Structural basis of RECQL5-induced RNA polymerase II transcription braking and subsequent reactivation.

ABSTRACT: Abnormally fast transcription elongation can lead to detrimental consequences such as transcription-replication collisions, altered alternative splicing patterns and genome instability. Therefore, elongating RNA polymerase II (Pol II) requires mechanisms to slow its progression, yet the molecular basis of transcription braking remains unclear. RECQL5 is a DNA helicase that functions as a general elongation factor by slowing down Pol II. Here we report cryo-electron microscopy structures of human RECQL5 bound to multiple transcription elongation complexes. Combined with biochemical analysis, we identify an α-helix of RECQL5 responsible for binding Pol II and slowdown of transcription elongation. We further reveal that the transcription-coupled DNA repair (TCR) complex allows Pol II to overc

SUBMITTER: Zhang L 

PROVIDER: S-EPMC12440807 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature