Finding the unexpected—how we identified a second class of introns and the U12-dependent spliceosome
- Department of Molecular Biology, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
- Corresponding author: padgetr{at}ccf.org
This extract was created in the absence of an abstract.
One of the RNA stories that was unfolding at the time the RNA journal was starting up was the discovery that there were two independent types of pre-mRNA introns in some metazoans including humans. As with many unexpected findings in science, this one was as much accidental as deliberate.
My first encounter with what has come to be called the U12-dependent or minor intron class was sometime in 1989 when it was brought into my office by a UT Southwestern colleague, Alan Duby, who had cloned and sequenced the human MATN1 gene. He showed me the splice site sequences of the last intron in this gene and asked my opinion of them. They were, indeed, very odd, having unusual terminal dinucleotides of AT and AC as well as almost no other similarities to normal splice sites. I suggested initially that this was a cloning artifact but he had a partial …
