Today's molecule is related to a previous Monday's Molecule. This time you have to name the molecule and identify the various symbols on the cartoon. Be as specific as possible.
There's a direct connection between today's molecule and a Nobel Prize. The prize was awarded for figuring out how this molecule was made. It was one of the most brilliant discoveries of the 20th century.
The first person to correctly identify the molecule (and its parts) and name the Nobel Laureate(s), wins a free lunch at the Faculty Club. Previous winners are ineligible for one month from the time they first collected the prize. There are five ineligible candidates for this week's reward. You know who you are.
Send your guess to Sandwalk (sandwalk (at) bioinfo.med.utoronto.ca) and I'll pick the first email message that correctly identifies the molecule and names the Nobel Laureate(s). Note that I'm not going to repeat Nobel Laureate(s) so you might want to check the list of previous Sandwalk postings by clicking on the link in the theme box.
Correct responses will be posted tomorrow. I may select multiple winners if several people get it right.
UPDATE: The molecule is immunoglobulin G (IgG)—same as last week. The V, D, and J symbols stand for variable, diversity, and joining regions of the protein. The antigen binding site is formed from the combination of these regions on the heavy (H) chain and the light (L) chain of the molecule. The ability of antibodies to recognize a huge number of different antigens is due to formation of a huge number of different antigen-binding sites. This is achieved by rearranging the genome in order to bring together one of hundreds of V regions with 20 or so D regions and 5-6 J regions. The recombination events are associated with mutations that serve to create even more diversity.
The generation of antibody diversity by genomic rearrangement was discovered by Susumu Tonegawa who received the Nobel PRize in 1987. Today's winner is Alex Ling or the University of Toronto.