Annual Reviews Extra | RNA Splicing by the Spliceosome: Supplemental Video 4 @annualreviewsextra | Uploaded December 2019 | Updated October 2024, 2 hours ago.
A supplemental video from the 2020 review by Max E. Wilkinson, Clément Charenton, and Kiyoshi Nagai, "RNA Splicing by the Spliceosome," from the Annual Review of Biochemistry: annualreviews.org/doi/10.1146/annurev-biochem-091719-064225?utm_source=youtube&utm_medium=bi.wilkinson&utm_campaign=suppvideo
Shown: Spliceosome activation, showing transition from B complex to Bact complex and formation of the active site. Structures derive from PDB codes 6AHD for human B complex (79) and 5Z56 for human Bact complex (94a), with other structures informing the transition (148, 94b). U4/U6 di-snRNP proteins are shown departing before Brr2 action on the U4/U6 duplex but these events may coincide. Transcription of narration: “This is human B complex. The 5′SS is properly positioned while the branch point adenosine is distant and the active site is not formed. At some unknown time, the B-complex proteins and other factors dissociate. This probably coincides with the activity of the Brr2 helicase, which unwinds the U4/U6 duplex. In the absence of its U4 chaperone, U6 can fold into the active site together with U2. The newly formed active site holds two catalytic magnesium ions close to the 5′SS. However, the branching reaction cannot occur because Cwc24 shields the 5′SS, and SF3b encapsulates the branch point. This new conformation of the spliceosome is stabilized by the NTC and NTR complexes, forming Bact complex.” Video used with permission from the MRC Laboratory of Molecular Biology, Cambridge, UK.
A supplemental video from the 2020 review by Max E. Wilkinson, Clément Charenton, and Kiyoshi Nagai, "RNA Splicing by the Spliceosome," from the Annual Review of Biochemistry: annualreviews.org/doi/10.1146/annurev-biochem-091719-064225?utm_source=youtube&utm_medium=bi.wilkinson&utm_campaign=suppvideo
Shown: Spliceosome activation, showing transition from B complex to Bact complex and formation of the active site. Structures derive from PDB codes 6AHD for human B complex (79) and 5Z56 for human Bact complex (94a), with other structures informing the transition (148, 94b). U4/U6 di-snRNP proteins are shown departing before Brr2 action on the U4/U6 duplex but these events may coincide. Transcription of narration: “This is human B complex. The 5′SS is properly positioned while the branch point adenosine is distant and the active site is not formed. At some unknown time, the B-complex proteins and other factors dissociate. This probably coincides with the activity of the Brr2 helicase, which unwinds the U4/U6 duplex. In the absence of its U4 chaperone, U6 can fold into the active site together with U2. The newly formed active site holds two catalytic magnesium ions close to the 5′SS. However, the branching reaction cannot occur because Cwc24 shields the 5′SS, and SF3b encapsulates the branch point. This new conformation of the spliceosome is stabilized by the NTC and NTR complexes, forming Bact complex.” Video used with permission from the MRC Laboratory of Molecular Biology, Cambridge, UK.
