Genetic Engineering

The landscape artists Eileen Clark has painted this image of Rydal Water, evoking Tennyson’s home of coot and heron.

I come from haunts of coot and hern,
I make a sudden sally
And sparkle out among the fern,
To bicker down a valley.

Haunts_of_Coot_and_Hern_Rydal_Watersatcrop.sized  (“Haunts of Coot & Hern” eileenclark.co.uk)

Tennyson’s fern is not the only plant in shady wet places. Another is the moss-like hornwort or Anthoceros. They can grow in the shadiest places because they have a very sensitive photo-receptor system involving a protein called neochrome, controlled by a single gene.

240px-Anthoceros_agrestis_060910c             Phaeoceros_laevis

Anthoceros  (left)                                                                      Phaeoceros – hornwort

Neochrome has been known in ferns for some time. It allows them, also, to flourish under the shady canopy of angiosperm-dominated ecosystems. It is similar to phytochrome, a better-known but less sensitive protein photoreceptor:

220px-3G6O.pdb

 

This week, an on-line paper in Proc. Nat. Ac. Ad. Sci. by Fay-Wei Lia et al shows the same neochrome gene in hornworts and ferns.

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It means plant-to-plant gene transfer took place when ferns diversified during the Cretaceous, well in time for the angiosperm radiations 60 million years ago.

This is what we call Genetic Engineering, moving genes from one species to another.

Nature turns out to be its own genetic engineer. How many times did genes move from one species of plant to another millions of years ago?

The search is on for other early plants with the neochrome gene. One candidate may be an extinct plant called Horneophyton which lived 400 million years ago. It’s found in chunks of Rhynie chert from Scotland.

 

200px-Horneophyton.svg     220px-Rhynie_chert_with_Horneophyton_1 scale 1cm

Here’s another question raised by the latest work. Could Genetic Engineering have played some part in the mysterious origin of the angiosperms?

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After all, Alfred Lord Tennyson did admit:

I steal by lawns and grassy plots,
I slide by hazel covers;
I move the sweet forget-me-nots
That grow for happy lovers.