Gueroussov showed that in mammalian cells, the presence of the shorter version of PTBP1 unleashes a cascade of AS events, tipping the scales of protein balance so that a cell becomes a neuron.
What’s more, when Gueroussov engineered chicken cells to make the shorter, mammalian-like PTBP1, this triggered AS events that are found in mammals.
“One interesting implication of our work is that this particular switch between the two versions of PTBP1 could have affected the timing of when neurons are made in the embryo in a way that creates differences in morphological complexity and brain size,” says Blencowe, who is also Banbury Chair in Medical Research and a professor in the department of molecular genetics.