Thread: Baffled.
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Old September 10, 2015   #16
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Join Date: Jan 2006
Location: Upstate NY, zone 4b/5a
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Originally Posted by frogsleap farm View Post
Methylation of gene promoters or coding sequences is a common method of gene silencing and can be under genetic and/or epigenetic control. This is one of several mechanisms in how plants/animal/microbes manage gene expression. As you know, this is an exciting and emerging field in biology/genetics. The roles of micro-RNAs and transcription factors in regulating individual genes and/or whole metabolic pathways is now probably better understood in humans than in plants - but the principles are very similar. Rin is a classic transcription factor that regulates, directly or indirectly, several different processes in tomato fruit - together controlling the fruit ripening process. Methylation/silencing of specific genes may be involved - but not sure. The recessive loss-of-function mutant "rin" results in a non-ripening phenotype, as does alc/alc, but as noted in the photos above there are other phenotypic traits that are quite different between these two mutants - thus my interest.
I'm glad I did bring up the subject of DNA methylation as a transcription controller b/c now I know more about rin and for sure there will be more information in the future,'

But it got me thinking about the variety Lutescent, nee Honor Bright:

Notice under traits that it's considered a longkeeper and the thinking is that there was a single pleiotropic mutation that affected many other genes at the same time that led to the many changes in leaf color and transition of different colored fruits as part of the ripening process. Maybe Google IMAGES shows that

Yes, I've grown it and the final red fruits are NOT good tasting at all.

There are other tomatoes also known as lonngkeepers but I don't think anyone has done anything with them biochemically

I suppose my own DNA is also methylated and if so I know which of my genes I'd like shut off and also some that I'd like activated.

As it is, I've been saying for a couple of years that I want to participate in the National Geographic Genome Project. You pay your money, not cheap, and are sent a kit for you to take saliva swabs and send them in. Not for medical reasons, rather to find out which percentage of your DNA corresponds to which area on earth, whether Northern European, Micronesia, African, etc. And going back thousands of years to early man, denisovan, and whatever and I really should do that,

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