Summary: | 碩士 === 國立彰化師範大學 === 生物學系 === 99 === Abstract
The objective of this study was to investigate the effects of six
different polycyclic aromatic hydrocarbons (PAHs) containing two to five
aromatic rings on fruit fly, Drosophila melanogaster, using glutathione
S-transferase D3 (gstD3) mRNA expression as a biomarker. GstD3 gene,
a member of gst delta gene family, was once considered as a pseudogene
for its absence of conservative protein sequences. Recently, efforts have
been made to elucidate that gstD3 may be a functional gene and can be
induced by certain substances. Fruit flies were exposed to different PAHs
with different concentrations for 2-12 or 2-24 hours. Survived flies were
collected for RNA purification and cDNA synthesis. The expression of
gstD3 was determined by semi-quantitative RT-PCR. The results
indicated that DmgstD3 could be induced during the exposure period of
all six PAHs used, confirming that this gene was not a pseudogene.
GstD3 revealed an early-peak expression pattern (2-6hr after exposure)
when exposed to PAHs with two to four benzene rings. Moreover, all six
PAHs tested could induce the expression of gstD3 right after two hours of
exposure. This study suggests that gstD3 can be a sensitive biomarker
suitable for exposure assessments of PAHs with two to five aromatic
rings.
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