Developmental genetics and symbiotic potential of cyanobacteria

Many cyanobacteria can differentiate specialized cells – heterocysts that fix nitrogen aerobically, akinetes able to survive under unfavorable conditions, and hormogonia providing a means of dispersal. Of great importance for evolution of the biosphere was the ability of cyanobacteria to establish symbioses with eukaryotic organisms that was a prerequisite for the emergence of chloroplasts. This review describes the genes and regulatory systems that control differentiation of specialized cells and the ability of cyanobacteria to establish symbiotic associations with a variety of hosts.