(Before It's News)
Most of us store all kinds of junk in our garages and basements because we think that it might be useful at some time in the future. One day, we convince ourselves, we will dig out those old cleats or need that widget. Then the time comes for a good spring cleaning, and we declare that much of the junk we’ve been saving is just garbage and put it out on the curb for pick-up.
Much like basements, genomes are full of junk (such as repetitive sequences of DNA that have no obvious function). Of course, genomes also encode the instructions for making essential mRNA molecules and proteins, and these instructions need to be passed on to future generations. Many eukaryotes separate out these activities. For example, multicellular plants and animals use different cell types: the main “somatic” cells of the body express genes, while germline cells (such as egg and sperm cells) propagate DNA to offspring. Single-celled eukaryotes called ciliates, on the other hand, keep their germline genome in a germline micronucleus and their somatic genome in a separate somatic macronucleus. Now, in eLife, Robert Coyne of the J. Craig Venter Institute and colleagues – including Eileen Hamilton and Aurélie Kapusta as joint first authors – report that they have sequenced the germline genome of a ciliate called Tetrahymena thermophila
(Hamilton et al., 2016
@ One genome’s junk is another’s garbage | eLife: