In searching for extraterrestrial life, it might be useful to broaden our vision to include the amazing mechanisms that drive animal life at all levels. We have talked about methyl groups that load onto DNA as a result of childhood abuse. Normally, methyl groups are switches that
turn a gene on or off depending on its environment. But too many can be bad news, when they accumulate on DNA in response to abuse; they can last for at least two generations.
Clues to cellular ageing, hence exo-cellular potential, include breakdown of the blood-brain barrier, shortening of telomeres, mitochondrial damage and now—surprisingly—a brain protein that lasts a lifetime, controlling messages and helping cells in the brain organize.
Earlier we learned about mini-RNA and its role in genetic regulation and disease processes. It looks like an excellent candidate for starting life, but it has been very difficult to create self-replicating RNA from scratch. The puzzle remains “How did life’s myriad parts come together?”
asks reporter Emily Singer. At least, life probably requires “a way to store information and replicate.”
Two differing approaches are being taken. Nick Hud at Georgia Tech is focusing on chemical interactions as a possible starting point for life. Biological processes probably came later. He suggests that the ribosome, found in all Earth’s living things, “…emerged from chemistry alone.” A
large diversity of chemicals could have collected, interacted and found a way to put found energy to creative use.
Maybe short strands of RNA could form and interact to create longer strands. Variations in the environment, like heating and cooling, could stir up activity, even simple metabolic reactions. But to produce more and longer strands of RNA, true copies of itself without biological tools like enzymes, seems to be very difficult. So far it has not been done in the lab.
Time may be the missing ingredient, time for the right ingredients to form and find each other, perhaps in the protected envelope of a protocell-like structure within a life-enhancing environment.
Author of The Archives of Varok
The View Beyond Earth (Book 1. Rewrite of A Place Beyond Man 1975)
The Webs of Varok (Book 2.)
Nautilus silver award 2013 YA
ForeWord finalist 2012 adult SF
The Alien Effect (Book 3.)
An Alien’s Quest–Reconciliation and Hope (Book 4. coming in 2016)
Excerpts, Synopses, Reviews, On Writing, Characters and More-
Other Book Reviews- http://www.goodreads.com/Cary_Neeper
How the Hen House Turns- http://www.ladailypost.com
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Astrobiology- http://astronaut.wpengine.com search:Who’s Out There