Thermotolerance and HSP70 expression in the Mediterranean fruit fly  Ceratitis capitata.
The relationship between Hsp70 expression and thermotolerance has been well documented in Drosophila melanogaster. However, there is limited information on this relationship in other insect species. In this report we describe the Hsp70-thermotolerance relationship in one of the major fruit fly pests, Ceratitis capitata (medfly). Hsp70 expression and thermotolerance were assayed at a range of temperatures in several stages of medfly development. The most thermotolerant stage was found to be the late larval stage (100% survival at 41 degrees C) followed by adult flies and late embryos (100% survival at 39 degrees C). These three stages showed a positive relationship between Hsp70 expression and thermotolerance. Mid-larval and mid-embryonic stages were found less thermotolerant and the Hsp70-thermotolerance relationship was not evident. Early embryos did not express Hsp70 at any temperature and exhibited the lowest thermotolerance. The relationship between Hsp70 and inducible thermotolerance was also studied in late larvae. A pretreatment at 37-39 degrees C increased thermotolerance at higher temperatures by approximately 1 degrees C. In parallel, the pretreatment increased Hsp70 expression suggesting a close link between Hsp70 expression and inducible thermotolerance. The increased Hsp70 levels after pretreatment were found to be due to the increased levels of the hsp70 RNA.
Kalosaka
Katerina
K
Division of Genetics, Cell and Developmental Biology, Department of Biology, University of Patras, Patras, Greece.
Soumaka
Elisavet
E
Politis
Nikos
N
Mintzas
Anastassios C
AC
D000818:Animals; D033622:Ceratitis capitata / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D015870:Gene Expression; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D006358:Hot Temperature; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000502:physiology
D018840:HSP70 Heat-Shock Proteins; D019476:Insect Proteins