HOME >> BIOLOGY >> NEWS
Ancient defense mechanism may still be protecting us

to the next until a "safe to use" set of genes remain to be given to the cell's offspring.

Nearly all cells house their DNA inside a nucleus, but Tetrahymena houses different versions of its DNA in each of its two nuclei. The smaller nucleus (called the micronucleus) does nothing more than keep the cell's full genome safe, acting as a sort of "lock box." The larger nucleus (called the macronucleus), on the other hand, uses the DNA to regulate the cell's life functions. This macronucleus houses about 15 percent fewer DNA sequences than the smaller one, and when the cell mates to create a new generation of cells, this large macronucleus withers and dies. Before it completely expires, however, the small nucleus steps in and produces a new large and small nucleus set. To make sure no new viral sequences have sneaked into the lock box, the cell checks the DNA of the small, lock box nucleus against the DNA of the old large nucleus and eliminates any foreign material before allowing the new large nucleus to develop.

Gorovsky's team believes that in evolutionarily ancient times, cells had to fight against a variety of assaults just as they must today: viruses attacked cells, injecting their DNA, disrupting normal cell functions; and transposons, bits of nomadic genetic material, would fit themselves in several places in the cell's genome, copying themselves prodigiously and wreaking havoc. To survive, cells evolved a correction system that recognized the invading DNA and either eliminated or silenced it. Gorovsky and Mochizuki propose that the small nucleus "transcribes" into RNA part or all of its DNA, essentially making RNA photocopies of certain DNA sections. These transcriptions include the sections that may have been corrupted by some genetic marauder like a virus or transposon. The transcribed RNAs then migrate out of the small nucleus, through the cell to the large nucleus where they mingle with the macronucleus' DNA. If an RNA comes across a section
'"/>

Contact: Jonathan Sherwood
Jonathan.Sherwood@rochester.edu
585-273-4726
University of Rochester
17-Oct-2002


Page: 1 2 3

Related biology news :

1. Ancient life form may help create newest technologies
2. Ancient brewery discovered on mountaintop in Peru
3. Ancient Greeks help scientists build environmentally friendly nano devices
4. Ancient DNA mutations permitted humans to adapt to colder climates, UCI researchers find
5. Ancient Inca road in desperate need of protection
6. Ancient DNA analysis unveils mystery of historys most horribly deformed man -- The Elephant Man
7. Ancient pollen yields insight into forest biodiversity
8. Ancient flower fossil points to underwater origins
9. Ancient supernova may have triggered eco-catastrophe
10. Ancient Chinese folk remedy may hold key to non-toxic cancer treatment
11. Ancient reptile is efficient chewer

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:6/2/2016)... 2016 Perimeter Surveillance & Detection ... Physical Infrastructure, Support & Other Service  The ... offers comprehensive analysis of the global Border Security ... revenues of $17.98 billion in 2016. Now: ... leader in software and hardware technologies for advanced video ...
(Date:5/12/2016)... May 12, 2016 WearablesResearch.com , a ... the overview results from the Q1 wave of its ... wave was consumers, receptivity to a program where they ... a health insurance company. "We were surprised ... says Michael LaColla , CEO of Troubadour Research, ...
(Date:4/26/2016)... and LONDON , ... Finacle, part of EdgeVerve Systems, a product subsidiary ... Onegini today announced a partnership to integrate the ...      (Logo: http://photos.prnewswire.com/prnh/20151104/283829LOGO ) ... provide their customers enhanced security to access and ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... Mosio, a leader in ... Trials Patient Recruitment and Retention Tips.” Partnering with experienced clinical research professionals, Mosio ... practical tips, tools, and strategies for clinical researchers. , “The landscape of how ...
(Date:6/23/2016)... SPRING, Md. , June 23, 2016 A ... collected from the crime scene to track the criminal down. ... and the U.S. Food and Drug Administration (FDA) uses DNA ... Sound far-fetched? It,s not. The ... genome sequencing to support investigations of foodborne illnesses. Put as ...
(Date:6/23/2016)... 2016  The Biodesign Challenge (BDC), a university competition ... harness living systems and biotechnology, announced its winning teams ... New York City . The ... projects at MoMA,s Celeste Bartos Theater during the daylong ... senior curator of architecture and design, and Suzanne ...
(Date:6/23/2016)... ... ... In a new case report published today in STEM CELLS Translational Medicine, doctors ... being treated for breast cancer benefitted from an injection of stem cells derived from ... frequent side effect of cancer treatment. , Lymphedema refers to the swelling ...
Breaking Biology Technology:
Cached News: