Calponin gene expression in Chironomus riparius exposed to di(2-ethylhexyl) phthalate.
Di(2-ethylhexyl) phthalate, which is a ubiquitous environmental contaminant because of its extensive use as a plasticizer, is a potential nongenotoxic carcinogen. To assess the effects of DEHP exposure on the cytoskeleton of Chironomus, we characterized full-length cDNA sequences of the calponin gene from Chironomus riparius. The expression of the calponin gene was analyzed during different life-history stages and under various DEHP concentrations for short and long periods. A phylogenetic investigation was then conducted to compare different orders of insects using sequence database analysis. The complete cDNA sequence of the calponin gene was found to be 555 bp in length. The results of phylogenetic analysis revealed that C. riparius calponin is most closely related to that of beetles. The basal level of calponin mRNA was highly expressed during different life-history stages. In addition, calponin gene expression decreased within 1 h of short-term exposure to DEHP, regardless of the concentration. We also investigated expression of the calponin gene following long-term exposure (10 days). Calponin gene expression was found to decrease significantly in C. riparius that were exposed to a low dose of DEHP, and this response was found to occur in a dose-dependent manner. Taken together, these results suggest that DEHP affects the functions of Ca(2+) binding muscle proteins such as calponin in Chironomus species.
Park
Kiyun
K
Department of Life Sciences, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejon 305-701, Republic of Korea.
Kwak
Inn-Sil
IS
D000818:Animals; D002135:Calcium-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D002683:Chironomidae / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D003599:Cytoskeleton / Q000187:drug effects; D004051:Diethylhexyl Phthalate / Q000633:toxicity*; D004785:Environmental Pollutants / Q000633:toxicity; D015870:Gene Expression / Q000187:drug effects*; D008018:Life Cycle Stages / Q000187:drug effects; D008840:Microfilament Proteins / Q000235:genetics* / Q000378:metabolism; D009124:Muscle Proteins / Q000187:drug effects; D010802:Phylogeny; D010968:Plasticizers / Q000633:toxicity*; D012333:RNA, Messenger / Q000378:metabolism; D018675:Toxicity Tests; D000096985:Calponins
D002135:Calcium-Binding Proteins; D004051:Diethylhexyl Phthalate; D004785:Environmental Pollutants; D008840:Microfilament Proteins; D009124:Muscle Proteins; D010968:Plasticizers; D012333:RNA, Messenger; D000096985:Calponins