An extensive network of coupling among gene expression machines

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Gene expression in eukaryotes requires several multi-component cellular machines. Each machine carries out a separate step in the gene expression pathway, which includes transcription, several pre-messenger RNA processing steps and the export of mature mRNA to the cytoplasm. Recent studies lead to the view that, in contrast to a simple linear assembly line, a complex and extensively coupled network has evolved to coordinate the activities of the gene expression machines. The extensive coupling is consistent with a model in which the machines are tethered to each other to form ‘gene expression factories’ that maximize the efficiency and specificity of each step in gene expression.

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Figure 1: A complex network of coupled interactions in gene expression.
Figure 2: Gene expression factory model for coupling steps in gene expression.
Figure 3: Model for coupling splicing to mRNA export and nonsense-mediated decay.


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We thank R. Axel, D. Bentley, S. Buratowski, B. Graveley, J. Manley, M. Ptashne and members of our labs for their comments on the manuscript. We also thank R. Hellmiss for the illustrations.

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Correspondence to Tom Maniatis or Robin Reed.

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