How an enzyme complex gets around chromosomal barriers
© JUAN GAERTNER/SCIENCE PHOTO LIBRARY/Getty
An enzyme that converts DNA into RNA works cooperatively with two helper proteins to coordinate movement in and around structural barriers called nucleosomes, thereby enabling the forward march of gene transcription along the chromosome.
Using cryo-electron microscopy on proteins derived from yeast, a team in Japan co-led by scientists from Waseda University snapped atomic-resolution images of RNA polymerase II in complex with elongation factors that enhance the enzyme’s activity.
The images showed that two elongation factors named Elf1 and Spt4/5 help adjust the position of the spool-like nucleosomes to facilitate progression of the polymerase enzyme at tightly wound regions of the chromosome known as superhelices.
The structural findings offer an unprecedented level of detail into how molecular machines inside each cell nucleus help decode information contained within the genome.
- Science 363, 744–747 (2019). doi: 10.1126/science.aav8912
|RIKEN Center for Biosystems Dynamics Research (BDR), Japan||0.64|
|Laboratory of Chromatin Structure and Function, UTokyo, Japan||0.22|
|Graduate School of Advanced Science and Engineering, Waseda University, Japan||0.14|