Heat-shock protein (Hsp70) and cytochrome P-450 (CYP1A) in the white mulletMugil curema(Pisces:Mugilidae) as biomarkers to assess environmental quality in coastal lagoons

Abstract

Biomarkers have been useful tools to monitor some effects of pollution in coastal environments. Hepatic expression of heat-shock protein 70 (Hsp70) and cytochrome P450 1A (CYP1A) were analyzed in white mullet (Mugil curema) by RT-PCR from July, 2005 until July, 2006 in three coastal lagoons located in the southern Gulf of California, Mexico. These three coastal systems receive contaminants derived from local anthropogenic activities. Heat-shock proteins function to maintain protein integrity in the presence of stressors (such as heat or chemicals) and can be used as biomarkers of homeostatic alterations in polluted environments, whereas cytochrome P450 family members participate in steroid hormone synthesis and metabolism, and in xenobiotic transformation as a detoxification mechanism. The expression levels of both genes showed consistency in time and space, and presented a high overall correlation (r = 0.731, P < 0.001). Regardless of a high individual variability, both genes presented higher expression levels in the Urias Estuary (P < 0.001 and P < 0.05 for CYP1A and Hsp70, respectively), which was considered the most polluted among the three systems, especially during the rainy season (summer to fall). Gene expression levels were significantly associated with non-halogenated hydrocarbon concentrations in sediments during the sampling period (r = 0.686, P = 0.019 for CYP1A and r = 0.91, P < 0.001 for Hsp70), suggesting that both genes respond to chemicals in the environment. The results indicate that Mugil curema is a good candidate species to implement biomonitoring programs in tropical coastal environments.

Identification of a warm‐temperature acclimation‐associated 65‐kDa protein encoded by a temperature‐ and infection‐responsive gene in the Kumgang fat minnow Rhynchocypris kumgangensis

“…Elevated water temperature generally leads to an increase in expression levels of hsp genes in several fish (Arai et al, ; Ojima et al, ; Cui et al, ; Im and Ghil, ). Hsps also respond to various environmental stresses, such as heavy metals, pollution, and infection (Rios‐Sicairos et al, ; Roberts et al, ; Lapointe et al, ; Ribecco et al, ).…”

Regulation of cytochrome P4501A by protein kinase C: the role of heat shock protein70

“…As mentioned before, HSP70 is a molecular chaperon that helps in maintaining conformity of many cellular proteins (Hartl and Martin 1995; Martin and Hartl 1997). In fact the expression of HSP70 remained high throughout the year in livers of fishes that live in water polluted with hydrocarbon (Rios‐Sicairos et al). This observation indicated that HSP70 was required for maintaining conformity of cytochrome P450 protein including EROD that might be required for detoxification of pollutants.…”

“…In the present study, we investigated to test whether there is any relationship between the expression of heat shock protein70 (HSP70) and carbofuran‐ induced CYP1A1 because only few reports have indicated that HSP70 could be involved in the regulation of EROD (Ferraris et al 2002; Rajagopalan et al 2005; Rios‐Sicairos et al 2010). In our study, it has been observed that induction of CYP1A1 is associated with the increase of PKC and HSP70 and both have parallel dose dependent function with CF.…”