Presence of a specific protein factor in the amniotic fluid of women with an anomalous fetus

1998 ◽  
Vol 5 (1) ◽  
pp. 150A-150A
Author(s):  
M MARCOTTE ◽  
R NAZ
Keyword(s):  
Amniotic Fluid ◽  
Specific Protein ◽  
Protein Factor

Extinction of phosphoenolpyruvate carboxykinase gene expression is associated with loss of a specific chromatin-binding protein from a far upstream domain

1990 ◽  
Vol 10 (7) ◽  
pp. 3782-3787
Author(s):  
Y T Ip ◽  
R E Fournier ◽  
R Chalkley
Keyword(s):  
Chromatin Structure ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Specific Protein ◽  
Gene Activity ◽  
Upstream Region ◽  
Hypersensitive Site ◽  
Chromosome 11 ◽  
Protein Factor ◽  
Hypersensitive Sites ◽  
Liver Gene

We have analyzed the chromatin structure of the phosphoenolpyruvate carboxykinase (PEPCK) gene in hepatoma x fibroblast hybrids with different extinction phenotypes. These hybrids included a karyotypically complete hybrid in which all liver gene activity was extinguished, a microcell hybrid that contained a single mouse chromosome 11 and in which PEPCK gene activity was decreased but inducible by cyclic AMP, and a segregant line that had lost all mouse chromosomes and in which the PEPCK gene was reexpressed. We found that only in the completely extinguished hybrid was PEPCK chromatin structure radically different from that in the parental hepatoma cells. In this hybrid, there was no evidence of any factors binding to the promoter or to the upstream hypersensitive site at -4800 base pairs. In the other cell lines, even when PEPCK gene transcription was low, the PEPCK chromatin showed characteristic structures typical of a transcriptionally competent gene, with hypersensitive sites at positions previously described. Loss of the upstream hypersensitive site was also shown to be correlated with the absence of a liver-specific protein factor that binds specifically to the upstream region.

scholarly journals Extinction of phosphoenolpyruvate carboxykinase gene expression is associated with loss of a specific chromatin-binding protein from a far upstream domain.

1990 ◽  
Vol 10 (7) ◽  
pp. 3782-3787 ◽  
Author(s):  
Y T Ip ◽  
R E Fournier ◽  
R Chalkley
Keyword(s):  
Chromatin Structure ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Specific Protein ◽  
Gene Activity ◽  
Upstream Region ◽  
Hypersensitive Site ◽  
Chromosome 11 ◽  
Protein Factor ◽  
Hypersensitive Sites ◽  
Liver Gene

We have analyzed the chromatin structure of the phosphoenolpyruvate carboxykinase (PEPCK) gene in hepatoma x fibroblast hybrids with different extinction phenotypes. These hybrids included a karyotypically complete hybrid in which all liver gene activity was extinguished, a microcell hybrid that contained a single mouse chromosome 11 and in which PEPCK gene activity was decreased but inducible by cyclic AMP, and a segregant line that had lost all mouse chromosomes and in which the PEPCK gene was reexpressed. We found that only in the completely extinguished hybrid was PEPCK chromatin structure radically different from that in the parental hepatoma cells. In this hybrid, there was no evidence of any factors binding to the promoter or to the upstream hypersensitive site at -4800 base pairs. In the other cell lines, even when PEPCK gene transcription was low, the PEPCK chromatin showed characteristic structures typical of a transcriptionally competent gene, with hypersensitive sites at positions previously described. Loss of the upstream hypersensitive site was also shown to be correlated with the absence of a liver-specific protein factor that binds specifically to the upstream region.

scholarly journals Post-translational regulation of activation-induced cytidine deaminase

2008 ◽  
Vol 364 (1517) ◽  
pp. 667-673 ◽  
Author(s):  
Uttiya Basu ◽  
Andrew Franklin ◽  
Frederick W Alt
Keyword(s):  
Translational Regulation ◽  
Somatic Hypermutation ◽  
Cytidine Deaminase ◽  
Specific Protein ◽  
Antibody Repertoire ◽  
Dna Modification ◽  
Class Switch ◽  
Protein Factor ◽  
Activation Induced Cytidine Deaminase

The assembled immunoglobulin genes in the B cells of mice and humans are altered by distinct processes known as class switch recombination (CSR) and somatic hypermutation, leading to diversification of the antibody repertoire. These two DNA modification processes are initiated by the B cell-specific protein factor activation-induced cytidine deaminase (AID). AID is post-translationally modified by phosphorylation at multiple sites, although functional significance during CSR has been implicated only for phosphorylation at serine-38 (S38). Although multiple laboratories have demonstrated that AID function is regulated via phosphorylation at S38, the precise biological role of S38 phosphorylation has been a topic of debate. Here, we discuss our interpretation of the significance of AID regulation via phosphorylation and also discuss how this form of AID regulation may have evolved in higher organisms.

Mitochondrial nitric oxide synthase and its role in the mechanisms of cell adaptation to hypoxia

2016 ◽  
Vol 14 (2) ◽  
pp. 38-46 ◽  
Author(s):  
Vasiliy E Novikov ◽  
Olga S Levchenkova ◽  
Elena V Pozhilova
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Specific Protein ◽  
New Drugs ◽  
Adaptation To Hypoxia ◽  
Cell Adaptation ◽  
Protein Factor ◽  
Action Analysis ◽  
Mitochondrial Nitric Oxide Synthase ◽  
Oxide Synthase

Mitochondrial nitric oxide synthase (mtNOS) actively participates in mechanisms of regulation of cell adaptation to extreme factors. It is closely interacted with other mitochondrial regulatory factors and is involved in adaptation reactions of cells to hypoxia, ischemia and other pathogenic action. Analysis of the role of mtNOS in cell functioning in hypoxia condition and its influence on apoptosis is presented in the article. Complex mechanism of cell adaptation with participation of mitochondrial nitric oxide (NO) is considered. Mitochondrial NO is a modulator of cell respiration, synthesis of ATP, activity of mitochondrial ATP-sensitive potassium channels, mitochondrial megapore and the specific protein factor to hypoxia adaptation. The possibility of pharmacological regulation of mtNOS activity is discussed. This approach seems to be promising for searching of new drugs for the pharmacotherapy of diseases with hypoxia and ischemia in their pathogenesis. There is possible to regulate cell homeostasis, for example, resistance to hypoxia by modulating the activity of mtNOS and synthesis of mitochondrial NO.

Severe coagulation factor V deficiency caused by 2 novel frameshift mutations: 2952delT in exon 13 and 5493insG in exon 16 of factor 5 gene

Blood ◽  
2002 ◽  
Vol 99 (2) ◽  
pp. 702-705 ◽  
Author(s):  
Éva Ajzner ◽  
István Balogh ◽  
Teréz Szabó ◽  
Anikó Marosi ◽  
Gizella Haramura ◽  
...  
Keyword(s):  
Light Chain ◽  
Weight Ratio ◽  
Coagulation Factor ◽  
Male Infant ◽  
Specific Protein ◽  
Enzyme Linked Immunosorbent Assay ◽  
Severe Bleeding ◽  
Factor V ◽  
Bleeding Tendency ◽  
Protein Factor

Abstract A male infant with severe bleeding tendency had undetectable factor V activity. Sequence analysis of the proband's DNA revealed one base deletion in exon 13 (2952delT) and one base insertion in exon 16 (5493insG) in heterozygous form. Both mutations introduced a frameshift and a premature stop at codons 930 and 1776, respectively. The proband's father and mother were heterozygous for 2952delT and for 5493insG, respectively. Both mutations would result in the synthesis of truncated proteins lacking complete light chain or its C-terminal part. In the patient's plasma, no factor V light chain was detected by enzyme-linked immunosorbent assay. The N-terminal portion of factor V containing the heavy chain, and the connecting B domain was severely reduced but detectable (1.7%). A small amount of truncated factor V–specific protein with a molecular weight ratio of 236 kd could be immunoprecipitated from the plasma and detected by Western blotting. This protein, factor VDebrecen, corresponds to the translated product of exon 16 mutant allele.

Nucleosomal instability and induction of new upstream protein-DNA associations accompany activation of four small heat shock protein genes in Drosophila melanogaster

1986 ◽  
Vol 6 (3) ◽  
pp. 779-791
Author(s):  
I L Cartwright ◽  
S C Elgin
Keyword(s):  
Heat Shock ◽  
Heat Shock Protein ◽  
Structural Changes ◽  
Consensus Sequence ◽  
Small Heat Shock Protein ◽  
Specific Protein ◽  
Dnase I ◽  
Coding Region ◽  
Protein Factor ◽  
Heat Shock Protein Genes

We investigated in detail the structural changes that occur in nuclear chromatin upon activation of the four small heat shock protein genes in D. melanogaster. Both the chemical cleavage reagent methidiumpropyl-EDTA X iron(II) [MPE X Fe(II)] and the nuclease DNase I revealed a complex pattern of four or five hypersensitive sites upstream of each gene before activation. In addition, MPE X Fe(II) detected a short positioned array of nucleosomes located on each coding region. Upon heat shock activation a number of changes in the patterns occurred. For each gene, at least one of the upstream hypersensitive regions was eliminated or substantially shifted in position. Regions were established which became highly refractile to digestion by either MPE X Fe(II) or DNase I and, as such, appeared as small "footprints" in the pattern. The location of these refractile regions relative to the cap site varied for each gene examined. The coding regions themselves became highly accessible to DNase I. The nucleosomal arrays detected by MPE X Fe(II) were characterized by a considerable loss of detail and significantly enhanced accessibility, the extent of which probably reflected the relative transcription rate of each gene. Careful mapping of the location and extent of each upstream footprint and comparison with the DNA sequence revealed the presence at each location of two (or more) contiguous or overlapping segments that bear high homology to the heat shock consensus sequence C-T-N-G-A-A-N-N-T-T-C-N-A-G. A specific protein factor (or factors) is most likely bound at or near these sequence in heat-shocked Drosophila cells.

Novel signalling mechanism and clinical applications of sperm-specific PLCζ

2015 ◽  
Vol 43 (3) ◽  
pp. 371-376 ◽  
Author(s):  
Michail Nomikos
Keyword(s):  
Embryonic Development ◽  
Mammalian Species ◽  
Specific Protein ◽  
Ph Domain ◽  
Substantial Evidence ◽  
Catalytic Domains ◽  
Protein Factor ◽  
Physiological Properties ◽  
Intracellular Vesicles ◽  
Ef Hands

Egg activation is the first step of embryonic development and in mammals is triggered by a series of cytoplasmic calcium (Ca2+) oscillations. Sperm–egg fusion initiates these Ca2+ oscillations by introducing a sperm-specific protein factor into the egg cytoplasm. Substantial evidence indicates that this protein is a sperm-specific phospholipase C (PLC), termed PLC-zeta (PLCζ). PLCζ stimulates cytoplasmic Ca2+ oscillations matching those at fertilization triggering early embryonic development in several mammalian species. Structurally, PLCζ is comprised of four EF-hands, a C2 domain, and X and Y catalytic domains. PLCζ is an unusual PLC since it lacks a pleckstrin homology (PH) domain. It is also distinctive in that its X–Y linker is not involved in auto-inhibition of catalytic activity, but instead binds to phosphatidylinositol 4,5-bisphosphate (PIP2). Moreover, relative to other PLC isoforms, PLCζ possesses unique potency in stimulating Ca2+ oscillations in eggs, although it does not appear to bind to plasma membrane PIP2. In contrast, PLCζ appears to interact with intracellular vesicles in eggs that contain PIP2. I discuss the recent advances in our knowledge of the intriguing biochemical and physiological properties of sperm PLCζ and postulate potential roles for PLCζ in terms of clinical diagnosis and therapy for certain forms of male infertility.

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