Title: Detection method for irradiated Oriental fruit fly (Bactrocera philippinensis) for quarantine purposes Authors: Teresa Yulo-Nazarea, Alejandro Q. Nato, Jr., and Javier M. Eduardo Technical Report Institution: Philippine Nuclear Research Institute Catalogued by: International Nuclear Information System Publication Date: 1995 Volume: 28 Issue: 13 Technical Report Source:PNRI-F(PR)--97001 Technical Report Reference Number:28043698 Abstract: The presence of a biochemical marker for irreversible radiation injury in an insect pest was identified in pupae of irradiated larvae of Bactrocera philippinensis. A radiation sensitive marker protein (designated Gs-protein) for radiation injury in the Oriental fruit fly, B. philippinensis, was detected in the SDS-PAGE profile of two-day
old pupae and adult insect stage. Gs-protein is not observed in larvae and eggs. An apparent molecular weight of 109 kDa was calculated. A tyrosinase enzyme activity was observed in the soluble fraction of pupal total homogenate and SDS-PAGE-isolated Gs-protein; however, no tyrosinase activity was measured in irradiated sample. Preliminary TXRF (total reflection x-ray fluorescence) spectrometric analysis indicates that Gs-protein is a copper-containing enzyme. The optical absorbance of the soluble fraction from unirradiated pupal total homogenate measured at 360 nm was found to increase with time. The presence of highly absorbing chromophore(s) in the visible range in both samples may indicate that a certain type of tyrosinase activity (other than melanin formation) may be present and may be responsible for color formation in insects. From the results of the studies, the apparent loss of Gs-protein in irradiated larvae is the likely result of loss of melanization capability in irradiated larvae which, in turn, is linked to the absence of a certain type of tyrosinase activity. The data presented indicates the practical role of Gs-protein as a biomarker for gamma irradiation-induced arrest of pupal development and as a convenient indicator of the efffectiveness of gamma irradiation as a quarantine treatment. Citation PDF URL:http://faculty.washington.edu/aqnato/pdf/1995_Nazarea_Nato_Technical_Report_Radiation_Injury_131-135.pdf
