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Introns and the origin of nucleus–cytosol compartmentalization


The origin of the eukaryotic nucleus marked a seminal evolutionary transition. We propose that the nuclear envelope's incipient function was to allow mRNA splicing, which is slow, to go to completion so that translation, which is fast, would occur only on mRNA with intact reading frames. The rapid, fortuitous spread of introns following the origin of mitochondria is adduced as the selective pressure that forged nucleus–cytosol compartmentalization.

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Figure 1: Origin of nucleus–cytosol compartmentalization in the wake of mitochondrial origin.


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We thank the DFG (W.M.) and the NIH intramural research program (E.V.K.) for financial support, and M. Embley, T. Dagan, I. Rogozin, T. Senkevich and Y. Wolf for discussions.

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Correspondence to William Martin.

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Martin, W., Koonin, E. Introns and the origin of nucleus–cytosol compartmentalization. Nature 440, 41–45 (2006).

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