Well, it’s 2010. May it be better than 2009, probably one of the most miserable years I’ve ever experienced. Although, at least one good thing happened in 2009 – I joined the Delaware Liberal community. Thanks for giving me the opportunity, although I must be responsible for the lame-ification that anonone talks about. 🙁
Anyway, here’s an interesting science story to start out your year. Prions, proteins that contain no DNA, evolve. I’m not sure if this is comforting or extremely scary.
Jiali Li from the Scripps Institute in Florida has found that prions – the infectious proteins behind mad cow disease, CJD and kuru – are capable of Darwinian evolution, all without a single strand of DNA or its sister molecule RNA.
Prions are rogue version of a protein called PrP. Like all proteins, they are made up of chains of amino acids that fold into a complex three-dimensional structure. Prions are versions of PrP that have folded incorrectly and this misfolded form, called PrPSc, is social, evangelical and murderous. It converts normal prion proteins into a likeness of its abnormal self, and it rapidly gathers together in large clumps that damage and kill surrounding tissues.
Li has found that variation can creep into populations of initially identical prions. Their amino acid sequence stays the same but their already abnormal structures become increasingly twisted. These “mutant” forms have varying degrees of success in different environments. Some do well in brain tissue; others thrive in other types of cell. In each case, natural selection culls the least successful ones. The survivors pass on their structure to the “next generation”, by altering the folds of normal prion proteins.
This process follows the principles of Darwinian evolution, the same principles that shape the genetic material of viruses, bacteria and other living things. In DNA, mutations manifest as changes in the bases that line the famous double helix. In prions, mutations are essentially different styles of molecular origami. In both cases, they are selectively inherited and they can lead to adaptations such as drug resistance. In prions, it happens in the absence of any genetic material.
Prions are not considered living organisms, since they can’t reproduce on their own. I think this just shows that adaptation to one’s environment is a fundamental concept on Earth.
Conservative bloggers embarrass themselves again with the White House visitor’s list and with their ACORN obsession.
Far-right activists thought they’d hit the mother lode when they started going through the list of names. The Weekly Standard’s Michael Goldfarb proclaimed, “I tried to warn you, America. Rev. Wright and Bill Ayers!”
What conservatives didn’t realize is that, from time to time, different people have the same name. Yes, someone named William Ayers visited the White House this year, but not that William Ayers. Someone named Jeremiah Wright stopped by, but not that Jeremiah Wright. Michael Jordan and Michael Moore stopped by, but not the ones you know. Conservatives got excited for nothing.
And this week, they did it again. A far-right site discovered that Bertha Lewis was in the White House, just days before an ACORN controversy became national news. The site realized the possibility that there could be more than one Bertha Lewis, but nevertheless felt confident that they’d stumbled upon an important White House/ACORN nexis. The item’s headline didn’t leave room for ambiguity: “White House Visitors Log: ACORN CEO Bertha Lewis In Obama Residence Week Before Sting Videos Launched.”
It turns out it was just some woman named Bertha Lewis (she even had a different middle initial) that had visited the White House. You would think that after having been wrong last time they would have tried something like fact-checking this time. Fact-checking is for suckers!