Chicken Erythrocyte Histone Octamer Preparation

Abstract OBJECTIVEHistones and resulting nucleosomes occur within DNA regulating gene expression by slowing, pausing, or halting transcriptional machinery. Positions within the genome have been found with higher affinity for the histone octamer than others. Histone/nucleosome repositioning is adjusted via energy dependent remodeling complexes, and a harmonizing array of constellation proteins and molecules. The energy required to create transcriptional environments is created through oxygen intake, nutrient presence, and extracellular movement. In this paper we aim to help facilitate an in silico framework for further experimentation into how partial pressures of oxygen and other gases impact genetic transcription along with extracellular movement and nutrient delivery.RESULTSCell and tissue culture experimentation with biomechanical strain and variable partial pressures of oxygen and other gases can be made into the expression levels of genes such as PH domain leucine-rich repeat-containing protein phosphatase 1 (PHLPP1), and Neuroligin 1 (NLGN1). These genes show in silico to have a higher affinity for a histone octamer binding motif, needing adequate cellular energy to be expressed. Extracellular movement and adequate cellular oxygenation are required to properly reposition nucleosome sequences for transcription.

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Probing the free space within rat and chicken chromatin with active and passive probes

Journal of Cell Science ◽

10.1242/jcs.37.1.85 ◽

1979 ◽

Vol 37 (1) ◽

pp. 85-96

Author(s):

L.A. Burgoyne ◽

J.D. Skinner

Keyword(s):

Rat Liver ◽

Free Space ◽

Chicken Erythrocyte ◽

Rat Liver Nuclei ◽

Liver Nuclei ◽

Chicken Erythrocytes

The cavity systems within chicken erythrocyte nuclei and rat liver nuclei were compared using passive probes of radioactive glycogen and active probes of nuclease-armed-glycogen. The passive probe curves have a form that indicates that they are due to passive occupation of spaces and not due to the effects of a limiting membrane. The technique of probing nuclei with glycogen armed with a small enzyme is described. The chicken erythrocytes appeared to have 11–15-nm and 4–5-nm cacity systems similar to those we have previously reported in rat nuclei. Evidence is presented to show that the bridge DNA is enclosed within the 4–5 nm cavities in both rat liver and chicken erythrocyte nuclei. Minor differences between the rat liver and chicken erythrocyte nuclear cavity systems are noted in the region of 5–8 nm. A relatively mild procedure is described for preparing chicken erythrocyte nuclei.

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Characterizing Circulating Nucleosomes in the Plasma of Dogs with Lymphoma

10.21203/rs.3.rs-318227/v1 ◽

2021 ◽

Author(s):

Christopher Dolan ◽

Tasha Miller ◽

Jarvis Jill ◽

Jason Terrell ◽

Theresa Kelly ◽

...

Keyword(s):

Fold Increase ◽

Monitoring Tool ◽

Treatment Results ◽

Canine Lymphoma ◽

Histone Octamer ◽

Objective Monitoring ◽

Remission Status ◽

T Cell Lymphomas ◽

Healthy Dogs ◽

Multicentric Lymphoma

Abstract Background: Nucleosomes consist of DNA wrapped around a histone octamer core like beads on a string so that DNA can be condensed as chromatin into chromosomes. Diseases such as cancer or inflammation lead to cell death where chromatin is fragmentated and released as mononucleosomes into the blood. The Nu.QTM H3.1 assay measures total nucleosome concentration in plasma of humans and has been used to detect and identify cancer even at early stages. The objectives of this study were to determine if nucleosome levels could be used to distinguish between healthy dogs and dogs with various stages of lymphoma (LSA) using the Nu.Q™ H3.1 assay. A total of 126 dogs diagnosed with LSA and 134 healthy controls were recruited for this study. Plasma was collected from each dog and stored in K2-EDTA tubes. The LSA patient samples were recruited from TAMU or purchased from various biobanks. All control cases were recruited from TAMU. Samples were also collected longitudinally from 3 dogs undergoing treatment for multicentric lymphoma at TAMU as a pilot study to investigate the pattern of nucleosome concentrations in plasma during treatment. Results: Dogs with LSA had an approximately 7-fold increase in their plasma nucleosome concentrations compared to controls (AUC 87.8%). Nucleosome concentrations increased with cancer stage and dogs with B cell lymphomas had significantly higher nucleosome concentrations than dogs with T cell lymphomas. Nucleosome concentrations from serially monitored patients were elevated at diagnosis and progression with subsequent decreases in nucleosome concentration that corresponded to clinically detectable responses to therapy. Conclusions: The Nu.QTM H3.1 assay was able to reliably detect elevated nucleosome concentrations in the plasma of dogs with LSA. Furthermore, it appears that nucleosomes are useful for differentiating cancer from healthy individuals in canines. Results from serially monitored patients indicate that nucleosomes could be an objective monitoring tool for remission status in canine lymphoma patients.

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