Enzymes at work

Yale scientists have captured views of an enzyme’s working parts that show the operation of its chemical mechanisms.

“We caught the intron in action,” said principal investigator Anna Pyle, Ph.D., the William Edward Gilbert Professor of Molecular, Cellular, and Developmental Biology and professor of chemistry. Pyle’s lab reported in the October 26 issue of the journal Cell on 14 crystal structures that appear at different stages of catalysis in a group II intron—a ribozyme involved in RNA splicing.

One of RNA’s major functions is to copy genetic information so that ribosomes, the cellular protein factories, can decode it. An early step in that process is splicing—breaking RNA apart and recombining its pieces to produce a protein.

“Whenever splicing gets messed up, you’ll find a disease that results,” said Pyle, a Howard Hughes Medical Institute investigator. “Until now we haven’t really understood the splicing reaction chemically.”