76
|
Mani J, Chaudhary N, Ravat S, Shah PU. Multiple sclerosis: experience in neuroimaging era from western India. Neurol India 1999; 47:8-11. [PMID: 10339701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
31 patients of multiple sclerosis (MS) diagnosed in the last six years in a large teaching hospital were reviewed. The hospital incidence of 0.85% of total admissions in neurology unit in western India is comparable to the series from other parts of India. The mean age at onset was slightly lower compared to other series. The female preponderence was noted in addition to higher incidence of Devic's syndrome. Visual loss (47%) and motor weakness (27%) were the commonest presenting symptoms. The clinical pattern was more similar to Asian series of MS than the western series. All patients underwent magnetic resonance imaging (MRI) scan. 24 out of 25 MRI of Brain and 15 out of 16 MRI of spine were abnormal. CSF immuno-globulins were raised in 80% of patients who underwent CSF study. The data has been compared with other Indian, Asian and Western series.
Collapse
|
77
|
Chaudhary N, Jain A, Gudwani S, Kapoor R, Motwani G. Intramuscular haemangioma of head and neck region. J Laryngol Otol 1998; 112:1199-201. [PMID: 10209624 DOI: 10.1017/s0022215100142859] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Intramuscular haemangiomas are rare benign haemangiomas occurring within the skeletal muscle. These are uncommon tumours in the head and neck region and occur most frequently on the trunk and extremities. Fewer than 80 cases of intra-muscular haemangioma in the head and neck region have been reported in the literature. A case of intramuscular haemangioma of the sternocleidomastoid muscle is presented. The review of occurrence and natural history of such tumours is described and clinical and radiological presentation, histological classifications and treatment modalities are discussed.
Collapse
|
78
|
Mani J, Chaudhary N, Kanjalkar M, Shah PU. Cerebellar ataxia due to lead encephalopathy in an adult. J Neurol Neurosurg Psychiatry 1998; 65:797. [PMID: 9810963 PMCID: PMC2170333 DOI: 10.1136/jnnp.65.5.797] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
79
|
Chaudhary N, Mani J, Rawat S, Mulye R, Shah P. Dopa responsive dystonia in a girl with vitiligo. Indian Pediatr 1998; 35:663-5. [PMID: 10216678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
|
80
|
Chaudhary N, Ravat SH, Shah PU. Phenytoin induced dyskinesia. Indian Pediatr 1998; 35:274-6. [PMID: 9707885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
|
81
|
Jain A, Chaudhary N, Motwani G, Mittal A. Hemifacial microsomia. Indian J Otolaryngol Head Neck Surg 1997; 49:399-401. [PMID: 23119339 PMCID: PMC3450893 DOI: 10.1007/bf02994661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Congenital abnormalities of face emerge as a constellation of malformation of structures which arise from the first and the second branchial arch and the intervening first pharyngeal pouch and the primordia of the temporal bone. When fully expressed, a patient with hemifacial microsomia [Syn: otomandibular dysostosis] exhibits usually unilaterally under developed external or middle ear, mandible, zygoma, maxilla, temporal bone, facial muscles, muscles of masticiation. Many cases however, have been reported where the syndrom is not fully expressed (Crabb 1965).
Collapse
|
82
|
Ojwang JO, Mustain SD, Marshall HB, Rao TS, Chaudhary N, Walker DA, Hogan ME, Akiyama T, Revankar GR, Peyman A, Uhlmann E, Rando RF. Modified antisense oligonucleotides directed against tumor necrosis factor receptor type I inhibit tumor necrosis factor alpha-mediated functions. Biochemistry 1997; 36:6033-45. [PMID: 9166774 DOI: 10.1021/bi970124x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Tumor necrosis factor alpha (TNF alpha), a polypeptide produced by activated macrophages, is a highly pleiotropic cytokine which elicits inflammatory and immunological reactions. The binding of TNF alpha to tumor necrosis factor receptor type I (TNFRI) is considered the initial step responsible for some of the multiple biological functions mediated by TNF alpha. The role of TNF alpha as an inflammatory mediator through human TNFRI makes TNFRI an attractive target for intervention in both acute and chronic inflammatory diseases. In this study, we have identified partial phosphorothioate oligodeoxyribonucleotides (ODNs) containing C-5 propynyl or hexynyl derivatives of 2'-deoxyuridine which specifically inhibited TNFRI and subsequently inhibited the functions of TNF alpha mediated through TNFRI. The most active ODNs were directed against the 3'-poly adenylation signal site on the TNFRI mRNA, and in a cellular assay, gene-specific antisense inhibition occurred in a dose-dependent fashion at submicromolar concentrations, in the presence of Cellfectin. The inhibition of gene expression correlated with the binding affinity of the ODN for the target mRNA. The ODNs lowered TNFRI protein levels and TNF alpha-mediated functions by specifically reducing levels of TNFRI mRNA. These anti-TNFRI ODNs offer a novel approach for controlling biological functions of TNF alpha and may be useful as human therapeutic agents for treating diseases in which TNF alpha has been implicated.
Collapse
MESH Headings
- Antigens, CD/biosynthesis
- Antigens, CD/genetics
- Cells, Cultured
- Dose-Response Relationship, Drug
- Drug Design
- Fibroblasts
- Gene Expression/drug effects
- Humans
- Interleukin-6/biosynthesis
- Interleukin-8/biosynthesis
- Oligonucleotides, Antisense/pharmacology
- RNA Processing, Post-Transcriptional
- RNA, Messenger/metabolism
- Receptors, Tumor Necrosis Factor/biosynthesis
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor, Type I
- Receptors, Tumor Necrosis Factor, Type II
- Thionucleotides/pharmacology
- Toxicity Tests
- Tumor Necrosis Factor-alpha/metabolism
Collapse
|
83
|
Wallace TL, Bazemore SA, Holm K, Markham PM, Shea JP, Chaudhary N, Cossum PA. Pharmacokinetics and distribution of a 33P-labeled anti-human immunodeficiency virus oligonucleotide (AR177) after single- and multiple-dose intravenous administration to rats. J Pharmacol Exp Ther 1997; 280:1480-8. [PMID: 9067338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
AR177 is a 17-mer oligonucleotide that has anti-human immunodeficiency virus activity in vitro. The disposition of internally labeled 33P-AR177 was studied after the tail vein injection of single and multiple doses (0.7 mg/kg) to rats. After a single dose, the terminal half-life of AR177 in the blood and plasma was 367 and 271 hr, respectively, significantly longer than values reported for other oligonucleotides. Analysis of the AR177 tissue distribution showed that the majority of the dose was distributed to the liver (40%), bone marrow (17%) and renal cortex (15%) at 8 hr after single dosing. Analysis of the AR177 concentrations in tissues showed that the highest concentrations were achieved in the renal cortex (15.0 microg-eq/g), liver (7.4 microg-eq/g), bone marrow (3.9 microg-eq/g), mesenteric lymph node (3.0 microg-eq/g) and spleen (2.4 microg-eq/g) at 8 hr after single dosing. The half-life in these tissues was 9.6, 7.7, 36.8, 10.0 and 30.8 days, respectively. Forty-eight hours after the last of seven i.v. doses given every other day, the concentrations in tissues were as follows: renal cortex, 39.9 microg-eq/g; liver, 33.9 microg-eq/g; bone marrow, 12.7 microg-eq/g; spleen, 9.3 microg-eq/g; mesenteric lymph node, 5.1 microg-eq/g. Twenty-one days after administration of the last dose, tissue concentrations were still high, as follows: renal cortex, 18.6 microg-eq/g; liver, 6.2 microg-eq/g; bone marrow, 12.5 microg-eq/g; mesenteric lymph node, 3.9 microg-eq/g; spleen, 8.1 microg-eq/g. There was low urinary and fecal excretion (urinary excretion of 12.8% and fecal excretion of 6.0% of the total dose over 21 days) after a single dose. Gel filtration and anion-exchange high-performance liquid chromatography and electrophoretic analysis of the radioactivity in tissues indicated that >90% of the radioactivity represented intact AR177 for at least 7 days after drug dosing. These results demonstrate that AR177 has an extended plasma, blood and tissue half-life, is widely distributed and achieves high concentrations in lymphoid and nonlymphoid tissues in rats.
Collapse
|
84
|
Bishop JS, Guy-Caffey JK, Ojwang JO, Smith SR, Hogan ME, Cossum PA, Rando RF, Chaudhary N. Intramolecular G-quartet motifs confer nuclease resistance to a potent anti-HIV oligonucleotide. J Biol Chem 1996; 271:5698-703. [PMID: 8621435 DOI: 10.1074/jbc.271.10.5698] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have identified a potentially therapeutic anti-human immunodeficiency virus (HIV)-1 oligonucleotide composed entirely of deoxyguanosines and thymidines (T30177, also known as AR177: 5'-g.tggtgggtgggtggg.t-3', where asterisk indicates phosphorothioate linkage). In acute assay systems using human T-cells, T30177 and its total phosphodiester homologue T30175 inhibited HIV-1-induced syncytium production by 50% at 0.15 and 0.3 microM, respectively. Under physiological conditions, the sequence and composition of the 17-mer favors the formation of a compact, intramolecularly folded structure dominated by two stacked guanine quartet motifs that are connected by three loops of TGs. The molecule is stabilized by the coordination of a potassium ion between the two stacked quartets. We now show that these guanine quartet-containing oligonucleotides are highly resistant to serum nucleases, with t1/2 of 5 h and >4 days for T30175 and T30177, respectively. Both oligonucleotides were internalized efficiently by cells, with intracellular concentrations reaching 5-10-fold above the extracellular levels after 24 h of incubation. In contrast, single-base mutated variants or random sequence control oligonucleotides that could not form the compactly folded structure had markedly reduced half-lives (t1/2 from approximately 3 to 7 min), low cellular uptake, and no sequence-specific anti-HIV-1 activity. These data suggest that the tertiary structure of an oligonucleotide is a key determinant of its nuclease resistance, cellular uptake kinetics, and biological efficacy.
Collapse
|
85
|
Ghaziuddin N, King CA, Naylor MW, Ghaziuddin M, Chaudhary N, Giordani B, Dequardo JR, Tandon R, Greden J. Electroconvulsive treatment in adolescents with pharmacotherapy-refractory depression. J Child Adolesc Psychopharmacol 1996; 6:259-71. [PMID: 9231319 DOI: 10.1089/cap.1996.6.259] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The effectiveness and safety of ECT in pharmacotherapy-refractory depression was examined in 11 hospitalized adolescents (ages 16.3 +/- 1.7 years, 10 females) with a primary DSM-III-R diagnosis of mood disorder, which had failed to respond to three or more adequate trials of antidepressant pharmacotherapy. After a thorough diagnostic evaluation, patients received a course of ECT involving 11.2 +/- 2.0 (range 8-15) administrations. ECT was commenced with bilateral treatment in 2 adolescents and nondominant right electrode placement in 9 patients; 5 of the 9 patients were subsequently changed to bilateral treatment. All 11 patients improved to a clinically significant degree. Significant improvements were noted in scores on the Children Depression Rating Scale-Revised (CDSR-R) and the Global Assessment of Functioning Scale (GAF) (p < 0.05). Euthymia, defined as CDRS-R score < or = 40, was achieved by 64% (7/11) of patients. The Mini-Mental State Examination showed no significant decline in cognitive functioning. Neuropsychological testing completed in 5 subjects both before ECT and 1-5 days after the last treatment, indicated a significant decline in attention, concentration, and long-term memory search. Minor side effects, experienced within the first 12 hours of treatment, were headache (80% of patients) and nausea/vomiting (64%). The potentially serious complication of tardive seizure (after full recovery of consciousness) occurred in 1 adolescent. Prolonged seizures (> 2.5 minutes) were noted in 7 of the 11 patients (9.6% of the 135 ECT administrations). Pending further research on ECT in youth, it is recommended that ECT should only be administered to youth in hospital settings, that all regularly administered psychotropic medications (including antidepressants) be discontinued before ECT and restarted after the final administration of ECT, and that physicians be aware that 12 treatments are usually sufficient, but that 15 treatments may occasionally be necessary for treating depressed adolescents. With the understanding that scientific evaluation of ECT in youth is lacking, it appears that ECT can be an effective and relatively safe treatment for depressed adolescents who have failed to respond to antidepressant pharmacotherapy.
Collapse
|
86
|
Guy-Caffey JK, Bodepudi V, Bishop JS, Jayaraman K, Chaudhary N. Novel polyaminolipids enhance the cellular uptake of oligonucleotides. J Biol Chem 1995; 270:31391-6. [PMID: 8537413 DOI: 10.1074/jbc.270.52.31391] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Two new polyaminolipids have been synthesized for the purpose of improving cellular uptake of oligonucleotides. The amphipathic compounds are conjugates of spermidine or spermine linked through a carbamate bond to cholesterol. The polyaminolipids are relatively nontoxic to mammalian cells. In tissue culture assays, using fluorescent-tagged or radiolabeled triple helix-forming oligonucleotides, spermine-cholesterol and spermidine-cholesterol significantly enhance cellular uptake of the oligomers in the presence of serum. Spermine-cholesterol is comparable with DOTMA/DOPE (a 1:1 (w/w) formulation of the cationic lipid N-[1-(2,3-dioleyloxy)-propyl]-N,N,N-trimethylammonium chloride (DOTMA) and the neutral lipid dioleylphosphatidylethanolamine (DOPE)) in increasing cellular uptake of oligonucleotides, while spermidine-cholesterol is more efficient. The internalized oligonucleotides are routed to the nucleus as early as 20 min after treatment, suggesting that the polyaminolipids increase the permeability of cellular membranes to oligonucleotides. At later times, much of the incoming oligonucleotides are sequestered within punctate cytoplasmic granules, presumably compartments of endosomal origin. Coadministration with polyaminolipids markedly improves the cellular stability of the oligonucleotides; more than 80% of the material can be recovered intact up to 24 h after addition to cells. In the absence of the polyaminolipids, nearly all of the material is degraded within 6 h. These data suggest that the new polyaminolipids may be useful for the delivery of nucleic acid-based therapeutics into cells.
Collapse
|
87
|
Jayaraman K, Durland RH, Rao TS, Revankar GR, Bodepudi V, Chaudhary N, Guy-Caffey J. Approaches to Enhance the Binding Affinity and Nuclease Stability of Triplex Forming Oligonucleotides. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 1995. [DOI: 10.1080/15257779508012509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
88
|
Abstract
The nuclear envelope consists of three distinct membrane domains: the outer membrane with the bound ribosomes, the inner membrane with the bound lamina, and the pore membrane with the bound pore complexes. Using biochemical and morphological methods, we observed that the nuclear membranes of HeLa cells undergoing mitosis are disassembled in a domain-specific manner, i.e., integral membrane proteins representing the inner nuclear membrane (the lamin B receptor) and the nuclear pore membrane (gp210) are segregated into different populations of mitotic vesicles. At the completion of mitosis, the inner nuclear membrane-derived vesicles associate with chromatin first, beginning in anaphase, whereas the pore membranes and the lamina assemble later, during telophase and cytokinesis. Our data suggest that the ordered reassembly of the nuclear envelope is triggered by the early attachment of inner nuclear membrane-derived vesicles to the chromatin.
Collapse
|
89
|
Hytiroglou P, Choi SW, Theise ND, Chaudhary N, Worman HJ, Thung SN. The expression of nuclear lamins in human liver: an immunohistochemical study. Hum Pathol 1993; 24:169-72. [PMID: 8381765 DOI: 10.1016/0046-8177(93)90296-s] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The nuclear lamina is a meshwork of intermediate filaments adjacent to the inner nuclear membrane that in mammalian cells is predominantly composed of three proteins: lamin A, lamin B, and lamin C. Because lamin A and C (A-type lamins) expression has been shown to be lacking in several types of undifferentiated or rapidly proliferating cells, we investigated lamin expression in the human liver in conditions with hepatocellular regeneration (cirrhosis of various etiologies and macroregenerative nodules) and in hepatocellular carcinomas of various grades of differentiation. Immunohistochemical stains for A-type lamins and lamin B were performed on frozen tissue sections with the avidin-biotin complex method. Normal and regenerating hepatocytes, biliary epithelial cells (ductal and ductular cells), and hepatocellular carcinoma cells invariably expressed both A-type lamins and lamin B. These findings indicate that in hepatocellular regeneration and malignant transformation the production of both A-type lamins and lamin B is preserved.
Collapse
|
90
|
Chaudhary N, McMahon C, Blobel G. Primary structure of a human arginine-rich nuclear protein that colocalizes with spliceosome components. Proc Natl Acad Sci U S A 1991; 88:8189-93. [PMID: 1896467 PMCID: PMC52472 DOI: 10.1073/pnas.88.18.8189] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The cDNA for a 54-kDa nuclear protein (p54) has been cloned from a human hepatoma expression library. Contained within p54 is an arginine/serine-rich region similar to segments of several proteins that participate in pre-mRNA splicing including the 70-kDa component of U1 small nuclear and "suppressor-of-white-apricot" proteins. The arginine/serine-rich region is dominated by a series of 8-amino acid imperfect repetitive motifs (consensus sequence, Arg-Arg-Ser-Arg-Ser-Arg-Ser-Arg). Antibodies raised against synthetic peptides of p54 react with an approximately 70-kDa protein on immunoblots of HeLa cell and rat liver nuclear proteins. This apparent discrepancy in mass is also observed when p54 mRNA is translated in vitro. Indirect immunofluorescence studies in HeLa cells show that p54 is distributed throughout the nucleus in a speckled pattern, with an additional diffuse labeling of the nucleus excluding the nucleoli. Double immunofluorescence experiments indicate that these punctate regions are coincident with the speckles seen in cells stained with antibodies against several constituents of the pre-mRNA splicing machinery. Sedimentation analysis of HeLa cell extracts on sucrose gradients showed that p54 migrates at 4-6 S, indicating that the protein is not a tightly associated component of snRNPs. Although the function of p54 is not yet known, our structure and immunolocalization data suggest that this protein may have a role in pre-mRNA processing.
Collapse
|
91
|
Courvalin JC, Chaudhary N, Danon F, Brouet JC, Lassoued K. Characterization of human autoantibodies specific for lamin A. Biol Cell 1990; 69:93-7. [PMID: 2271902 DOI: 10.1111/j.1768-322x.1990.tb00003.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We have characterized human autoimmune polyclonal antibodies reactive with lamin A, a 74 kDa peripheral protein of the nuclear envelope. Unlike other known antibodies to lamin A, the antibodies described here do not crossreact with the structurally related lamin C. These antibodies feature only chi light chains suggesting that their specificity is restricted to a limited number of epitopes. Based on the known amino acid sequence of human lamins A and C, the epitope(s) are most likely located in the 80 amino acid carboxyl tail of mature lamin A.
Collapse
|
92
|
Reeves WH, Chaudhary N, Salerno A, Blobel G. Lamin B autoantibodies in sera of certain patients with systemic lupus erythematosus. J Exp Med 1987; 165:750-62. [PMID: 3546581 PMCID: PMC2188284 DOI: 10.1084/jem.165.3.750] [Citation(s) in RCA: 67] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Sera from four patients with systemic lupus erythematosus containing antibodies that yield nuclear rim staining of HEp-2 cells by indirect immunofluorescence were identified and characterized. Each serum contained autoantibodies reacting strongly with lamin B on western blots. One of the four sera displayed weaker reactivity with lamins A and C, while the other three displayed only minimal reactivity with lamins A and C. Titers of antilamin antibodies ranged from 1:1,250 to 1:36,250. Two of the sera also reacted at a dilution of 1:20 with cytoplasmic filaments of PTK-2 cells, suggesting that a small fraction of the autoantibodies in these sera may bind to alpha-helical domains of the lamins that are homologous to those of intermediate filaments. The majority of the antilamin antibodies in these patients' sera are specific for portions of the lamin B molecule that are not homologous to lamins A and C, however. The findings suggest that autoantibodies to the nuclear lamina may, in some instances, be responsible for a rim pattern in the fluorescent antinuclear antibody assay. In addition, autoantibodies to the nuclear lamina in sera of certain patients with systemic lupus erythematosus may be useful for defining the molecular structure and biological functions of lamin B, as well as for studying mechanisms of autoimmunity.
Collapse
|
93
|
Fisher DZ, Chaudhary N, Blobel G. cDNA sequencing of nuclear lamins A and C reveals primary and secondary structural homology to intermediate filament proteins. Proc Natl Acad Sci U S A 1986; 83:6450-4. [PMID: 3462705 PMCID: PMC386521 DOI: 10.1073/pnas.83.17.6450] [Citation(s) in RCA: 478] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The amino acid sequences deduced from cDNA clones of human lamin A and lamin C show identity between these two lamins except for an extra 9.0-kDa carboxyl-terminal tail that is present only in lamin A. Both lamins A and C contain an alpha-helical domain of approximately 360 residues that shows striking homology to a corresponding alpha-helical rod domain that is the structural hallmark of all intermediate filament proteins. However, the lamin alpha-helical domain is 14% larger than that of the intermediate filament proteins. In addition to the extensive homology to intermediate filament proteins as reported [McKeon, F., Kirschner, M. & Caput, D. (1986) Nature (London) 319, 463-468], a different 82-amino acid residue stretch at the carboxyl terminus of lamin A has been deduced and verified by amino acid sequencing. This region contains sequence homology to amino- and carboxylterminal domains of type I and type II epidermal keratins. Implications of the presence of these and other domains in lamins A and C for the assembly of the nuclear lamina are discussed.
Collapse
|
94
|
Rip JW, Chaudhary N, Carroll KK. The submicrosomal distribution of dolichyl phosphate and dolichyl phosphate phosphatase in rat liver. J Biol Chem 1983; 258:14926-30. [PMID: 6317680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Rat liver microsomes were isolated and fractionated into Golgi, smooth endoplasmic reticulum (SER), and rough endoplasmic reticulum (RER), and the purity of these preparations was determined. The dolichyl phosphate (Dol-P) content of whole microsomes and of each of the submicrosomal fractions was estimated using high pressure liquid chromatography. Dol-P accounts for 4 and 40% of the sum of the alcohol, the fatty acyl esters of dolichol, and monophosphate forms present in whole liver and in purified microsomes, respectively. Concentrations equal to 58, 77, and 108 ng of Dol-P/mg of protein were found in Golgi, SER, and RER, respectively. These values represent 3, 36, and 54% of the sum of the alcohol, the fatty acyl esters of dolichol, and monophosphate forms present in each of these same fractions, respectively. Increases in the Dol-P content of rat liver were observed as early as 12 h after turpentine-induced inflammation and increased 2-fold over 36 h. In this system, Dol-P accounts for no more than 50% of the sum of all phosphorylated and pyrophosphorylated dolichol intermediates present. The specific activity for dolichyl phosphate phosphatase was highest by more than a factor of 2 in Golgi membrane. Specific activities obtained for SER and RER were 42 and 11% of those present in Golgi. The major requirement for Dol-P is thought to be for the saccharide and oligosaccharide transferase reactions which are presumed to take place in RER. The discovery of significant quantities of Dol-P in Golgi and SER is consistent with a possible role of Dol-P in the transport of sugars required for glycoprotein synthesis and processing from a cytosolic to luminal orientation.
Collapse
|
95
|
Rip JW, Chaudhary N, Carroll KK. Distribution and metabolism of dolichol and dolichyl phosphate in rat liver. CANADIAN JOURNAL OF BIOCHEMISTRY AND CELL BIOLOGY = REVUE CANADIENNE DE BIOCHIMIE ET BIOLOGIE CELLULAIRE 1983; 61:1025-31. [PMID: 6313169 DOI: 10.1139/o83-131] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The dolichol and dolichyl phosphate (Dol-P) content of various tissues and liver subcellular fractions obtained from rats have been measured directly using high pressure liquid chromatographic methods developed in this laboratory. Spleen contained the highest concentration of dolichol, while other tissues including serum had smaller amounts. Although considerable differences in homologue distribution patterns were observed among the tissues examined, a number of purified subcellular fractions obtained from liver (nuclei, mitochondria, cytosol, and microsomes) exhibited a single common pattern. Only some 5% of liver dolichol appeared in the microsomal compartment of the cell where glycoprotein formation occurs, while 50% of the dolichol in this tissue was found in a lysosome-enriched fraction. The concentrations of dolichol present in liver nuclei, mitochondria, whole microsomes (also rough and smooth, endoplasmic recticulum (RER and SER, respectively), and cytosol were considerably lower (on a protein basis) than those present in whole liver. Besides the lysosome-enriched fraction, only plasma membranes and Golgi contained dolichol at concentrations equal to or greater than those present in liver homogenates. The low concentrations of dolichol found in microsomes suggest that the amounts of dolichol available for Dol-P formation via the CTP-dependent kinase reaction may be rate limiting. Most of the Dol-P in liver could be recovered in the microsomal fraction. Dol-P accounted for 4 and 40% of the sum of alcohol + dolichyl fatty acyl ester + Dol-P forms present in whole liver and in microsomes, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|
96
|
Chugh KS, Malik GH, Singhal PC, Malik N, Chaudhary N, Mehta RL, Narayan G. Acute renal failure due to drug induced acute interstitial nephritis. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 1982; 30:819-22. [PMID: 7185824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
97
|
Chaudhary N, Freeman DJ, Rip JW, Carroll KK. Direct estimation of dolichyl phosphate in rat liver by high pressure liquid chromatography. Lipids 1982; 17:558-60. [PMID: 7132586 DOI: 10.1007/bf02535384] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
98
|
Rupar CA, Rip JW, Chaudhary N, Carroll KK. The subcellular localization of enzymes of dolichol metabolism in rat liver. J Biol Chem 1982; 257:3090-4. [PMID: 6277925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Dolichyl phosphate is an intermediate in the glycosylation of N-glycosamidic linked glycoproteins in mammalian systems, and its availability may be a limiting factor in glycoprotein biosynthesis. The basic kinetics and subcellular distribution of enzymes which may influence the concentration of dolichyl phosphate in rat liver have therefore been investigated. These include dolichyl phosphate phosphatase, dolichol phosphokinase, dolichyl fatty acyl ester synthetase, GDP-mannose dolichyl phosphate mannosyl transferase, and UDP-glucose dolichyl phosphate glucosyl transferase. The specific activity of the enzymes was highest in the microsomes, except for dolichyl phosphate phosphatase and dolichyl fatty acyl ester synthetase, which were most concentrated in the plasma membrane and the cytosol fraction, respectively. The nuclei contained all of the enzyme activities while the mitochondria and cytoplasm were generally less active. The presence of both dolichol phosphokinase and dolichyl phosphate phosphatase in microsomes and nuclei, which contain the highest glycosyl transferase activities, may provide a means for direct enzymatic control of levels of dolichyl phosphate.
Collapse
|
99
|
Rupar CA, Rip JW, Chaudhary N, Carroll KK. The subcellular localization of enzymes of dolichol metabolism in rat liver. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)81077-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
100
|
Rip JW, Rupar CA, Chaudhary N, Carroll KK. Localization of a dolichyl phosphate phosphatase in plasma membranes of rat liver. J Biol Chem 1981; 256:1929-34. [PMID: 6257694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
|