title: Capsule-transmitted gut symbiotic bacterium of the Japanese common plataspid stinkbug, Megacopta punctatissima.
abstract: The Japanese common plataspid stinkbug, Megacopta punctatissima, deposits small brown particles, or symbiont capsules, on the underside of the egg mass for the purpose of transmission of symbiotic bacteria to the offspring. We investigated the microbiological aspects of the bacteria contained in the capsule, such as microbial diversity, phylogenetic placement, localization in vivo, and fitness effects on the host insect. Restriction fragment length polymorphism analysis of 16S ribosomal DNA clones revealed that a single bacterial species dominates the microbiota in the capsule. The bacterium was not detected in the eggs but in the capsules, which unequivocally demonstrated that the bacterium is transmitted to the offspring of the insect orally rather than transovarially, through probing of the capsule content. Molecular phylogenetic analysis showed that the bacterium belongs to the gamma-subdivision of the Proteobacteria. In adult insects the bacterium was localized in the posterior section of the midgut. Deprivation of the bacterium from the nymphs resulted in retarded development, arrested growth, abnormal body coloration, and other symptoms, suggesting that the bacterium is essential for normal development and growth of the host insect.
authors.affiliation: Research Institute of Biological Resources, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8566, Japan. t-fukatsu@aist.go.jp
authors.forename: Takema
authors.initials: T
authors.lastname: Fukatsu
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hosokawa
mesh_terms: D000818:Animals; D004275:DNA, Ribosomal / Q000032:analysis; D004064:Digestive System / Q000382:microbiology*; D005260:Female; D020563:Gammaproteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology*; D020062:Heteroptera / Q000254:growth & development / Q000382:microbiology* / Q000648:ultrastructure; D007564:Japan; D008297:Male; D008969:Molecular Sequence Data; D010063:Ovum / Q000254:growth & development / Q000382:microbiology*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013559:Symbiosis
chemical_list: D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S