Thursday 12 June 2008

RNA

‘RNA was the Word. RNA left behind five little clues to its priority over both protein and DNA. Even today, the ingredients of DNA are made by modifying the indredients of RNA, not by a more direct route. Also DNA’s letter Ts are made from RNA’s letter Us. Many modern enzymes, though made of protein, rely on small molecules of RNA to make them work. Moreover, RNA, unlike DNA and protein, can copy itself without assistance: give it the right ingredients and it will stitch them together into a message. Wherever you look in the cell, the most primitive and basic functions require the presence of RNA. It is an RNA-dependent enzyme that takes the message, made of RNA, from the gene. It is an RNA-containg machine, the ribosome, that translates that message, and it is a little RNA molecule that fetches and carries the amino acids for the translation of the gene’s message. But above all, RNA - unlike DNA - can act as a catalyst, breaking up and joining other molecules including RNAs themselves. It can cut them up, join the ends together, make some of its own building blocks, and elongate a chain of RNA. It can even operate on itself, cutting out a chunck of text and splicing the free ends together again. The discovery of these remarkable properties of RNA in the early 1980s… transformed our understanding of the origin of life. It now seems probable that the very first gene, the ‘ur-gene’, was a combined replicator-catalyst, a word that consumed the chemicals around it to duplicate itself. It may well have been made of RNA.’ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000

‘During the dearth and lack of those two thousand/ million years of death, one wishes primarily/ Just to grasp tightly, to compose, to circle,/ To link and fasten skilfully, as one/ Crusty grey bryozoan builds upon another,/ To be anything particular…To become godlike with transformation.’ Pattian Rogers, The Voice of the Precambrian Sea

‘Henceforth, for the animate, to last was to mean to change,/ existing both for one’s own sake, and that of all others,/ forever in jeopardy.’ WH Auden, 1907-1973, Unpredictable but Providential

‘The DNA makes a simpler molecule called RNA which interacts with ribosomes which churn out proteins based on the code in the genome. Some proteins then interact with a structure called the Golgi complex, which inspects packages and labels proteins before handing them over for distribution elsewhere in the cell.’ BBC, 2003

‘It is the classic case of chicken and egg: which came first, DNA or protein? It cannot have been DNA, because DNA is a helpless passive piece of mathematics, which catalyses no chemical reactions. It cannot have been protein, because protein is pure chemistry with no known way of copying itself accurately. It seems impossible either that DNA invented protein or vice versa. This might have remained a baffling and strange condundrum had not the word left a trace of itself faintly drawn on the filament of life. Just as we know now that eggs came long before chickens (the reptilian ancestors of all birds laid eggs), so there is growing evidence that RNA came before proteins. RNA is a chemical substance that links the two worlds of DNA and protein. It is used mainly in the translation of the message from the alphabet of DNA to the alphabet of proteins. But in the way it behaves, it leaves little doubt that it is the ancestor of both. RNA was Greece to DNA’s Rome: Homer to her Virgil.’ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000


RNA

Chemical Word -
spirit of life incarnate

in nascent chemistry -
guddling among Elements;

such light upon the water,
which will knit beams -

muscular feel of current,
into verdant dreams -

into molecular flesh,
swarming real green.


Print of the Word -
enshrined, infinite

while Earth lives.
Still star-sailing

whispering anywhere again -
hot rocks, mountains, water;

something found
out of darkness.


Communication of the Word,
translator of idea into flesh -

organic root; earth-nub;
realisation of the Word.


Active Principle of the Word -
original messenger, Olympian

bearing creativity;
life’s viral fires.


First Art of Chemistry -
first artist of the Word;

understanding desire
to be, to make, create,

for no reason but life,
expression and being.

Breaking - stitching
swarming molecules;

feeling something possible
will come into existence -

cradling one wet cell
dreaming of the flower

when no flower will be
for three billion years.


Why are men afraid to shout
these fabulous Earth miracles,

such shining, unlikely principles -
from mud and light will come us all.


RNA - understanding molecular creativity,
organic artistry, unextinguishable by time -

composer, conductor of chemicals
dreaming in water - such journey

to the white Poles, deserts, mountains,
from her bowl, sea-womb, light-seed -

spectacular travel to wing and eye,
breathing under still water, hooking

possibility from dark atoms of nothing;
connecting with star vibrations - dust.

Learner, teacher, catalysing knowledge;-
the Word driving a fantastic chemistry.

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