And nowhere is AS more widespread than in the brain.
"We wanted to see if AS could drive morphological differences in the brains of different vertebrate species," says Serge Gueroussov, a graduate student in Blencowe's lab who is the lead author of the study. Gueroussov previously helped identify PTBP1 as a protein that takes on another form in mammals, in addition to the one common to all vertebrates. The second form of mammalian PTBP1 is shorter because a small fragment is omitted during AS and does not make it into the final protein shape.
Could this newly acquired, mammalian version of PTBP1 give clues to how our brains evolved?