Rappin’ pela ciência

terça-feira, março 10, 2009

How can a single fertilized egg turn into a full-fledged organism? The two rappers at Stanford University provide the answer in the above video: “Regulatin’ Genes.”


The rapper on the left is Derrick Davis, a junior at Stanford. The rapper on the right is Tom McFadden, an instructor in the human biology program there. “While the lyrics are original,” Mr. McFadden told me, “the song is actually a parody of Jay-Z’s “Money Ain’t a Thang”. In their video, they have so much money that they flip through it, throw it up in the air, throw it out of moving vehicles. Since we just had midterms, I’m projecting some wishful thinking in the video - that there are so many A+’s on the midterm that we can just throw them in the air.”

And just in case you don’t follow every nuance in the video, like the Hox reference, here’s Mr. McFadden’s non-rap summary of the biology lesson:

Since virtually all cells have the same genome, cell specialization (for example: whether a cell becomes a neuron or a skin cell) is largely controlled by which genes are actually transcribed in a given cell. This can be controlled by transcription factors - proteins which bind to DNA and interact with the cellular machinery to control gene expression. An important family of transcription factors are Hox genes, which control which body parts grow where.

Hox genes control where legs, wings, and antennae grow in the fruit fly (so mutating them leads to some strange creatures). These same Hox genes have been highly conserved during evolution, and control vertebrae specialization in mice and humans. This helps to bring home a main lesson of developmental biology: that creating different body forms isn’t so much about what genes you have, but how you regulate them.


Tirando o chapéu para John Tierney.