Publications by authors named "Esmat Hegazi"

Understanding the molecular mechanisms underlying chromatin regulation, the complexity of which seems to deepen with each passing year, requires a multidisciplinary approach. While many different tools have been brought to bear in this area, here we focus on those that have emerged from the field of chemical biology. We discuss methods that allow the generation of what is now commonly referred to as "designer chromatin," a term that was coined by the late C.

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Article Synopsis
  • Amplification of MDM2 on extra chromosomes is a frequent way tumors inactivate the P53 protein, which is crucial for controlling cell growth and preventing cancer.
  • In dedifferentiated liposarcoma, MDM2 overexpression affects gene regulation and cell characteristics through three main regulatory circuits and interacts with other transcription factors.
  • There is significant variability in MDM2 levels within tumor cells, and while most liposarcoma cells respond to MDM2 inhibitors combined with pro-apoptotic drugs, those with high MDM2 levels tend to resist these treatments, leading to poor clinical outcomes.
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Background: The cotton leafworm, Spodoptera littoralis, is a highly polyphagous pest of many cultivated plants and crops in Africa and Europe. The genome of this pest will help us to further understand the molecular mechanisms of polyphagy.

Results: Herein, the high-quality genome of S.

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Understanding reproduction is essential for controlling pests and supporting beneficial insects. Among the many factors allowing optimal reproduction, sperm availability is key to sex ratio control in hymenopteran parasitoids since males are haploid and only females come from fertilization. (Hymenoptera; Braconidae) is a solitary endoparasitoid of some noctuids.

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Widespread changes to DNA methylation and chromatin are well documented in cancer, but the fate of higher-order chromosomal structure remains obscure. Here we integrated topological maps for colon tumors and normal colons with epigenetic, transcriptional, and imaging data to characterize alterations to chromatin loops, topologically associated domains, and large-scale compartments. We found that spatial partitioning of the open and closed genome compartments is profoundly compromised in tumors.

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Epigenetic aberrations are widespread in cancer, yet the underlying mechanisms and causality remain poorly understood. A subset of gastrointestinal stromal tumours (GISTs) lack canonical kinase mutations but instead have succinate dehydrogenase (SDH) deficiency and global DNA hyper-methylation. Here, we associate this hyper-methylation with changes in genome topology that activate oncogenic programs.

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The red palm weevil, Rhynocophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) has become the most important pest of the date palm trees in the world. It has been reported in the kingdom of Saudi Arabia since 1987 and in Egypt since 1992. Studies were conducted to compare preferences among red palm weevil life stages for infection by 12 entomopathogenic nematodes (EPNs), under no choice and five stage choice experiments, and curative trials by some of EPNs isolates.

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Entomopathogenic nematodes are generally considered beneficial organisms. However, they can affect beneficial insects such as parasitoids. The interaction between the entomopathogenic nematodes Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae) and Steinernema carpocapsae Weiser, and the parasitoid Microplitis rufiventris Kokujev (Hymenoptera: Braconidae) was investigated in the laboratory.

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To study the dynamics of stage-dependent immune responses in Spodoptera littoralis (Boisd.) larvae (Lepidoptera: Noctuidae), single and superparasitism experiments were carried out using the parasitoid Microplitis rufiventris Kok. (Braconidae: Hymenoptera).

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Relative effects of parasitism by Microplitis rufiventris on the development of the third instar Spodoptera littoralis (preferable, optimal host) with the development of penultimate (5th) and last (6th) instars (suboptimal hosts) were investigated. Newly molted 6th instar hosts were more acceptable for parasitization by the wasp female than older hosts. In singly parasitized 3rd instar hosts, 82.

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We compared the production of pseudoparasitization by Microplitis rufiventris females in most (third) and less (fourth) preferred instars of Spodoptera littoralis larvae at 20+/-1 and 27+/-1 degrees C. The parasitized hosts were classified into hosts producing parasitoids (type A hosts) and hosts producing no parasitoids, i.e.

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