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:
TAG: Ancient defense mechanism may still protecting

(Date:4/17/2014)... German . ... also provide us with a continuous stream of information about ... sit still in a car the world glides by ... Seemingly without effort, our brain calculates self-motion from this "optic ... a steady gaze during our own movements. Together with biologists ...
(Date:4/17/2014)... House honored Clemson professor Rajendra Singh Thursday as ... promote and expand solar deployment in the residential, ... Houser Banks Professor of Electrical and Computer Engineering ... is considered a local hero leading the charge ... opportunity in solar power and driving policy changes ...
(Date:4/17/2014)... hit on a novel method to help kidney ... most effective treatment possible., Kidney stones represent a ... world. If left untreated, apart from being particularly ... other complications. In many patients treated successfully, stone ... effective pathological approach to diagnosis and treatment needs ...
Breaking Biology News(10 mins):How vision makes sure that little fish do not get carried away 2How vision makes sure that little fish do not get carried away 3How vision makes sure that little fish do not get carried away 4White House honors Clemson professor as 'Champion of Change' for solar deployment 2
(Date:1/15/2014)... (PRWEB) January 15, 2014 DTS Language ... its Online Web Portal for Life Science organizations who need ... specify the subject matter of their documents in advance with ... help reduce time-to-delivery of translations, often a critical factor in ...
(Date:1/15/2014)... AudioNotch is the internet's leading provider of Notched Sound ... Patients listen to sound therapy that is tailor-made for ... to months, their tinnitus volume decreases. , AudioNotch has previously ... Notched White Noise. Now, AudioNotch is pleased to announce to ...
(Date:1/14/2014)... Washington, DC (PRWEB) January 14, 2014 ... session for Thursday, January 23, 2014 at 2pm EST ... Actionable Knowledge.” The topic focuses on how technology can ... mission critical decisions for government agencies. The online webinar ...
(Date:1/14/2014)... 2014 As pet owners drew up their lists of New ... "Take better care of my furry companion." Nowadays there are pet ... carrying cases to take the little canine or feline darlings along ... to buy some pricey toys at the pet store. But anyone ...
Breaking Biology Technology:DTS Improves Efficiency for Life Science Document Translations 2Webcast - Natural Language Processing: Converting Raw Data into Actionable Knowledge – Hosted by Carahsoft and CDS Federal Services 2New Year's Resolution: Give Pets the Gift of Top-Notch Health Care 2
Cached News: