Cryo-EM structures reveal transcription initiation steps by yeast mitochondrial RNA polymerase

Brent De Wijngaert; Shemaila Sultana; Chhaya Dharia; Hans Vanbuel; Jiayu Shen; Daniel vasilchuk; Sergio E Martinez; Eaazhisai Kandiah; Smita S Patel; Kalyan Das

. CC-BY-NC-ND 4.0 International license author/funder. It is made available under a The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.04.13.038620 doi: bioRxiv preprint The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.04.13.038620 doi: bioRxiv preprint The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.04.13.038620 doi: bioRxiv preprint Movies S1 -S3 Movie S1. Overall structural change in the transition from PIC to IC. Morphing between the transcription pre-initiation state (y-mtPIC, gray RPO41 and DNA, yellow MTF1) and initiation state (y-mtIC, yellow MTF1, blue RPO41, cyan non-template, and pink template) simulates the conformational changes in the promoter and protein during transition from the PIC to IC state. The downstream DNA bends inward and parts of the C-terminal domain including fingers (in front) undergo large conformational changes. MTF1, upstream DNA, and parts of the N-terminal domain of RPO41 that interact with MTF1 and upstream DNA show minimal conformational changes; e.g. the thumb helix on the left and MTF1 on the top have minimal movements.