kDa fusion protein. Results from cell fractionation and immunoblot studies indicate that TRiC-P5 is mainly localized in the cytoplasm. In addition, a significant part of TRiC-P5 is also found in the nucleus where it is attached to the nuclear matrix, a complex filament network involved in essential cellular functions such as DNA replication, and RNA transcription and maturation. Immunofluorescence experiments using the anti-TRiC-P5 antibodies confirm these results. We also provide evidence that, in the cytoplasm, TRiC-P5 is part of a large protein complex, most probably the TCP1-ring complex (TRiC), a hetero-oligomeric ring complex that plays a role of molecular chaperone in the folding of actin and tubulin.

scholarly journals A Pro-Tumorigenic Effect of Heparanase 2 (Hpa2) in Thyroid Carcinoma Involves Its Localization to the Nuclear Membrane

2021 ◽  
Vol 11 ◽  
Author(s):  
Itai Margulis ◽  
Inna Naroditsky ◽  
Miriam Gross-Cohen ◽  
Neta Ilan ◽  
Israel Vlodavsky ◽  
...  
Keyword(s):  
Thyroid Carcinoma ◽  
Lymph Nodes ◽  
Nuclear Membrane ◽  
Tumor Metastasis ◽  
Cellular Localization ◽  
Thyroid Tissue ◽  
Clinicopathological Parameters ◽  
Regional Lymph Nodes ◽  
Normal Thyroid

Activity of the endo-beta-glucuronidase heparanase, capable of cleaving heparan sulfate (HS), is most often elevated in many types of tumors, associating with increased tumor metastasis and decreased patients’ survival. Heparanase is therefore considered to be a valid drug target, and heparanase inhibitors are being evaluated clinically in cancer patients. Heparanase 2 (Hpa2) is a close homolog of heparanase that gained very little attention, likely because it lacks HS-degrading activity typical of heparanase. The role of Hpa2 in cancer was not examined in detail. In head and neck cancer, high levels of Hpa2 are associated with decreased tumor cell dissemination to regional lymph nodes and prolonged patients’ survival, suggesting that Hpa2 functions to attenuate tumor growth. Here, we examined the role of Hpa2 in normal thyroid tissue and in benign thyroid tumor, non-metastatic, and metastatic papillary thyroid carcinoma (PTC) utilizing immunostaining in correlation with clinicopathological parameters. Interestingly, we found that Hpa2 staining intensity does not significantly change in the transition from normal thyroid gland to benign, non-metastatic, or metastatic thyroid carcinoma. Remarkably, we observed that in some biopsies, Hpa2 is accumulating on the membrane (envelop) of the nucleus and termed this cellular localization NM (nuclear membrane). Notably, NM localization of Hpa2 occurred primarily in metastatic PTC and was associated with an increased number of positive (metastatic) lymph nodes collected at surgery. These results describe for the first time unrecognized localization of Hpa2 to the nuclear membrane, implying that in PTC, Hpa2 functions to promote tumor metastasis.

scholarly journals RAC1 Takes the Lead in Solid Tumors

Cells ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 382 ◽  
Author(s):  
Pradip De ◽  
Jennifer Carlson Aske ◽  
Nandini Dey
Keyword(s):  
Drug Resistance ◽  
Embryonic Development ◽  
Solid Tumors ◽  
Tumor Cells ◽  
Cellular Localization ◽  
Regulatory Mechanisms ◽  
Cellular Functions ◽  
Patterns Of Distribution ◽  
Background Data

Three GTPases, RAC, RHO, and Cdc42, play essential roles in coordinating many cellular functions during embryonic development, both in healthy cells and in disease conditions like cancers. We have presented patterns of distribution of the frequency of RAC1-alteration(s) in cancers as obtained from cBioPortal. With this background data, we have interrogated the various functions of RAC1 in tumors, including proliferation, metastasis-associated phenotypes, and drug-resistance with a special emphasis on solid tumors in adults. We have reviewed the activation and regulation of RAC1 functions on the basis of its sub-cellular localization in tumor cells. Our review focuses on the role of RAC1 in cancers and summarizes the regulatory mechanisms, inhibitory efficacy, and the anticancer potential of RAC1-PAK targeting agents.

Role of polyamines in differentiation of 3T3-L1 fibroblasts into adipocytes

1984 ◽  
Vol 246 (3) ◽  
pp. C293-C300 ◽  
Author(s):  
B. G. Erwin ◽  
D. R. Bethell ◽  
A. E. Pegg
Keyword(s):  
Ornithine Decarboxylase ◽  
Biosynthetic Enzymes ◽  
Irreversible Inhibitor ◽  
Inhibition Of Differentiation ◽  
Increased Activity ◽  
Adipose Cells ◽  
Partial Reversal

The role of polyamines in the differentiation of 3T3-L1 fibroblasts into adipose cells was studied. This conversion was blocked by the addition of alpha-difluoromethylornithine, an enzyme-activated irreversible inhibitor of ornithine decarboxylase, which prevented a rise in spermidine content in the differentiating cells. The inhibition of differentiation could be overcome completely by the provision of exogenous putrescine, spermidine, or spermine. Partial reversal could be produced by exposure to nonphysiological homologues of the natural polyamines such as 1,3-diaminopropane, 1,5-diaminopentane, and sym-norspermine. Reversal of the inhibition of differentiation by exogenous polyamines required a period of exposure to the amines, indicating that the lack of differentiation is not due simply to an obligatory role for polyamines in the biosynthesis of lipids. These results indicate that spermidine is required for the differentiation, but spermidine alone was not able to replace insulin and 1-methyl-3-isobutylxanthine in stimulating conversion to adipocytes. Therefore spermidine appears to be necessary but not sufficient for differentiation to occur. Finally, the elevation of spermidine content that occurs during the conversion of fibroblasts to adipocytes did not correlate with an increased activity of the polyamine biosynthetic enzymes. This implies that the increase must be regulated by changes in the rate of degradation or excretion of the polyamines.

Role of the sub-cellular localization of RasGAP fragment N2 for its ability to sensitize cancer cells to genotoxin-induced apoptosis

2009 ◽  
Vol 315 (12) ◽  
pp. 2081-2091 ◽  
Author(s):  
Alessandro Annibaldi ◽  
David Michod ◽  
Linda Vanetta ◽  
Steeve Cruchet ◽  
Pascal Nicod ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Cellular Localization ◽  
Induced Apoptosis

scholarly journals Peroxisome extensions deliver the Arabidopsis SDP1 lipase to oil bodies

2015 ◽  
Vol 112 (13) ◽  
pp. 4158-4163 ◽  
Author(s):  
Nelcy Thazar-Poulot ◽  
Martine Miquel ◽  
Isabelle Fobis-Loisy ◽  
Thierry Gaude
Keyword(s):  
Protein Trafficking ◽  
Protein Transport ◽  
Energy Resource ◽  
High Energy ◽  
Eukaryotic Cells ◽  
Oil Bodies ◽  
Energy Demands ◽  
Lipid Store ◽  
Lipid Stores

Lipid droplets/oil bodies (OBs) are lipid-storage organelles that play a crucial role as an energy resource in a variety of eukaryotic cells. Lipid stores are mobilized in the case of food deprivation or high energy demands—for example, during certain developmental processes in animals and plants. OB degradation is achieved by lipases that hydrolyze triacylglycerols (TAGs) into free fatty acids and glycerol. In the model plant Arabidopsis thaliana, Sugar-Dependent 1 (SDP1) was identified as the major TAG lipase involved in lipid reserve mobilization during seedling establishment. Although the enzymatic activity of SDP1 is associated with the membrane of OBs, its targeting to the OB surface remains uncharacterized. Here we demonstrate that the core retromer, a complex involved in protein trafficking, participates in OB biogenesis, lipid store degradation, and SDP1 localization to OBs. We also report an as-yet-undescribed mechanism for lipase transport in eukaryotic cells, with SDP1 being first localized to the peroxisome membrane at early stages of seedling growth and then possibly moving to the OB surface through peroxisome tubulations. Finally, we show that the timely transfer of SDP1 to the OB membrane requires a functional core retromer. In addition to revealing previously unidentified functions of the retromer complex in plant cells, our work provides unanticipated evidence for the role of peroxisome dynamics in interorganelle communication and protein transport.

scholarly journals Cellular Localization and Functional Role of Phosphatidylcholine-Specific Phospholipase C in NK Cells

2001 ◽  
Vol 167 (5) ◽  
pp. 2642-2650 ◽  
Author(s):  
Carlo Ramoni ◽  
Francesca Spadaro ◽  
Michela Menegon ◽  
Franca Podo
Keyword(s):  
Nk Cells ◽  
Phospholipase C ◽  
Functional Role ◽  
Cellular Localization

Cellular distributions of creatine kinase in branchia of euryhaline tilapia (Oreochromis mossambicus)

2003 ◽  
Vol 284 (1) ◽  
pp. C233-C241 ◽  
Author(s):  
Li-Yih Lin ◽  
Chia-Chang Chiang ◽  
Hong-Yi Gong ◽  
Ching-Yi Cheng ◽  
Pung-Pung Hwang ◽  
...  
Keyword(s):  
Creatine Kinase ◽  
Cellular Localization ◽  
Potential Role ◽  
Oreochromis Mossambicus ◽  
Staining Intensity ◽  
Muscle Type ◽  
Environmental Fluctuation ◽  
High Association ◽  
Salinity Changes

Although euryhaline teleosts can adapt to environmental fluctuation of salinity, their energy source for responding to changes in salinity and osmolarity remains unclear. This study examines the cellular localization of creatine kinase (CK) expression in branchia of tilapia ( Oreochromis mossambicus). Western blot analysis of muscle-type CK (MM form) revealed a high association with salinity changes, but BB and MB forms of CK in the gills of fish adapted to seawater did not change. With the use of immunocytochemistry, three CK isoforms (MM, MB, and BB) were localized in mitochondria-rich (MR) cells and other epithelial cells of tilapia gills. In addition, staining intensity of MM-form CK in MR cells increased after seawater transfer, whereas BB and MB forms did not significantly change. To our knowledge, this work presents the first evidence of CK expression in MR cells of tilapia gills, highlighting the potential role of CK in providing energy for ion transport.

scholarly journals Identification of Type VI Collagen Synthesizing Cells in Human Diabetic Glomerulosclerosis Using Renal Biopsy Sections

1997 ◽  
Vol 15 (3) ◽  
pp. 175-181 ◽  
Author(s):  
Mohammed Shawkat Razzaque ◽  
Takehiko Koji ◽  
Takashi Harada ◽  
Takashi Taguchi
Keyword(s):  
Renal Biopsy ◽  
Cellular Localization ◽  
Oligonucleotide Probes ◽  
Diabetic Glomerulosclerosis ◽  
Type Vi Collagen ◽  
Cellular Origin ◽  
Collagen Mrna ◽  
Nodular Lesions

Although the role of extracellular matrices in the development of glomerulosclerosis has been discussed widely, the cellular origin of type VI collagen in diabetic nephropathy (DN) has remained relatively unexplored. This study reports the distribution and cellular origin of type VI collagen in DN. Type VI collagen‐specific oligonucleotide probes and monoclonal antibody were used to assess the relative expression of mRNA for \alpha1 (VI) chain and its translated protein in paraffin‐embedded renal biopsy sections of DN. By immunohistochemistry, compared to the control, increased deposition of type VI collagen was noted in the diffuse and nodular lesions of diabetic glomeruli. For cellular localization of type VI collagen mRNA, paraffin‐embedded renal sections of the control and DN were hybridizedin situwith digoxigenin (Dig)‐labeled antisense oligo‐DNA probe complementary to a part of \alpha1 (VI) mRNA. In comparison to the control kidney sections, increased numbers of intraglomerular cells (both mesangial and epithelial cells) were positive forα1 (VI) mRNA in renal biopsy sections of DN. From the results, we conclude that overexpression of type VI collagen by intraglomerular cells with its increased deposition might significantly contribute to the glomerulosclerosis found in DN.

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