New Levels of Complexity Found in DNA and Space

The deeper we look, the more complex order we discover.

i-3cd0e5a0909890a8a6cd3e39c5a7d408-chromosome.jpgBiologists studying DNA have discovered another pattern of code within the genetic code. This pattern may regulate the placement of nucleosomes:

Biologists have suspected for years that some positions on the DNA, notably those where it bends most easily, might be more favorable for nucleosomes than others, but no overall pattern was apparent. Drs. Segal and Widom analyzed the sequence at some 200 sites in the yeast genome where nucleosomes are known to bind, and discovered that there is indeed a hidden pattern.

Knowing the pattern, they were able to predict the placement of about 50 percent of the nucleosomes in other organisms.

The pattern is a combination of sequences that makes it easier for the DNA to bend itself and wrap tightly around a nucleosome. But the pattern requires only some of the sequences to be present in each nucleosome binding site, so it is not obvious. The looseness of its requirements is presumably the reason it does not conflict with the genetic code, which also has a little bit of redundancy or wiggle room built into it. (via the New York Times)

Another way of looking at it: If chunks of genetic code are like pages in a recipe book, then the nucleosome code would be like the binding holding the pages in order. It makes me wonder how many other hidden patterns are holding together these tiny books of life.

Out in space, other hidden layers have been revealed this week, as Cassini captures radar images of extra-terrestrial lakes:

i-17c60bd302837290f8db0168bb4ee8b6-titan.jpg

(via NASA Planetary Photojournal)

Of course, these lakes, which appear near Titan's poles, are not filled with the crystal blue water that we are familiar with. Rather, these lakes are probably filled with a murky, brownish solution of liquid hydrocarbons. For this reason, I wouldn't expect these lakes to become some space tourist destination any time soon. These pools of ethane and methane probably make places like the Great Salt Lake or Hot Sulfur Springs smell nice in comparison.

Image notes: Chromosomes via Ceska, image of Titan via NASA Planetary Photojournal

More like this

"Everyone is a moon, and has a dark side which he never shows to anybody." -Mark Twain Back before the telescope was invented, Saturn was known as the Old Man of the Skies. The slowest-moving of the naked-eye planets, it's the only one that would reliably be in nearly the same location, year after…
But not that moon. Saturn's moon. And it is not really the Nile. But, just as the Nile is one of the longest rivers on Earth, this new river is the longest river observed anywhere other than the earth. Yay Earth, you have the Longest Rivers known to Earthlings! Scientists with NASA's Cassini…
A paper from a week or so, describes a method for detecting regions in the genome where DNA wrapping takes place. So what (you may asked) is DNA wrapped around? Nucleosomes! Each nucleosome (red balls in the cartoon) contains 8 histone proteins (two each of Histone 2A, 2B, 3 and 4). In addition,…
A key concept in science is molecular scale. DNA is a fascinating molecule in this regard. While we cannot "see" DNA molecules without the aid of advanced technology, a full length DNA molecule can be very long. In human cells, other than sperm and eggs, six billion base pairs of DNA are packaged…

The paper is both interesting and perplexing. I realize that 50% is actually quite better than it sounds on first approximation, but it is written in quite an obscure fashion and the figures are not very reader friendly. Their methodology though I think was the correct one.

These pools of ethane and methane probably make places like the Great Salt Lake or Hot Sulfur Springs smell nice in comparison.

Ethane and methane are both odorless in their pure form. . . The nasty smell associated with methane gas is put there intentionally: the gas company puts a sulfur-containing compound (say, ethyl mercaptan) into domestic gas so people can sniff leaks.

I wonder what the actual sulfur content of Titan beachfront property is?

Punko, I've only had a chance to glance at the paper, so I couldn't agree with you on the style, one way or the other.

Blake, I knew that... I suppose I was having one of those brain farts (which are also odorless?) I would be surprised if the brownish organic haze of Titan smelled unpleasant, though.