Evolutionary origins of metabolic compartmentalization in eukaryotes

摘要: Many genes in eukaryotes are acquisitions from the free-living antecedents of chloroplasts and mitochondria. But there is no evolutionary ‘homing device’ that automatically directs protein product a transferred gene back to organelle its provenance. Instead, products acquired endosymbionts can explore all targeting possibilities within cell. They often replace pre-existing host genes, or even whole pathways. transfer an enzymatic pathway one compartment another poses severe problems: over time, enzymes acquire their signals for new individually, not unison. Until established compartment, newly routed individual useless, will be lost through mutation. Here it suggested pathways attain novel compartmentation variants via ‘minor mistargeting’ mechanism. If eukaryotic cells possesses enough imperfection such small amounts entire continuously enter compartments, selectable units biochemical function would exist could become selected. Dual-targeting proteins indeed very common cells, suggesting variation required this minor mistargeting mechanism operate exists nature.