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Alternative transcription cycle for bacterial RNA polymerase

RNA polymerases (RNAPs) transcribe genes through a cycle of recruitment to promoter DNA, initiation, elongation, and termination. After termination, RNAP is thought to initiate the next round of transcription by detaching from DNA and rebinding a new promoter. Here we use single-molecule fluorescenc...

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Detalles Bibliográficos
Autores principales: Harden, Timothy T., Herlambang, Karina S., Chamberlain, Mathew, Lalanne, Jean-Benoît, Wells, Christopher D., Li, Gene-Wei, Landick, Robert, Hochschild, Ann, Kondev, Jane, Gelles, Jeff
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6978322/
https://www.ncbi.nlm.nih.gov/pubmed/31974358
http://dx.doi.org/10.1038/s41467-019-14208-9
Descripción
Sumario:RNA polymerases (RNAPs) transcribe genes through a cycle of recruitment to promoter DNA, initiation, elongation, and termination. After termination, RNAP is thought to initiate the next round of transcription by detaching from DNA and rebinding a new promoter. Here we use single-molecule fluorescence microscopy to observe individual RNAP molecules after transcript release at a terminator. Following termination, RNAP almost always remains bound to DNA and sometimes exhibits one-dimensional sliding over thousands of basepairs. Unexpectedly, the DNA-bound RNAP often restarts transcription, usually in reverse direction, thus producing an antisense transcript. Furthermore, we report evidence of this secondary initiation in live cells, using genome-wide RNA sequencing. These findings reveal an alternative transcription cycle that allows RNAP to reinitiate without dissociating from DNA, which is likely to have important implications for gene regulation.