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Latest RNA polymerase I Stories

2012-07-20 01:50:16

New research has shown that a protein does something that scientists once thought impossible: It unfolds itself and refolds into a completely new shape. This protein, called RfaH, activates genes that allow bacterial cells to launch a successful attack on their host, causing disease. The researchers determined that RfaH starts out in its alpha form, composed of two spiral shapes. Later, in its beta form, it resembles spokes on a wheel and is called a barrel. When RfaH refolds, it...

2011-07-15 14:16:31

Successful gene expression requires the concerted action of a host of regulatory factors. Long overshadowed by bonafide transcription factors, coactivators"”the hanger-ons that facilitate transcription by docking onto transcription factors or modifying chromatin"”have recently come to the fore. In their latest study, published in the July 15, 2011, issue of Genes & Development, researchers at the Stowers Institute for Medical Research discovered that the highly conserved...

2011-07-07 20:26:11

Look up "transcription""”the copying of a gene's DNA into RNA intermediaries"”in any old molecular biology text book, and it all seems very simple: RNA polymerase II, the enzyme that catalyzes the reaction, assembles at the start site and starts motoring down the strand, cranking out the RNA ribbon used to construct proteins. But researchers now know that RNA polymerase II often stalls on DNA strands where it was once assumed to just barrel down. A report from the Conaway lab at...

2011-02-23 17:39:19

How the cell deals with transcriptional roadblocks Gene transcription is central to cell function, as it converts the information stored in the DNA into RNA molecules of defined sequence, which then program protein synthesis. The enzyme RNA polymerase II (Pol II) is responsible for this genetic readout, but is prone to transcriptional arrest. The biochemist Professor Patrick Cramer, Director of LMU's Genzentrum, and his research associate Dr. Alan Cheung have now shown for the first time...

2010-08-20 14:01:56

Physical model describes the distribution of nucleosomes The DNA genomes of organisms whose cells possess nuclei are packaged in a highly characteristic fashion. Most of the DNA is tightly wrapped around protein particles called nucleosomes, which are connected to each other by flexible DNA segments, like pearls on a necklace. This arrangement plays a major role in deciding which genes are actively expressed, and thus which proteins can be synthesized in a given cell. The LMU Munich...

2010-01-07 18:03:35

Plants are incredibly temperature sensitive and can perceive changes of as little as one degree Celsius. Now, a report in the January 8th issue of the journal Cell, a Cell Press publication, shows how they not only 'feel' the temperature rise, but also coordinate an appropriate response -- activating hundreds of genes and deactivating others; it turns out it's all about the way that their DNA is packaged. The findings may help to explain how plants will respond in the face of climate change...

2009-10-10 07:42:26

All cells perform certain basic functions. Each must selectively transcribe parts of the DNA that makes up its genome into RNAs that specify the structure of proteins. The set of proteins synthesized by a cell in turn determines its structure and behavior, and enables it to survive and reproduce. So it is crucial that the appropriate stretches of DNA are transcribed in each cell type. In the Oct. 9 issue of the journal Nature, a team of researchers at the Gene Center of...

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2009-07-30 13:45:54

The body's nanomachines that read our genes don't run as smoothly as previously thought, according to a new study by University of California, Berkeley, scientists.When these nanoscale protein machines encounter obstacles as they move along the DNA, they stall, often for minutes, and even backtrack as they transcribe DNA that is tightly wound to fit inside the cell's nucleus.The findings come from delicate measurements of molecular-scale forces exerted on individual proteins that move along...


Word of the Day
abrosia
  • Wasting away as a result of abstinence from food.
The word 'abrosia' comes from a Greek roots meaning 'not' and 'eating'.