Genome response of model invertebrates and vertebrates species to stress agents in the environment

Abstract

The genome response of model invertebrate and vertebrate species to stress agent in the environment was studied. The both group of species were collected from contaminated water stations along Marisa (Kemera) and Chaya (Asenovgrad) Rivers and terrestrial areas near Asenovgrad. The structural and functional alterations of the salivary gland chromosomes of Chironomus riparius as well as the aberrations of mitotic chromosomes of Apodemus flavicollis and Microtus arvalis were analyzed. In the polytene chromosomes of C. riparius a high spectrum of somatic aberrations were detected, which appeared in significantly higher frequency in comparison of the control (Kemera: G=37.99, df=1, P<0.001; Asenovgrad, G = 42.82, df = 1, P<0.001). Also, the key structure of the polytene chromosomes: Balbiani rings and Nucleolar Organizer decreased their normal function activity which indicates that they are direct target for the stress of contaminants in the environment. The frequency of aberrant cells of small rodents (Apodemus flavicollis and Microtus arvalis) was significantly higher than the control, well expressed in M. arvalis (G = 4.54, df =1, P <0.05). In both groups of studied species genome instability were found, realized by many structure chromosome rearrangements which can be used as a cost-effective indicator of genotoxicity, and hence suitable markers of potential environmental stress. However, the studied species show differences in their response which might be depended on their biology. © 2010 Taylor and Francis Group, LLC.