Mammalian telomeres end in a large duplex loop
Article Abstract:
Electron microscopy analysis was performed on human and mouse cell's psoralen cross-linked telomeric DNA to investigate the structure of mammalian telomeres. Findings show the presence of large T loops with a size distribution consistent to their telomeric origin. This was found to be induced by the invasion of 3' telomeric overhang into the duplex telomeric repeat array. It was also revealed that T loops is partly responsible for the protection fn replication of telomeres.
Publication Name: Cell
Subject: Biological sciences
ISSN: 0092-8674
Year: 1999
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Three-dimensional structure of E. coli core RNA polymerase: promoter binding and elongation conformations of the enzyme
Article Abstract:
Electron microscopy of helical crystals shows that the Escherichia coli core RNA polymerase (RNAP) possesses a three-dimensional structure which is different from the structure of the holoenzyme. However, The RNAP is similar to yeast RNAPII. The core of the enzyme and yeast RNAPII has a thumb-like projection surrounding a open channel of 25 angstrom diameter. The open groove enables the identification and loading of promoter binding sites on the double-stranded DNA.
Publication Name: Cell
Subject: Biological sciences
ISSN: 0092-8674
Year: 1995
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Transcytosis and surface presentation of IL-8 by venular endothelial cells
Article Abstract:
There is evidence of chemokine involvement in actuating inflammatory leukocyte emigration, traversing the endothelial cells (ECs). This was believed to be achieved by chemokine diffusion through intercellular gaps. However the prototype chemokine IL-8 was shown, through electron microscopy, to be internalized by venular ECs to the luminal surface, and presented to leukocytes on the EC membrane.
Publication Name: Cell
Subject: Biological sciences
ISSN: 0092-8674
Year: 1997
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