protoneja

Protoneja is a term used in origin-of-life discourse to denote a hypothetical transitional entity between simple chemical assemblies and modern cellular life. The concept serves as a model to explore how primitive metabolism and genetic information could co-emerge within a compact, container-like compartment.

A protoneja would be small, membrane-bound structures containing a limited set of catalytic molecules and a short, RNA-like genetic system capable of storing information and guiding replication of both genetic material and metabolic catalysts. Metabolism in protonejas is envisioned as a minimal, autocatalytic network that generates essential building blocks, maintains compartment integrity, and allows growth and occasional division of the vesicle.

In theoretical scenarios, protonejas could arise in diverse prebiotic settings, such as mineral-rich ponds, tidal pools, or hydrothermal vent environments where organic molecules accumulate and organize within lipid vesicles or coacervates. They are often posited as precursors to protocells, offering a simpler mixed model that focuses on chemical self-organization and limited heredity.

Relation to other concepts: Protoneja is usually placed upstream of protocells in origin-of-life frameworks. It is related conceptually to coacervates, micelles, and simple lipid vesicles, but specifically emphasizes an early, self-sustaining metabolism coupled to a basic genetic system.

Criticism: Protoneja remains speculative with no direct empirical evidence. It is one of several heuristic constructs used to test ideas about the sequence of events that led to life.