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bioRxiv · 10.1101/2025.03.21.644610

Structure of a transcribing Pol II-DSIF-SPT6-U1 snRNP complex

Zhang, L.·Batters, C.·Aibara, S.·Gordiyenko, Y.·Zumer, K.·Maier, K.·Cramer, P.·Zhang, S.
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Abstract

RNA polymerase II (Pol II) facilitates co-transcriptional splicing by recruiting the U1 small nuclear ribonucleoprotein particle (U1 snRNP) to the nascent transcripts. Here, we report the cryo-electron microscopy structure of a transcribing Pol II-U1 snRNP complex with elongation factors DSIF and SPT6. Furthermore, our biochemical analysis revealed that the phosphorylated Pol II carboxyl-terminal domain and SPT6 interact directly with U1 snRNP proteins, facilitating its recruitment to the elongation complex. This multivalent interaction allows efficient spliceosome assembly and ensures transcription processivity.

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Zhang, L., Batters, C., Aibara, S., Gordiyenko, Y., Zumer, K., Maier, K., Cramer, P., Zhang, S.. 2025-03-21. Structure of a transcribing Pol II-DSIF-SPT6-U1 snRNP complex. https://doi.org/10.1101/2025.03.21.644610

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