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Identification of the Full 46 Cytochrome P450 (CYP) Complement and Modulation of CYP Expression in Response to Water-Accommodated Fractions of Crude Oil in the Cyclopoid Copepod Paracyclopina nana
journal contribution
posted on 2015-06-02, 00:00 authored by Jeonghoon Han, Eun-Ji Won, Hui-Su Kim, David
R. Nelson, Su-Jae Lee, Heum Gi Park, Jae-Seong LeeThe 46 cytochrome P450 (CYP) gene superfamily
was identified in the marine copepod Paracyclopina nana after searching an RNA-seq database and comparing it with other
copepod CYP gene families. To annotate the 46 Pn-CYP genes, a phylogenetic analysis of CYP genes was performed using a Bayesian method. Pn-CYP genes were separated into five different clans: CYP2, CYP3, CYP20,
CYP26, and mitochondrial. Among these, the principal Pn-CYP genes involved in detoxification were identified by comparing them
with those of the copepod Tigriopus japonicus and
were examined with respect to their responses to exposure to a water-accommodated
fraction (WAF) of crude oil and to the alkylated forms of two polycyclic
aromatic hydrocarbons (PAHs; phenanthrene and fluorene). The expression
of two Pn-CYP3027 genes (CYP3027F1 and CYP3027F2) was increased in response to WAF
exposure and also was upregulated in response to the two alkylated
PAHs. In particular, Pn-CYP3027F2 showed the most
notable increase in response to 80% WAF exposure. These two responsive CYP genes (Pn-CYP3027F1 and CYP3027F2) were also phylogenetically clustered into the same clade of the
WAF- and alkylated PAH-specific CYP genes of the
copepod T. japonicus, suggesting that these CYP genes would be those chiefly involved in detoxification
in response to WAF exposure in copepods. In this paper, we provide
information on the copepod P. nana CYP gene superfamily
and also speculate on its potential role in the detoxification of
PAHs in marine copepods. Despite the nonlethality of WAF, Pn-CYP3027F2 was rapidly and significantly upregulated in
response to WAF that may serve as a useful biomarker of 40% or higher
concentration of WAF exposure. This paper will be helpful to better
understand the molecular mechanistic events underlying the metabolism
of environmental toxicants in copepods.