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

@article{Hofmann2006NuclearMI,
  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},
  year={2006},
  volume={99}
}
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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References

SHOWING 1-10 OF 16 REFERENCES

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

The results indicate that a general actin-based mechanism is implicated in the transcription of most Pol II genes and actin in complex with hnRNP U may carry out its regulatory role during the initial phases of transcription activation.

A Kinetic Model for the Early Steps of RNA Synthesis by Human RNA Polymerase II*

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.

The chromatin remodelling complex WSTF–SNF2h interacts with nuclear myosin 1 and has a role in RNA polymerase I transcription

It is shown by biochemical fractionation of nuclear extracts, protein–protein interaction studies and chromatin immunoprecipitation assays that NM1 is part of a multiprotein complex that contains WICH, a chromatin remodelling complex containing WSTF and SNF2h.

Nuclear distribution of actin and myosin I depends on transcriptional activity of the cell

It is demonstrated that actin and NMI are compartmentalized in the nuclei where they can dynamically translocate depending on transcriptional activity of the cells.

Factors involved in specific transcription by mammalian RNA polymerase II: purification and characterization of general transcription factor TFIIE.

Results suggested that TFIIE is a heterotetramer containing two alpha and two beta polypeptides, and that it is a general initiation factor, required for all of the genes tested, but it failed to show any DNA-dependent ATPase activity.

An actin-myosin complex on actively transcribing genes.