Researchers from AIST, in collaboration with the University of Montana (USA), the Open University of Japan, and others, have discovered that two types of bacteria with extremely reduced genomes endocellularly reside in a nested manner within the symbiotic organ of mealybugs that are known as agricultural pests, and that more than 20 different genes laterally transferred from various bacteria to the insect's genome in the past are expressed in the symbiotic organ. The researchers also found that these symbiont genomes and laterally transferred bacterial genes together form mutually complementary metabolic pathways essential for the symbiotic relationship in a mosaic manner, which are involved in synthesis of amino acids, vitamins, and cell walls. Such a complexity of the symbiotic system is beyond what has been conventionally believed.
↧