Field of Science

Lab Rat Working

Holidays are over :(
Image from here

I did not do the drawing, I hasten to add, but I do feel a bit like that. Sitting on top of seemingly impossible problems with a 'help meeee' sort of look.

At the moment I have decided to concentrate on revision because I am too tired (read lazy) to write my long essay. As my lever-arch file that contains the lecture notes is teetering on the brink of exploding, I've brought a book to write the revision notes in. So far I've filled in approximately half a page of it (NOT GOOD) but hopefully as it is a book rather than bits of paper I can do a NaNoWriMo thingy and try to fill up two pages a day.

Rather than, say, looking for pictures of rats on deviantart. heh.

Interesting Fact Of The Day: As there is now a large database of protein structures, many new structures can be determined by just looking at a DNA or protein structure and comparing it to the ones in the database. If you have the protein structure, you can also look at the individual amino-acids (the molecular building blocks that make up proteins) and using the knowledge of what kind of amino-acids they are (attracted to water, attracted to each other, acidic, polar, etc) make a reasonable guess as to the function.

This is one of those wonderful examples where science is very similar to trying to guess what the picture is on a half finished jigsaw puzzle (without looking at the box. In science there is no box). The more different techniques you use, the better you'll have an understanding of what the protein is, and of course some proteins are a lot easier to guess than others. A protein from a rat (say) with the exact same genetic code as a ribosome protein in a silverfish is easy. Another protein might have sections similar to the silverfish, but other bits that are more like bacterial membrane transporters, in whicch case you'll need a whole barrage of other techniques to figure it out.

Although if your DNA code is wrong to start with; due to contamination, procedural error, crossed communication wires or laziness, none of the fancy computer techniques will give any meaningful result. Nor will any of your experimental work, if you're recreated the protein from the genetic code you've been given.

And this does happen. There was a protein that developmental scientists were looking at a while back where (through no fault of the experimenter) the DNA mutated mid way through the growth-and-extraction process, which meant that everyone who was working on it (trying to find out where it migrated to in developing frog eggs) was working on a protein that didn't exist. Only one amino acid had changed, but it meant that this protein didn't migrate anywhere and all the researchers and poor little phD students were tearing their hair out about it.

Until someone finally decided to go back and check the sequence, essentially go through the whole tedious growing-frogs-and-taking-out-their-DNA-and-getting-the-right-bit-out all over again. They found that the bit of DNA they got the second time around was different to the one everyone else was working on. After that I think they did a couple more checks (well ... I hope they did. To be honest I wouldn't be surprised if they didn't) just to make sure they really had the right stuff, and yay! it migrated and some people wrote some papers and were happy about it.

Quick question: How long was the interval between the first attempt to get the correct DNA sequence and the second?

Answer: 20 years.

Oooops :)

To be fair to the scientific establishment though, there is a good reason for that. Science works on funding, and you just don't get funding for something that has Been Done Before. Another thing science works on is papers. The more papers you write, the more likely you are to get more jobs (and more funding) and you wouldn't realistically be able to publish a paper that just confirms someone else's work, not unless the work in question is starting to look very dodgy, and really needs conformation.

To be ever fairer to the scientists (especially as I am one), those twenty years working with the wrong protein were probably not an entire waste of time. They would have generated a lot of new techniques, and probably several people who were really good at tracking proteins by the end of it.

heh. still funny though. 20 years of the wrong thing...








Image from here

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