title: Biological effects of anhydrobiosis in an African chironomid, Polypedilum vanderplanki on radiation tolerance.
abstract: OBJECTIVE
  Anhydrobiotic organisms are known to have an extremely high tolerance against a range of stresses. However, the functional role of anhydrobiosis in radiation tolerance is poorly understood, especially in development following irradiation. The present study aims to evaluate effects of anhydrobiosis on radiation tolerance in an anhydrobiotic insect, Polypedilum vanderplanki.
  
  
  METHODS
  Larval survival (48 h), anhydrobiotic ability, metamorphosis and reproduction after exposure to 1-9000 Gy of gamma-rays at the larval stage were compared between anhydrobiotic (dry) and normal (wet) phases.
  
  
  RESULTS
  Wet larvae were killed in a dose-dependent manner at doses higher than 2000 Gy, and all died within 8 h after 4000 Gy exposure. In contrast, dry larvae survived even 5000 Gy, and some of them still tolerated 7000 Gy and were alive at 48 h after rehydration. Moreover, greater radiotolerance of dry larva, compared to wet ones, was demonstrated in terms of metamorphoses. However, anhydrobiosis did not protect against radiation damage in terms of producing viable offspring.
  
  
  CONCLUSIONS
  These results indicate that anhydrobiosis enhances radiotolerance, resulting in increases of successful metamorphoses.
authors.affiliation: Department of Physiology and Genetic Regulation, National Institute of Agrobiological Sciences (NIAS), Tsukuba, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Sakashita
authors.forename: Akihiko
authors.initials: A
authors.lastname: Fujita
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kikawada
authors.forename: Daiki D
authors.initials: DD
authors.lastname: Horikawa
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Nakahara
authors.forename: Seiichi
authors.initials: S
authors.lastname: Wada
authors.forename: Tomoo
authors.initials: T
authors.lastname: Funayama
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Hamada
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Okuda
mesh_terms: D000818:Animals; D001834:Body Water / Q000378:metabolism*; D004175:Diptera / Q000502:physiology* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D007814:Larva / Q000502:physiology / Q000528:radiation effects; D011829:Radiation Dosage; D011836:Radiation Tolerance / Q000502:physiology*