I’ve updated yesterday’s post on the “dark matter” of the genome with replies from a co-author of the paper I wrote about.
Originally published June 22, 2013. Copyright 2013 Carl Zimmer.
One of the great triumphs of twentieth-century biology was the discovery of how genes make proteins. Genes are encoded in DNA. To turn the sequence of a gene into a protein, a number of molecules gather around it. Reading its sequence, they produce a single-stranded version of it made of RNA, called a transcript. The transcript gets shipped to a cluster of other molecules, the ribosome, which picks out building blocks to construct a protein that corresponds to the gene. The protein floats off to do its job, whether that job is to catch light, digest food, or help generate a thought.
We have about 20,000 protein-coding genes. If you tally up the amount of DNA they constitute, you get less than 3 percent of the human genome. Which naturally raises the question of what’s in the other 97 percent.
At this weekend’s Cancer and Evolution meeting, one of the highlights was a talk from a husband-and-wife team of biologists at Rochester University about naked mole rats. As far as scientists can tell, naked mole rats don’t get cancer, despite living up to 30 years. That’s pretty remarkable when you consider that another rodent–the lab mouse–has a 47% cancer rate during its brief, two-year life.
So a number of researchers have been searching the biology of naked mole rats for their secret. The Rochester scientists may have found a crucial ingredient in their cancer defense. And, by happy coincidence, Nature is publishing their report today. That’s the subject of my “Matter” column this week. Check it out.
Originally published June 19, 2013. Copyright 2013 Carl Zimmer.
The New York Times, June 19, 2013
The laboratory of Vera Gorbunova and Andrei Seluanov, a husband-and-wife team of biologists at the University of Rochester, has the feel of a petting zoo. They maintain colonies of several species of rodents — some familiar, like mice and guinea pigs, and some much more exotic, like blind mole rats from Israel and naked mole rats from East Africa.
Amusing children with furry creatures is not their goal, however. The biology of animals is mysteriously diverse, and lurking within it may be clues to new kinds of medicine.
Continue reading “A Homely Rodent May Hold Cancer-Fighting Clues”
Millions of years ago, some bats gave up their old habits of hunting for insects and tried something new: drinking blood. These creatures evolved into today’s vampire bats, and it’s mind-boggling to explore all the ways that they evolved to make the most of their sanguine meal.
A lot of the adaptations are easy enough to see with the naked eye. Vampire bats have Dracula-style teeth, for example, which they use to puncture the tough hide of cows. When they open up a crater-shaped wound, they dip in their long tongue, which contains two straw-shaped ducts that take up the blood. Continue reading “Dracula’s Children”