Backup DNA
Posted 23 Mar, 2005 at 10:54 by wendy in /Science | Permanent link
I found this on BoingBoing this morning, scientists have discovered that some plants appear to have "backup DNA", the mutated part of the DNA they received from their parents had been overwritten by DNA from their grandparents, apparently stored somewhere as RNA. Link
Comments (6 comments so far)
Very interesting article.
Reminds me of some reading I did about polyploid species, and how they increase as you head towards the artic. One theory on why was that the effects of solar radiation etc, were more strongly felt up there and there was a greater risk of mutation. The extra chromosomes acted as a safeguard. One or even two chromosomes in a cell could be damaged, but the plant would still have two from which to replicate.
In short, plant life seems to have evolved far beyond us mere mortals in terms of it's ability to adapt to a hostile, mutatious, enviroment.
Posted 2005/3/24 04:50:45 by
Blue
That might well be because we've evolved useful traits like mobility so that we can leave hostile, mutatious (?) environments. Plants just followed a different route. Saying that they're beyond us is like saying that insects are beyond us because lots of them can fly and we're stuck on the ground.
Posted 2005/3/24 05:29:04 by
matt
I would argue that plants are also mortal... ;)
Posted 2005/3/24 11:57:47 by
wendy
Less so than humans in many ways though... outside of the fact that many live far longer than us, and in some cases, seeds from trees last millenia (there is one great record of an extinct type of tree in Japan that was resurrected after seeds were found in an archeological dig). And, in some specific cases, there is an arguement that the plant has a continuous life (different leaves, but same perpetual root system, growning and dieing), that short of catastrophy, it is the *same* plant... forever.
Then again... not being able to play ultimate would be a pain... so I'll suffer my mortal existance for now ;)
Posted 2005/3/24 14:04:52 by
blue
Scientific American had an article on alternative splicing where a single "gene" of exons and introns can map to multiple proteins due to alternate ways of interpreting when to splice out introns or exons from the sequence. Which is why our some 25,000 genes can map to over 90,000 proteins.
The article provides an interesting vector for additional redundancy, but I'm curious how that redundancy is managed, does the DNA affect the RNA? How would the RNA replicate then for subsequent cells? It will probably take a significant amount of time to really dig out the details of the mechanism and reproduce the experiment in other laboratories to verify the existence of the phenomena.
Posted 2005/3/28 07:52:13 by
Brent
I believe it has something to do with what proteins are present in the cell when transcription is happening. Typically the DNA is transcribed into RNA, which gets spliced, and then forms a protein. Once the protein has been formed, the RNA is broken down and recycled. The splicing locations can be affected by the presence of proteins, random chance and probably other things. You can also affect exactly where the DNA transcription starts by playing around with what proteins are present. Biology these days is really cool.
Posted 2005/3/29 12:49:25 by
wendy