Intron / Exon Structure of a eukaryotic gene

    The original discovery of the Intron / Exon structure of eukaryotic genes was made from the experiment above.

The RNA transcript of the DNA encoding chicken ovalbumin protein was hybridized back to the ssDNA template strand from which it was transcribed. Instead of a one-to-one co-linear pairing as expected based on prokaryotic DNA, the ssDNA "loops out" in order to pair with the mRNA. This indicates that the structure of the gene is a series of exons (1 - 7, above) that are expressed in the mRNA, separated by a series of intervening introns (A - G) that have been "spliced out" of the hnRNA. The mature mRNA is 1,872bp long: introns make up >75% of the length of the gene region.

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Figure © 2000 by Griffiths et al. ; text © 2024 by Steven M. Carr

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