Month: July 2007

Francis Crick and the long-term storage of the memory trace

Since my Ph.D. is related to memory consolidation, I was interested in a strange idea from Francis Crick. He asked the question of long-term storage of the memory trace 1. How is this memory trace stored in our brain? And, more importantly, how is it protected against molecular turnover? In his view, Crick suggested three hypothesis:

  1. Memory could be encoded in alterations of some part of the cell DNA. This will imply that each neuron synapse would be represented by a part of the neuron DNA since the actual paradigm states that memory is encoded in the strength of individual synapse. This first hypothesis seems unlikely.
  2. Memory could otherwise be stored in a local piece of DNA or RNA, at the synapse (a bit like the mitochondrion has its own DNA). This piece would be immune to the molecular turnover. Although more logical, this hypothesis seems unlikely too.
  3. Finally, Crick’s last hypothesis states that molecules at the synapse level would interact in such a way they could be replaced by new ones, one at a time, without altering the general status (strength). The figure below shows a working example of this hypothesis …

In this figure, two monomers (squares) forms a hypothetical protein
highly involved in a memory process at the synapse level. Each monomer can be in two states: active (plus sign) or inactive (minus sign). Activation of the monomer could be done by phosphorylation (in this example ; any other modification could be applied here). The hypothetical protein can either be active (plus plus) or inactive. The key point in Crick’s hypothesis is an enzyme which will phosphorylate a monomer if the protein is in state (plus minus), giving an active (plus plus) protein, but not if it is in state (minus minus). This will counteract the molecular turnover which transform an active (plus plus) protein into an inactive (plus minus) one.

Of course, Crick’s hypothesis can be extended to proteins that are trimers, tetramers, … other process than phosphorylation could be used (methylation, glycosylation, …) and more conditions could also be added (anchoring, maturity, …).

What do you think of this hypothesis?

1 Crick F. “Neurobiology: Memory and molecular turnover” in Nature 312:101 (1984) – read the PDF

Belgian finance public service website :-(

I was looking for a simple info on the Belgian finance public service website: the address of their office in Liege. I know it’s rue Paradis but I also need opening hours and a general contact phone number. I can tell you this website is really crappy! First, when you arrive on the website, you are overwhelmed by links, info, text everywhere and, of course, the photo of the Finance minister. Now it will take you at least 30 seconds to know where to look. Then, it’s impossible to easily find an address ; I didn’t even find it at all! I tried their “search engine”: no result. Their site map takes ages to load (with no result, of course; it won’t be funny otherwise). When you try to click on most services on the left, you launch a new website, completely different from the main one (still no sign of the address). I guess they don’t want to be contacted …

Well, I don’t give up easily. I tried to send an e-mail to the portal contact address: (to ask for the info and tell them about the “user firendliness” of their website). Of course, this address is not usefull at all since I immediately got an anwser: “Delivery Notification: Delivery has failed”. What is more interesting is when you look for the reason (e-mail servers always include some details about errors) … “Diagnostic code: lmtp;522 5.2.0 Delivery failed: Over quota” (emphasis is mine). Two options: 1. they read e-mail citizens are sending but they are temporarily overwhelmed by e-mails -or- 2. they don’t care about citizens and don’t bother to read their e-mails. I think they don’t care about us: I guess no one is actually reading these e-mails and they are accumulating since a long time.

On some webpages, there is a “website coordinator” name: Françoise Gerckens. Of course, there is no e-mail, no form, nothing. It’s also interesting to read their disclaimer: they are not responsible for anything and people cannot complain about what’s there.

Finally, against my will, the old clichés about public administration came back into my mind. They simply are not technologically advanced, is it possible? So I tried a low-tech approach: phone. Of course, I couldn’t find the phone number of the service I want to reach but just a general number in Bruxelles: 02.572.57.57. After dealing with a robot for 2 minutes, I was finally put on hold for at least 20 minutes. After that, without a warning, they hanged up. I phoned again and I met their robot one more time, I waited at least 20 more minutes and they hanged up. A third try? Same results. Now, I’m fed up. They can go to hell, there are no means to contact them!

P.S. I was in the lab so don’t tell me I just have to look at my papers. Anyway, since I already sent my tax papers, I don’t have the contact address anymore.