scholarly journals Faculty Opinions recommendation of A Multiplex Enzymatic Machinery for Cellular Protein S-nitrosylation.

2018 ◽  
Author(s):  
David Cánovas
Keyword(s):  
Protein S ◽  
Cellular Protein ◽  
Enzymatic Machinery

scholarly journals A Multiplex Enzymatic Machinery for Cellular Protein S-nitrosylation

2018 ◽  
Vol 69 (3) ◽  
pp. 451-464.e6 ◽  
Author(s):  
Divya Seth ◽  
Douglas T. Hess ◽  
Alfred Hausladen ◽  
Liwen Wang ◽  
Ya-juan Wang ◽  
...  
Keyword(s):  
Protein S ◽  
Cellular Protein ◽  
Enzymatic Machinery

scholarly journals Binding of CCAAT Displacement Protein CDP to Adenovirus Packaging Sequences

2003 ◽  
Vol 77 (11) ◽  
pp. 6255-6264 ◽  
Author(s):  
Ece Erturk ◽  
Philomena Ostapchuk ◽  
Susanne I. Wells ◽  
Jihong Yang ◽  
Keqin Gregg ◽  
...  
Keyword(s):  
Protein S ◽  
Cellular Protein ◽  
Dna Packaging ◽  
Sequence Motif ◽  
Uncharacterized Protein ◽  
Virus Particles ◽  
Ccaat Displacement Protein ◽  
Viral Dna Packaging

ABSTRACT Adenovirus (Ad) type 5 DNA packaging is initiated in a polar fashion from the left end of the genome. The packaging process is dependent upon the cis-acting packaging domain located between nucleotides 194 and 380. Seven A/T-rich repeats have been identified within this domain that direct packaging. A1, A2, A5, and A6 are the most important repeats functionally and share a bipartite sequence motif. Several lines of evidence suggest that there is a limiting trans-acting factor(s) that plays a role in packaging. Two cellular activities that bind to minimal packaging domains in vitro have been previously identified. These binding activities are P complex, an uncharacterized protein(s), and chicken ovalbumin upstream promoter transcription factor (COUP-TF). In this work, we report that a third cellular protein, octamer-1 protein (Oct-1), binds to minimal packaging domains. In vitro binding analyses and in vivo packaging assays were used to examine the relevance of these DNA binding activities to Ad DNA packaging. The results of these experiments reveal that COUP-TF and Oct-1 binding does not play a functional role in Ad packaging, whereas P-complex binding directly correlates with packaging function. We demonstrate that P complex contains the cellular protein CCAAT displacement protein (CDP) and that full-length CDP is found in purified virus particles. In addition to cellular factors, previous evidence indicates that viral factors play a role in the initiation of viral DNA packaging. We propose that CDP, in conjunction with one or more viral proteins, binds to the packaging sequences of Ad to initiate the encapsidation process.

scholarly journals Recent advances in the regulation of plant immunity by S-nitrosylation

2020 ◽  
Author(s):  
Jibril Lubega ◽  
Saima Umbreen ◽  
Gary J Loake
Keyword(s):  
Plant Immunity ◽  
Protein S ◽  
Cellular Protein ◽  
Effector Proteins ◽  
Host Cells ◽  
Immune Functions ◽  
Post Translational Modification ◽  
No Donor ◽  
Reactive Protein ◽  
Recent Advances

Abstract S-nitrosylation, the addition of a nitric oxide (NO) moiety to a reactive protein cysteine (Cys) thiol, to form a protein S-nitrosothiol (SNO), is emerging as a key regulatory post-translational modification (PTM) to control the plant immune response. NO also S-nitrosylates the antioxidant tripeptide, glutathione, to form S-nitrosoglutathione (GSNO), both a storage reservoir of NO bioactivity and a natural NO donor. GSNO and, by extension, S-nitrosylation, are controlled by GSNO reductase1 (GSNOR1). The emerging data suggest that GSNOR1 itself is a target of NO-mediated S-nitrosylation, which subsequently controls its selective autophagy, regulating cellular protein SNO levels. Recent findings also suggest that S-nitrosylation may be deployed by pathogen-challenged host cells to counteract the effect of delivered microbial effector proteins that promote pathogenesis and by the pathogens themselves to augment virulence. Significantly, it also appears that S-nitrosylation may regulate plant immune functions by controlling SUMOylation, a peptide-based PTM. In this context, global SUMOylation is regulated by S-nitrosylation of SUMO conjugating enzyme 1 (SCE1) at Cys139. This redox-based PTM has also been shown to control the function of a key zinc finger transcriptional regulator during the establishment of plant immunity. Here, we provide an update of these recent advances.

Abstract 20500: Trx1 Promotes Trans-Nitrosylation of Cellular Proteins to Stimulate Autophagy and Cell Survival

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Narayani Nagarajan ◽  
Sebastiano Sciarretta ◽  
Junichi Sadoshima
Keyword(s):  
Cell Survival ◽  
Critical Role ◽  
Protein S ◽  
Cellular Protein ◽  
Cellular Proteins ◽  
Redox Activity ◽  
Energy Stress ◽  
Biotin Switch

Thioredoxin-1 (Trx1) is cardioprotective during oxidative stress, mainly through its antioxidant activity. Trx1 is also S-nitrosylated and, in turn, trans-nitrosylates other proteins. However, the role of Trx1-dependent S-nitrosylation in cardiomyocytes (CMs) is unknown. Here, we investigated the role of Trx1-mediated protein S-nitrosylation in the regulation of CM survival during stress in vitro. Using biotin-switch assays, we found that wild-type Trx1 (Trx1WT) is S-nitrosylated at baseline, but the extent of S-nitrosylation was attenuated in Trx1C73S, suggesting that Trx1 is S-nitrosylated at Cys73. Trx1WT and Trx1C73S do not differ in their redox activity, as determined by Amplex Red assays. Cellular protein S-nitrosylation levels were increased after 4 hours of glucose deprivation (GD), an energy stress condition (1.64±0.27 fold, p<0.05), as determined by biotin switch assays. Overexpression of Trx1WT increased (3.94-fold), whereas knockdown of Trx1 (0.66±0.01 fold, p<0.01) or overexpression of Trx1C73S (0.77±0.02 fold, p<0.01) decreased, total protein S-nitrosylation in response to GD. These results suggest that Trx1C73 regulates protein S-nitrosylation in CMs during GD. Overexpression of Trx1 increased CM survival after 24 hours of GD (1.42±0.08 fold vs LacZ, p<0.05), as evaluated with propidium iodide assays. Conversely, shTrx1 (2.13±0.05 fold vs control, p<0.01) or Trx1C73S (1.73±0.034 fold vs LacZ, p<0.01) increased cell death during GD. Either knockdown of Trx1 (LC3-II/Tubulin: 0.55 fold vs control) or overexpression of Trx1C73S (vs LacZ: LC3-II/Tubulin, 0.60 fold; autophagosomes, 0.83±0.16-fold, p<0.005; autolysosomes, 0.62±0.13-fold, p<0.005) significantly decreased autophagy during GD. Mechanistically, Trx1 co-immunoprecipitates with Atg7, an E1-like protein which plays a critical role in mediating autophagy. Using mass spectroscopy analyses, we found that SNO-Trx1 can trans-nitrosylate Atg7 in vitro. These results suggest that Trx1 trans-nitrosylates Atg7 during GD. Taken all together, our results indicate that Trx1 promotes trans-nitrosylation of cellular proteins, including Atg7, and autophagy, thereby promoting cell survival during energy stress in CMs.

scholarly journals Retrotransposon Target Site Selection by Imitation of a Cellular Protein

2007 ◽  
Vol 28 (4) ◽  
pp. 1230-1239 ◽  
Author(s):  
Troy L. Brady ◽  
Peter G. Fuerst ◽  
Robert A. Dick ◽  
Clarice Schmidt ◽  
Daniel F. Voytas
Keyword(s):  
Molecular Mimicry ◽  
Mobile Element ◽  
Protein S ◽  
Cellular Protein ◽  
Mobile Elements ◽  
General Mechanism ◽  
Heterochromatin Protein ◽  
Cellular Processes ◽  
Cellular Factors ◽  
Functional Equivalency

ABSTRACT Mobile elements rely on cellular processes to replicate, and therefore, mobile element proteins frequently interact with a variety of cellular factors. The integrase (IN) encoded by the retrotransposon Ty5 interacts with the heterochromatin protein Sir4, and this interaction determines Ty5's preference to integrate into heterochromatin. We explored the hypothesis that Ty5's targeting mechanism arose by mimicking an interaction between Sir4 and another cellular protein(s). Mutational analyses defined the requirements for the IN-Sir4 interaction, providing criteria to screen for cellular analogues. Esc1, a protein associated with the inner nuclear membrane, interacted with the same domain of Sir4 as IN, and 75% of mutations that disrupted IN-Sir4 interactions also abrogated Esc1-Sir4 interactions. A small motif critical for recognizing Sir4 was identified in Esc1. The functional equivalency of this motif and the Sir4-interacting domain of IN was demonstrated by swapping these motifs and showing that the chimeric IN and Esc1 proteins effectively target integration and partition DNA, respectively. We conclude that Ty5 targets integration by imitating the Esc1-Sir4 interaction and suggest molecular mimicry as a general mechanism that enables mobile elements to interface with cellular processes.

scholarly journals Negative regulatory regions of the PAT1 promoter of Hz-1 virus contain GATA elements which associate with cellular factors and regulate promoter activity

2001 ◽  
Vol 82 (2) ◽  
pp. 313-320 ◽  
Author(s):  
Hong-Hwa Chen ◽  
Feng-Yuan Tsai ◽  
Chung-Te Chen
Keyword(s):  
Promoter Activity ◽  
Protein S ◽  
Cellular Protein ◽  
Computer Assisted ◽  
Mobility Shift ◽  
Cellular Factors ◽  
Negative Effect ◽  
Assisted Analysis ◽  
Autographa Californica Multiple Nucleopolyhedrovirus ◽  
Negative Regulatory Role

The persistence-associated transcript 1 (PAT1) is actively expressed during persistent infection with Hz-1 virus, while transcription of the rest of the viral genes is shut down. Previously, results of a series deletion of the PAT1 promoter suggested that the regions from nucleotides −312 to −212 and nucleotides −158 to −90 negatively regulate the promoter activity. Here, the negative regulatory effect of the −312/−90 fragment was confirmed using a heterologous IE0 promoter of Autographa californica multiple nucleopolyhedrovirus. Further, the negative regulation of the −312 to −212 region was orientation-independent. The results of electrophoresis mobility shift assays showed that cellular protein(s) bind specifically to DNA fragments −312/−212 and −158/−90. In each of these fragments, a GATA element was identified by computer-assisted analysis. Mutating both GATA elements in the −312/−90 fragment completely eliminated its negative effect on IE0 promoter activity, while mutating only one of these elements had little or no effect. Together, these results suggest that the GATA element has a negative regulatory role on the IE0 and PAT1 promoters.

scholarly journals Erythropoietin induces tyrosine phosphorylation and kinase activity of the c-fps/fes proto-oncogene product in human erythropoietin-responsive cells

Blood ◽  
1993 ◽  
Vol 81 (12) ◽  
pp. 3193-3196 ◽  
Author(s):  
Y Hanazono ◽  
S Chiba ◽  
K Sasaki ◽  
H Mano ◽  
Y Yazaki ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Tyrosine Phosphorylation ◽  
Kinase Activity ◽  
Protein S ◽  
Receptor Activation ◽  
Kinase Domain ◽  
Cellular Protein ◽  
Erythroid Progenitor ◽  
Nonreceptor Tyrosine Kinase ◽  
Human Erythropoietin

Erythropoietin (EPO) is a hematopoietic growth factor that stimulates the proliferation and differentiation of erythroid progenitor cells. Although the EPO receptor has no kinase domain, EPO rapidly induces tyrosine phosphorylation of several proteins in EPO-responsive cells. Therefore, the receptor activation by the ligand could induce tyrosine- kinase activity of unidentified cellular protein(s). Here we show that c-fps/fes proto-oncogene product (p92c-fes), nonreceptor tyrosine kinase, is tyrosine-phosphorylated on treatment with EPO in a human erythroleukemia cell line TF-1 that is responsive to granulocyte- macrophage colony-stimulating factor, interleukin-3, and EPO. In addition, the kinase activity of p92c-fes was shown to be enhanced by treatment with EPO. Therefore, p92c-fes could be implicated in a signaling pathway triggered by EPO in human EPO-responsive cells.

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