Article Abstract:
A framework was proposed in which the bending and wrapping of DNA around RNA polymerase promotes the untwisting of the DNA helix at the RNA polymerase catalytic center to stimulate the separation of strands prior to initiation. DNA bending through the RNA polymerase active site was proposed to minimize the energetic barrier to the advance of the transcription bubble. Results of studies with mammalian RNA polymerase II revealed the importance of DNA bending and wrapping in transcriptional mechanisms.
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Article Abstract:
Parasitic organisms can adapt as the environment is altered, and they can thus survive difficult conditions. The mechanisms can be studied through an examination of the helminthic and protozoic parasites. These mechanisms include signal transduction pathways, gene expression regulation, and organelle biogenesis. Giardia lamblia is especially interesting because it is an early eukaryote and is a key cause of enetric disease across the world. A stimulus has been found that causes cysts to develop.
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Article Abstract:
Virus transmission among plants is generally carried out when the needle-like mouthparts of vectors penetrate the cell wall of plants. These vectors, including arthropods, nematodes and fungi, feed on the plant by exerting a certain degree of mechanical force to pierce the plant's cell wall without damaging it. The virus is then carried in highly-motile zoospores which invade neighboring cells, thereby infecting them.
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