Notes from video above:
Thioester world hypothesis (+)-> RNA world hypothesis
Amino acids and RNA spontaneously join together in conditions of water w/ neutral PH.
Thioesters provide energy for amino acids to activate and bind to RNA. They also demonstrated various specific Amino Acid diols that reacted with specific RNA diols rather than creating indiscriminate reactions with other molecules. And its the "selectivity" that's vital, preventing random non-peptide chains from forming. This creates a guided selection that would lead to specific molecules and very specific RNA chains suggesting that RNA molecules could now effectively control protein synthesis. This process does not require any enzymes and consists of a simple chemical switch with simple thioesters providing the requisite energy.
Other studies demonstrate that RNA needs a container onto which to bind itself in order to protect itself from its' environment. It forms a protocell. And here we have the "droplet world" hypothesis... that the RNA cells formed inside of a water droplet, that allowed the RNA molecules to do all their amino-acid thioester binding on the inside of the droplet. Peptides spontaneously formed very tiny soft spherical structures that scientist called coacervate droplets through the process known as liquid-liquid phase separation (LLPS). The droplets were able to undergo a steady growth division cycle by periodically adding additional monomers and essentially "growing", which would, if subjected to stress from the outside, would shear, dividing into smaller droplets that would then grow again (mimicking reproduction) with every division only taking a few hours (auto-catalytic self-reproduction). These molecules could then combine with early RNA molecules and various lipids. And when RNA would enter these droplets, they would tend to localize near the inner boundary, which helped protect the droplet from being dissolved by various lipids.
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