Group items tagged

Origins of Life Abiogenesis article in Wikipedia. The Origin of Life - Abiogenesis, a youtube video produced by Chuck Kopec.  A Simpler Origin for Life, an article by Robert Shapiro in Scientific American. The Miller-Urey Experiment article in Wikipedia. RNA and the RNA World Exploring the New RNA World, an essay by Thomas Cech published on the Nobel Prize website. RNA Video Clips from the HHMI website that include demonstrations of catalysis and interviews with Thomas Cech. A World Apart, an HHMI article about RNA World reseearch and the role of RNAs in medicine.  RNA World article in Wikipedia. Protocells The Emergence of Cells During the Origin of Life, an essay by Irene Chen published in Science.  What Came Before DNA? an article published in Discover featuring Jack Szostak and Steven Benner.  The Szostak Lab Astrobiology The National Astrobiology Institute, established by NASA to study life in the universe.  The SETI Institute, studying the origins, nature and prevalence of life in the universe.  Astrobiology: The Search for Life, a website hosted by the Exploratorium.

Because the gene-enzyme system forms a closed loop, it presents us with a classic chicken or egg conundrum: Which came first, genes or the protein enzymes they code for? While the details are still not fully worked out, discoveries over the past few decades have lead researchers to a surprising possible solution: What really came first? Genes that act as enzymes! The RNA World Hypothesis is the idea that before living cells, the genetic code, and the gene/protein cycle ever existed, chains of a chemical called RNA were forming naturally. Once formed, some of these chains were able to function as enzymes, and were even able to evolve by making copies of themselves with slight, accidental modifications.

The possibilities of pseudo-peptide-DNA mimics like PNA (peptide nucleic acid) having a role for the prebiotic origin of life prior to an RNA world is discussed on the basis of literature data showing that this type of molecules might have formed on the primitive earth (or other places in the universe), as well as data indicating the possibilities of template-directed PNA chemical replication and ligation. In particular, the merits of an achiral prebiotic genetic material is discussed.