Nuclear myosin I is necessary for the formation of the first phosphodiester bond during transcription initiation by RNA polymerase II

  title={Nuclear myosin I is necessary for the formation of the first phosphodiester bond during transcription initiation by RNA polymerase II},
  author={Wilma A. Hofmann and Gabriela M. Vargas and Ramaswamy Ramchandran and Ljuba Stojiljkovi{\'c} and James A. Goodrich and Primal de Lanerolle},
  journal={Journal of Cellular Biochemistry},
The nuclear isoform of myosin, Nuclear Myosin I (NMI) is involved in transcription by RNA polymerase I. Previous experiments showing that antibodies to NMI inhibit transcription by RNA polymerase II using HeLa cell nuclear extract (NE) suggested that NMI might be a general transcription factor for RNA polymerases. In this study we used a minimal in vitro transcription system to investigate the involvement of NMI in transcription by RNA polymerase II in detail. We demonstrate that NMI co… 

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Title Persistent nuclear actin filaments inhibit transcription by RNA polymerase II Permalink

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Myosin VI regulates the spatial organisation of mammalian transcription initiation

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Transcriptional control of gene expression by actin and myosin.

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Nuclear phosphatidylinositol 4,5-bisphosphate islets contribute to efficient RNA polymerase II-dependent transcription

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Nuclear actin and myosin I are required for RNA polymerase I transcription

Investigation of the role of actin and nuclear myosin I in the transcription of ribosomal RNA genes (rDNA) suggests a role for NMI in the growth-dependent regulation of rRNA synthesis.

Actin is part of pre-initiation complexes and is necessary for transcription by RNA polymerase II

A fundamental role for actin in the initiation of transcription by RNA polymerase II is suggested after it was demonstrated that antibodies directed against β-actin, but not muscle actin, inhibited transcription in vivo and in vitro.

Actin and hnRNP U cooperate for productive transcription by RNA polymerase II

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A kinetic model for the mechanism of RNA polymerase II transcription is presented that describes five distinct steps (preinitiation complex formation, initiation, escape commitment, promoter escape, and transcript elongation) and clearly shows promoter escape is rate-limiting in this system.

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An actin-myosin complex on actively transcribing genes.