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:3/17/2016)... 17, 2016 ABI Research, the leader ... global biometrics market will reach more than $30 ... from 2015. Consumer electronics, particularly smartphones, continue to ... anticipated to reach two billion shipments by 2021 ... Pavlakis , Research Analyst at ABI Research. "Surveillance ...
(Date:3/14/2016)... , March 14, 2016 NXTD ) ... mobile commerce market, announces the airing of a new series ... the week of March 21 st .  The commercials will ... its popular Squawk on the Street show. --> ... the growing mobile commerce market, announces the airing of a ...
(Date:3/11/2016)... --> --> ... Recognition Market by Technology (Pattern Recognition), by Component (Hardware, ... Type (On-Premises and Cloud), by Industry Vertical and by ... the global market is expected to grow from USD ... 2020, at a CAGR of 19.1%. , ...
Breaking Biology News(10 mins):
(Date:5/4/2016)... ... 05, 2016 , ... CereScan, the nation’s leader in providing ... National Stroke Awareness Month in May. An infographic created by CereScan will ... CereScan will donate $1 up to a maximum of $3,000 through users who ...
(Date:5/4/2016)... NY (PRWEB) , ... May 04, 2016 , ... The ... a genetic disorder that causes tumors to grow on nerves throughout the body. It ... cure. , Through numerous community events held during the month of May, as well ...
(Date:5/3/2016)... PUNE, India , May 3, 2016 ... Type (DNA Chip (Genomics, Drug Discovery, Gene ... Chips), End user (Academics Institutes, Diagnostics Centers), ... 2020" published by MarketsandMarkets, the market is ... 2020 from USD 7.63 Billion in 2015, ...
(Date:5/3/2016)... ... May 03, 2016 , ... Flagship Biosciences, the ... Gillett to its Board of Directors. Dr. Gillett recently retired from Charles River ... President and Chief Scientific Officer. A board-certified veterinary pathologist, Dr. Gillett joined Charles ...
Breaking Biology Technology:
Cached News: