Scientists at the University of California, Berkeley, have performed an in-depth analysis of DNA methylation in 17 species. The role of DNA methylation has been debated for years, but it is know to be important for regulation of many cellular events. The interesting aspect of DNA methylation is that it isn’t in all organisms– a lot, but it’s not present in budding yeast, flies, and even some worms. The researchers decided the best way to analyze this would be to create maps of methylation in all of the studied organisms. One of the first realizations is that some active genes are methylated, going against previous beliefs. Methylation is still seen to follow those original ideas in most organisms, but invertebrates seemed to reveal the opposite: not only were transposons (or jumping “parasitic” genes, usually from viruses or other foreign DNA) stuffed with methyl groups, but also the genes being used. The lab proposed that this was simply a remnant of ancestral enzymes and somehow the vertebrates re-evolved the long-lost mechanism.
Read More at Nature